TECHNICAL PROGRAMME | Primary Energy Supply – Future Pathways
The Role of Biofuels as a Feedstock
Forum 6 | Digital Poster Plaza 1
30
April
12:00
14:00
UTC+3
This session delves into the innovative use of biofuels as a feedstock in various industries, emphasising their potential to contribute to sustainable production processes. The session will explore the latest advancements in biofuel technologies, feedstock optimisation, and the role of biofuels in reducing greenhouse gas emissions, with insights into the scientific principles, engineering challenges, and economic considerations involved in the utilisation of biofuels as a versatile feedstock.
After a decade-long tardy progress, the Ethanol Blending program in India started on a progressive pathway, and there has been consistent improvement in ethanol-fuel blending ratios since then, primarily due to diversification in first-generation ethanol feedstocks. India now aims to achieve a 30% ethanol fuel blending ratio in the coming years, which requires stringent planning and policy support to meet the rising demand for ethanol. With emphasis on second-generation (2G) ethanol production (from non-edible feedstocks), the Government launched a financial support scheme, Pradhan Mantri JI-VAN (Jaiv Indhan- Vatavaran Anukool fasal awashesh Nivaran) Yojana, to the tune of 230 million USD for setting up twelve integrated 2G Bio-ethanol Projects for the period 2018-19 to 2023-24. However, the issue of higher production cost of 2G ethanol makes it difficult for the oil marketing companies (OMCs) to absorb the additional cost and makes it economically unviable for adoption. This paper examines the role of techniques in production processes as well as the development of carbon markets in the production of 2G ethanol that can make it viable for long-term adoption.
Through forecasting techniques, we calculate the future ethanol requirement vis-à-vis gasoline demand while taking into account the impact of energy transition through other alternative energy sources. We then assess the environmental and economic impacts of 2G ethanol with the help of simulation, scenario, and sensitivity analysis. We then re-evaluate and compare the economic impact, taking into account carbon credits that can be generated through the adoption of 2G ethanol.
Results indicate that the cost of 2G ethanol production decreases with time. This cost decreases significantly in the case of setting up an integrated bio-refinery in place of a standalone biorefinery. However, this decrease is not enough to compensate or compete with the 1G (first generation) ethanol or petrol prices. However, while taking into consideration the social cost of carbon, the second-generation ethanol becomes economically viable when carbon credit accounting is incorporated in the economic analysis. The results are also helpful in suggesting policy measures that can aid in the long-term successful adoption of 2G ethanol.
The paper indicates the growing importance of carbon markets, which are all set to launch in India in 2026. The techno-economic analysis provides insights with regard to the impact of the process adopted for 2G ethanol production on its long-term adoption and viability. The paper also successfully highlights the importance of ethanol fuel in helping to achieve decarbonisation and strengthen energy security. Further, the ambitious targets of switching to an ethanol economy cannot be achieved alone by 1G ethanol.
Through forecasting techniques, we calculate the future ethanol requirement vis-à-vis gasoline demand while taking into account the impact of energy transition through other alternative energy sources. We then assess the environmental and economic impacts of 2G ethanol with the help of simulation, scenario, and sensitivity analysis. We then re-evaluate and compare the economic impact, taking into account carbon credits that can be generated through the adoption of 2G ethanol.
Results indicate that the cost of 2G ethanol production decreases with time. This cost decreases significantly in the case of setting up an integrated bio-refinery in place of a standalone biorefinery. However, this decrease is not enough to compensate or compete with the 1G (first generation) ethanol or petrol prices. However, while taking into consideration the social cost of carbon, the second-generation ethanol becomes economically viable when carbon credit accounting is incorporated in the economic analysis. The results are also helpful in suggesting policy measures that can aid in the long-term successful adoption of 2G ethanol.
The paper indicates the growing importance of carbon markets, which are all set to launch in India in 2026. The techno-economic analysis provides insights with regard to the impact of the process adopted for 2G ethanol production on its long-term adoption and viability. The paper also successfully highlights the importance of ethanol fuel in helping to achieve decarbonisation and strengthen energy security. Further, the ambitious targets of switching to an ethanol economy cannot be achieved alone by 1G ethanol.
Objective:
India is an agrarian economy with immense potential og agro-waste for sustainable energy production. Tapping this potential will make India Self-sustained in terms of Energy demand and will contribute towards Socio-economic & Environmental Development. However, efficient & effective management of agro-waste poses many challenges w.r.t Seasonal Availability, Storage, logistics challenges, Huge capex requirement for purchasing farm Machniaries, opex cost of biomass depot & lack of Govt Policies in place.
Roles of stakeholders and challenges associated:
There are 3 stakeholders associated with agro-waste supply chain as follows:
Farmers/aggregators contribute towards aggregation of agro-waste from fields and further transportation of it to the owners.
Challenges with farmers:
Challenges with aggregators:
Plant Owners play crucial role in setting-up commercially viable plants.
Challenges associated with owners:
District Administartion plays a crucial role in liasioning between farmer and owners & formulating suitable policies for successful execution.
Potential solution:
Although biofuel business is having many challenges associated, they can still ensure a healthy environment, reduce import dependency on fossil fuels, employment generation and additional income for farmers through crop incentivisations. The Government of India must look into the sustainable production of biofuels with feasible, clear policy and financial support to make India a global champion.
India is an agrarian economy with immense potential og agro-waste for sustainable energy production. Tapping this potential will make India Self-sustained in terms of Energy demand and will contribute towards Socio-economic & Environmental Development. However, efficient & effective management of agro-waste poses many challenges w.r.t Seasonal Availability, Storage, logistics challenges, Huge capex requirement for purchasing farm Machniaries, opex cost of biomass depot & lack of Govt Policies in place.
Roles of stakeholders and challenges associated:
There are 3 stakeholders associated with agro-waste supply chain as follows:
Farmers/aggregators contribute towards aggregation of agro-waste from fields and further transportation of it to the owners.
Challenges with farmers:
- 85% of farmers in India are Small and marginal & are not equipped with farm machinaries, transportation facilities.
- The narrow aggregation period & lack of economic incentives for biomass, makes it prone for stubble burning in fields.
Challenges with aggregators:
- Huge cost incurred in terms of equipment, land rentals for biomass storage, biomass insurance & firefighting arrangments is in built in the cost offered makes it unviable.
Plant Owners play crucial role in setting-up commercially viable plants.
Challenges associated with owners:
- In many parts of India, farm mechanisation is in the nascent stage so agro-waste aggregation is a challenge.
- Huge requirement of land for setting-up plant and biomass depots poses higher land rentals.
- Unproven and limited technology are available.
- Disposal of byproducts like:Fermented Organic Manure & flyash is a challenge.
- There is no price fixation/formulation mechanism in place for purchasing agro-waste & selling 2G Ethanol.
District Administartion plays a crucial role in liasioning between farmer and owners & formulating suitable policies for successful execution.
- Challenges with Dist Admin: Transfer of technologies from lab to field by creating awareness among beneficiaries & monitering the project progress with ground reality.
Potential solution:
- The allocation of barren land/Panchayati land/waste land for development of Biomass depots can reduce the storage cost to farmers/aggregators/owners which will make supply chain viable.
- The modified tractor trollies should be included in Farm Mechanisation Schemes and additional subsidy on farm equipment should be given which will motivate farmers.
- To foster the robust biomass ecosystem, Biomass pricing or benchmarking with respect to Methane content/Calorific value associated with it should also be done like in the case of Briquettes.
- From Government part, collaboration with foreign parties must be made for effective and proven Technologies suitable as per Indian Agro-climatic conditions. More investment on R & D sector.
- Conclusion:
Although biofuel business is having many challenges associated, they can still ensure a healthy environment, reduce import dependency on fossil fuels, employment generation and additional income for farmers through crop incentivisations. The Government of India must look into the sustainable production of biofuels with feasible, clear policy and financial support to make India a global champion.
Strategizing carbon neutral technologies & Ratification of International-Climate-Change Paris Agreement under UNFCCC, COP are critical drivers to promulgate carbon neutrality & holistic net Zero goal with Bio-gas as a potential candidate. Novel Heterogeneous Catalysis plays crucial role for selective oxidation of hydrogen sulphide (H₂S) to elemental sulphur (S) in bio-gas purification & is of paramount interest globally.
Bio-gas (primarily methane & carbon dioxide) is produced by Anaerobic Digestion (AD) of wet organic rich biomass. However, generated intermediate like hydrogen sulfide, ammonia, carbon dioxide, siloxanes & halogens lowers quality, selectivity & yield of harvested bio-gas. H₂S is notorious as it is toxic & corrosive. Selective Oxidation of H₂S to S using metal oxide-based catalysts (Vanadium & Iron oxides) & Carbon-based catalysts improves bio-gas quality, operational efficiency & prevents equipment damage.
Present paper critically reviews heterogeneous catalytic processes for Selective Oxidation of H₂S to elemental S in bio-gas contributing to sustainable & circular carbon economy. Advanced catalytic systems with robust reactor internals catering to optimised reaction parameters like temperature, O2/H2S ratio & H2O content affecting catalytic performance are analysed. Present paper elaborate parameters of catalysis in selective oxidation like catalyst efficiency, scalability, active sites regenerability, stability, adsorption strength, surface-to-volume ratio, metal-metal & metal support interaction & synergy of support with active metal sites being prudent factors of analysis including role of catalyst modifiers, inhibitors & enhancers.
Predictions of tailored heterogeneous active catalyst formulations for economic viability of selective oxidation technologies are elaborated with Noble/ non-noble catalysts support modifiers & enhancers (like magnesium, lanthanum, cobalt and chromium) that enhances gasification of coke precursors & slows coking surface reactions. Selectivity enhancement of catalysts by inhibiting thermodynamically unfavourable side reactions for desired conversion pathways; enhanced process energy efficiency due to more efficient catalysts with lower temperatures & pressures (due to altered activation energy); catalyst recyclability & reusability supplementing overall economics & environmental process impact; catalyst compatibility with impurities / contaminants laden feedstock and thereby being resistant to deactivation / poisoning by impurities and catalyst mechanism in bio-gas purification are discussed.
Study of Novel Heterogeneous catalysis for oxidation of H₂S to elemental S aims to establish that catalytic processes can be promising pathways for producing clean & industrially viable biogas & for pathways of producing VACs (Value Added Chemicals) from bio-gas. In Comparison, economic feasibility supplemented with positive green societal costs projects catalysis for biogas purification with in-situ integration of carbon neutral perspective. Hope this compilation will create lots of interest amongst researcher & practicing engineers active in Sulphur removal, Bio-fuels, Industrialist and environmentalist towards meeting net zero goals.
Bio-gas (primarily methane & carbon dioxide) is produced by Anaerobic Digestion (AD) of wet organic rich biomass. However, generated intermediate like hydrogen sulfide, ammonia, carbon dioxide, siloxanes & halogens lowers quality, selectivity & yield of harvested bio-gas. H₂S is notorious as it is toxic & corrosive. Selective Oxidation of H₂S to S using metal oxide-based catalysts (Vanadium & Iron oxides) & Carbon-based catalysts improves bio-gas quality, operational efficiency & prevents equipment damage.
Present paper critically reviews heterogeneous catalytic processes for Selective Oxidation of H₂S to elemental S in bio-gas contributing to sustainable & circular carbon economy. Advanced catalytic systems with robust reactor internals catering to optimised reaction parameters like temperature, O2/H2S ratio & H2O content affecting catalytic performance are analysed. Present paper elaborate parameters of catalysis in selective oxidation like catalyst efficiency, scalability, active sites regenerability, stability, adsorption strength, surface-to-volume ratio, metal-metal & metal support interaction & synergy of support with active metal sites being prudent factors of analysis including role of catalyst modifiers, inhibitors & enhancers.
Predictions of tailored heterogeneous active catalyst formulations for economic viability of selective oxidation technologies are elaborated with Noble/ non-noble catalysts support modifiers & enhancers (like magnesium, lanthanum, cobalt and chromium) that enhances gasification of coke precursors & slows coking surface reactions. Selectivity enhancement of catalysts by inhibiting thermodynamically unfavourable side reactions for desired conversion pathways; enhanced process energy efficiency due to more efficient catalysts with lower temperatures & pressures (due to altered activation energy); catalyst recyclability & reusability supplementing overall economics & environmental process impact; catalyst compatibility with impurities / contaminants laden feedstock and thereby being resistant to deactivation / poisoning by impurities and catalyst mechanism in bio-gas purification are discussed.
Study of Novel Heterogeneous catalysis for oxidation of H₂S to elemental S aims to establish that catalytic processes can be promising pathways for producing clean & industrially viable biogas & for pathways of producing VACs (Value Added Chemicals) from bio-gas. In Comparison, economic feasibility supplemented with positive green societal costs projects catalysis for biogas purification with in-situ integration of carbon neutral perspective. Hope this compilation will create lots of interest amongst researcher & practicing engineers active in Sulphur removal, Bio-fuels, Industrialist and environmentalist towards meeting net zero goals.
The global transition toward sustainable energy demands innovative pathways that simultaneously address waste management and clean energy generation. Microbial valorization of lignocellulosic waste offers a scalable and eco-friendly solution to these challenges, advancing the circular economy while diversifying energy resources.
This work presents advancements in using thermophilic bacteria to transform agricultural residues into value-added feedstocks. In our recent studies, a thermophilic Geobacillus strain demonstrated efficient enzymatic hydrolysis of xylan, releasing approximately 4 g/L of xylose from an initial 10 g/L substrate concentration. Notably, the strain exhibited limited xylose consumption and variable acid production, resulting in xylose accumulation in the medium.
The limited metabolic use of xylose by this strain suggests a strategic advantage: enhancing bioethanol yields when integrated with xylose-fermenting yeasts, as higher free xylose availability improves fermentation efficiency. Furthermore, the thermophilic properties of the strain enable operation under harsh industrial conditions, reducing pretreatment intensity and energy requirements.
We also explored co-cultivation strategies to simulate bioethanol production environments, demonstrating improved energy yields and greater process stability. Integrating microbial biotechnology into energy systems not only boosts feedstock valorization but also significantly reduces greenhouse gas emissions, supporting decentralized, sustainable, and adaptable energy solutions. This study highlights microbial valorization as a key enabler for advancing biofuels as a versatile and sustainable feedstock in future energy systems.
Co-author/s:
Fatemeh Yazdian, Associate Professor, University of Tehran.
Zahra Etemadifar, Associate Professor, University of Isfahan.
Mohammad J. Taherzadeh, Professor, University of Boras.
This work presents advancements in using thermophilic bacteria to transform agricultural residues into value-added feedstocks. In our recent studies, a thermophilic Geobacillus strain demonstrated efficient enzymatic hydrolysis of xylan, releasing approximately 4 g/L of xylose from an initial 10 g/L substrate concentration. Notably, the strain exhibited limited xylose consumption and variable acid production, resulting in xylose accumulation in the medium.
The limited metabolic use of xylose by this strain suggests a strategic advantage: enhancing bioethanol yields when integrated with xylose-fermenting yeasts, as higher free xylose availability improves fermentation efficiency. Furthermore, the thermophilic properties of the strain enable operation under harsh industrial conditions, reducing pretreatment intensity and energy requirements.
We also explored co-cultivation strategies to simulate bioethanol production environments, demonstrating improved energy yields and greater process stability. Integrating microbial biotechnology into energy systems not only boosts feedstock valorization but also significantly reduces greenhouse gas emissions, supporting decentralized, sustainable, and adaptable energy solutions. This study highlights microbial valorization as a key enabler for advancing biofuels as a versatile and sustainable feedstock in future energy systems.
Co-author/s:
Fatemeh Yazdian, Associate Professor, University of Tehran.
Zahra Etemadifar, Associate Professor, University of Isfahan.
Mohammad J. Taherzadeh, Professor, University of Boras.
Microbial fuel cells (MFCs) represent a promising and sustainable technology for the conversion of bioenergy resources, particularly in the areas of wastewater treatment and biohydrogen production. By leveraging the metabolic activities of microorganisms, MFCs offer a unique method for generating electricity through the oxidation of organic substrates. Recent innovations have enabled the enhancement of MFC performance, such as optimizing microbial consortia, electrode materials, and environmental conditions, to achieve higher energy outputs and Coulombic efficiency. In addition to their application in energy production, MFCs are increasingly recognized for their role in addressing wastewater treatment challenges, effectively degrading organic compounds and reducing the environmental footprint of industrial effluents. Furthermore, MFCs can be adapted to produce biohydrogen, a valuable alternative fuel, by utilizing electrochemical processes that overcome thermodynamic barriers. The integration of MFCs into bioenergy systems represents a transformative approach, utilizing organic waste as a resource for both energy generation and environmental remediation. These advancements underscore the potential of MFCs in contributing to the global transition towards sustainable energy solutions, offering a versatile and eco-friendly alternative to traditional power generation methods.
Keywords: Biohydrogen, Biomass conversion, Microbial fuel cells (MFCs), Wastewater treatment, Renewable energy.
Co-author/s:
Mohammad Reza Rahimpour, Professor of Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Fatemeh Haghighatjoo, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Eng. Maryam Koohi-Saadi, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Keywords: Biohydrogen, Biomass conversion, Microbial fuel cells (MFCs), Wastewater treatment, Renewable energy.
Co-author/s:
Mohammad Reza Rahimpour, Professor of Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Fatemeh Haghighatjoo, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Eng. Maryam Koohi-Saadi, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
The chemical industry is the third largest CO2 emitter globally and given its intricate dependence on carbon-based materials, it is hard to abate. Bio-feedstocks can replace many conventional petrochemical feedstocks in key value chains, from C2 to C6+ in a diverse range of applications, making them one of the quickest and more efficient ways to decarbonize the chemical industry. Although it is early days as the technologies are being scaled up to cater to bigger volumes, bio-based chemicals (also known as green chemicals) are sought by big energy corporations willing to meet their ESG targets. S&P Global tracks the latest developments in this industry, from the crops to the finished products and will provide the audience with an overview of the key issues facing the industry.
The global demand for biofuels has significantly increased in recent years due to their potential to reduce greenhouse gas emissions and provide an environmentally friendly alternative to fossil fuels. Among biofuels, bioethanol has emerged as a key candidate for sustainable energy solutions, offering numerous benefits in terms of energy security, economic growth, and environmental preservation. However, the production and purification of bioethanol still face numerous challenges, particularly in terms of energy efficiency and cost. To address these issues, recent advancements in membrane technology have provided promising alternatives to conventional ethanol purification methods. Membrane-based processes such as pervaporation, reverse osmosis, and ultrafiltration are being increasingly integrated into bioethanol production to optimize energy usage and reduce operational costs. These processes, especially when combined with bioreactor technologies, enhance the overall efficiency of bioethanol production by enabling selective separation, high throughput, and the reduction of waste products. Moreover, innovations in mixed matrix membranes (MMMs) and the incorporation of nanomaterials such as carbon nanotubes are further improving the performance and scalability of these systems. The continued development and optimization of these membrane technologies are expected to play a pivotal role in the future of bioethanol production, making it more sustainable and economically viable.
Keywords: Bioreactors, Bioethanol, Membrane Technology, Pervaporation, Sustainability
Co-author/s:
Mohammad Reza Rahimpour, Professor of Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Soheila Zandi Lak, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Eng. Maryam Koohi-Saadi, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Keywords: Bioreactors, Bioethanol, Membrane Technology, Pervaporation, Sustainability
Co-author/s:
Mohammad Reza Rahimpour, Professor of Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Soheila Zandi Lak, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Eng. Maryam Koohi-Saadi, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Biochar, a carbon-rich residue derived from the pyrolysis of biomass, presents a transformative opportunity for enhancing the performance and sustainability of Compressed Biogas (CBG) plants. Its integration into anaerobic digestion significantly improves methane yield—by up to 74%—by supporting methanogenic microbes, stabilizing pH, and adsorbing inhibitors like ammonia and Volatile Fatty Acids. This leads to improved digester stability, reduced downtime, and enhanced energy yields—key parameters for the viability of CBG operations.
Beyond process efficiency, biochar enables the upcycling of anaerobic digestate into a high-value biofertilizer. Its porous structure and high cation exchange capacity aid in nutrient retention, heavy metal immobilization, and reduction of greenhouse gas emissions post-application. This not only creates a secondary revenue stream but also supports sustainable agricultural practices.
For GAIL, the integration of biochar offers a circular economy model—converting organic waste into renewable energy and climate-positive soil amendments. Furthermore, the carbon sequestration potential of biochar contributes to emission reduction goals and the generation of high-quality carbon credits. Environmental benefits include carbon sequestration (1.15–1.20 tCO₂eq/ton biochar) and reduced soil emissions. Pilot studies and scalable deployment pathways demonstrate biochar’s potential to play a critical role in India’s clean energy and climate transition.
Beyond process efficiency, biochar enables the upcycling of anaerobic digestate into a high-value biofertilizer. Its porous structure and high cation exchange capacity aid in nutrient retention, heavy metal immobilization, and reduction of greenhouse gas emissions post-application. This not only creates a secondary revenue stream but also supports sustainable agricultural practices.
For GAIL, the integration of biochar offers a circular economy model—converting organic waste into renewable energy and climate-positive soil amendments. Furthermore, the carbon sequestration potential of biochar contributes to emission reduction goals and the generation of high-quality carbon credits. Environmental benefits include carbon sequestration (1.15–1.20 tCO₂eq/ton biochar) and reduced soil emissions. Pilot studies and scalable deployment pathways demonstrate biochar’s potential to play a critical role in India’s clean energy and climate transition.
The increasing demand for sustainable energy sources has spurred significant research into syngas conversion technologies, particularly for the production of biofuels. Syngas, a mixture of carbon monoxide (CO) and hydrogen (H2), is generated through the gasification of biomass and other organic materials and serves as a key feedstock for biofuel production. This paper explores various methods for converting syngas into valuable biofuels, including bioethanol, biomethanol, biohydrogen, and biobutanol. The Fischer-Tropsch (FT) process, utilizing metal catalysts, and syngas fermentation, employing microbial catalysts, are two prominent techniques discussed in detail. The FT process is a well-established method that converts syngas into liquid hydrocarbons, including diesel and gasoline, using catalysts like cobalt and iron. In contrast, syngas fermentation offers a biologically driven alternative, utilizing microorganisms to directly convert syngas into ethanol and other valuable by-products. The paper further examines the challenges and advantages associated with these processes, focusing on factors such as catalyst efficiency, process conditions, and the potential for scale-up. It also addresses the economic and environmental implications of syngas-derived biofuels, emphasizing the need for optimized reactor designs and improved mass transfer rates. The paper concludes with an outlook on the future of syngas conversion technologies, highlighting the potential for biofuels to play a central role in the transition towards a sustainable energy future.
Keywords: Biomethanol, Biohydrogen, Bioethanol, Fischer-Tropsch, Syngas fermentation
Co-author/s:
Fatemeh Haghighatjoo, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Soheila Zandi Lak, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Eng. Maryam Koohi-Saadi, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Keywords: Biomethanol, Biohydrogen, Bioethanol, Fischer-Tropsch, Syngas fermentation
Co-author/s:
Fatemeh Haghighatjoo, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Soheila Zandi Lak, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Eng. Maryam Koohi-Saadi, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Elena Hajekova
Vice Chair
Deputy Head, Department of Organic Technology, Catalysis & Petroleum Technology
Slovak University of Technology
Alena Kravtsova
Vice Chair
Director, Financial Advisory, Energy, Resources & Industrials
Deloitte
The chemical industry is the third largest CO2 emitter globally and given its intricate dependence on carbon-based materials, it is hard to abate. Bio-feedstocks can replace many conventional petrochemical feedstocks in key value chains, from C2 to C6+ in a diverse range of applications, making them one of the quickest and more efficient ways to decarbonize the chemical industry. Although it is early days as the technologies are being scaled up to cater to bigger volumes, bio-based chemicals (also known as green chemicals) are sought by big energy corporations willing to meet their ESG targets. S&P Global tracks the latest developments in this industry, from the crops to the finished products and will provide the audience with an overview of the key issues facing the industry.
Biochar, a carbon-rich residue derived from the pyrolysis of biomass, presents a transformative opportunity for enhancing the performance and sustainability of Compressed Biogas (CBG) plants. Its integration into anaerobic digestion significantly improves methane yield—by up to 74%—by supporting methanogenic microbes, stabilizing pH, and adsorbing inhibitors like ammonia and Volatile Fatty Acids. This leads to improved digester stability, reduced downtime, and enhanced energy yields—key parameters for the viability of CBG operations.
Beyond process efficiency, biochar enables the upcycling of anaerobic digestate into a high-value biofertilizer. Its porous structure and high cation exchange capacity aid in nutrient retention, heavy metal immobilization, and reduction of greenhouse gas emissions post-application. This not only creates a secondary revenue stream but also supports sustainable agricultural practices.
For GAIL, the integration of biochar offers a circular economy model—converting organic waste into renewable energy and climate-positive soil amendments. Furthermore, the carbon sequestration potential of biochar contributes to emission reduction goals and the generation of high-quality carbon credits. Environmental benefits include carbon sequestration (1.15–1.20 tCO₂eq/ton biochar) and reduced soil emissions. Pilot studies and scalable deployment pathways demonstrate biochar’s potential to play a critical role in India’s clean energy and climate transition.
Beyond process efficiency, biochar enables the upcycling of anaerobic digestate into a high-value biofertilizer. Its porous structure and high cation exchange capacity aid in nutrient retention, heavy metal immobilization, and reduction of greenhouse gas emissions post-application. This not only creates a secondary revenue stream but also supports sustainable agricultural practices.
For GAIL, the integration of biochar offers a circular economy model—converting organic waste into renewable energy and climate-positive soil amendments. Furthermore, the carbon sequestration potential of biochar contributes to emission reduction goals and the generation of high-quality carbon credits. Environmental benefits include carbon sequestration (1.15–1.20 tCO₂eq/ton biochar) and reduced soil emissions. Pilot studies and scalable deployment pathways demonstrate biochar’s potential to play a critical role in India’s clean energy and climate transition.
Fatemeh Haghighatjoo
Speaker
Researcher in Chemical Engineering
Department of Chemical Engineering, Shiraz University, Shiraz, Iran
The global demand for biofuels has significantly increased in recent years due to their potential to reduce greenhouse gas emissions and provide an environmentally friendly alternative to fossil fuels. Among biofuels, bioethanol has emerged as a key candidate for sustainable energy solutions, offering numerous benefits in terms of energy security, economic growth, and environmental preservation. However, the production and purification of bioethanol still face numerous challenges, particularly in terms of energy efficiency and cost. To address these issues, recent advancements in membrane technology have provided promising alternatives to conventional ethanol purification methods. Membrane-based processes such as pervaporation, reverse osmosis, and ultrafiltration are being increasingly integrated into bioethanol production to optimize energy usage and reduce operational costs. These processes, especially when combined with bioreactor technologies, enhance the overall efficiency of bioethanol production by enabling selective separation, high throughput, and the reduction of waste products. Moreover, innovations in mixed matrix membranes (MMMs) and the incorporation of nanomaterials such as carbon nanotubes are further improving the performance and scalability of these systems. The continued development and optimization of these membrane technologies are expected to play a pivotal role in the future of bioethanol production, making it more sustainable and economically viable.
Keywords: Bioreactors, Bioethanol, Membrane Technology, Pervaporation, Sustainability
Co-author/s:
Mohammad Reza Rahimpour, Professor of Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Soheila Zandi Lak, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Eng. Maryam Koohi-Saadi, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Keywords: Bioreactors, Bioethanol, Membrane Technology, Pervaporation, Sustainability
Co-author/s:
Mohammad Reza Rahimpour, Professor of Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Soheila Zandi Lak, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Eng. Maryam Koohi-Saadi, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Sharareh Harirchi
Speaker
Assistant Professor
Iranian Research Organization for Science and Technology
The global transition toward sustainable energy demands innovative pathways that simultaneously address waste management and clean energy generation. Microbial valorization of lignocellulosic waste offers a scalable and eco-friendly solution to these challenges, advancing the circular economy while diversifying energy resources.
This work presents advancements in using thermophilic bacteria to transform agricultural residues into value-added feedstocks. In our recent studies, a thermophilic Geobacillus strain demonstrated efficient enzymatic hydrolysis of xylan, releasing approximately 4 g/L of xylose from an initial 10 g/L substrate concentration. Notably, the strain exhibited limited xylose consumption and variable acid production, resulting in xylose accumulation in the medium.
The limited metabolic use of xylose by this strain suggests a strategic advantage: enhancing bioethanol yields when integrated with xylose-fermenting yeasts, as higher free xylose availability improves fermentation efficiency. Furthermore, the thermophilic properties of the strain enable operation under harsh industrial conditions, reducing pretreatment intensity and energy requirements.
We also explored co-cultivation strategies to simulate bioethanol production environments, demonstrating improved energy yields and greater process stability. Integrating microbial biotechnology into energy systems not only boosts feedstock valorization but also significantly reduces greenhouse gas emissions, supporting decentralized, sustainable, and adaptable energy solutions. This study highlights microbial valorization as a key enabler for advancing biofuels as a versatile and sustainable feedstock in future energy systems.
Co-author/s:
Fatemeh Yazdian, Associate Professor, University of Tehran.
Zahra Etemadifar, Associate Professor, University of Isfahan.
Mohammad J. Taherzadeh, Professor, University of Boras.
This work presents advancements in using thermophilic bacteria to transform agricultural residues into value-added feedstocks. In our recent studies, a thermophilic Geobacillus strain demonstrated efficient enzymatic hydrolysis of xylan, releasing approximately 4 g/L of xylose from an initial 10 g/L substrate concentration. Notably, the strain exhibited limited xylose consumption and variable acid production, resulting in xylose accumulation in the medium.
The limited metabolic use of xylose by this strain suggests a strategic advantage: enhancing bioethanol yields when integrated with xylose-fermenting yeasts, as higher free xylose availability improves fermentation efficiency. Furthermore, the thermophilic properties of the strain enable operation under harsh industrial conditions, reducing pretreatment intensity and energy requirements.
We also explored co-cultivation strategies to simulate bioethanol production environments, demonstrating improved energy yields and greater process stability. Integrating microbial biotechnology into energy systems not only boosts feedstock valorization but also significantly reduces greenhouse gas emissions, supporting decentralized, sustainable, and adaptable energy solutions. This study highlights microbial valorization as a key enabler for advancing biofuels as a versatile and sustainable feedstock in future energy systems.
Co-author/s:
Fatemeh Yazdian, Associate Professor, University of Tehran.
Zahra Etemadifar, Associate Professor, University of Isfahan.
Mohammad J. Taherzadeh, Professor, University of Boras.
Kiran Kothari
Speaker
Senior Manager-Biofuel Operations
Hindustan Petroleum Corporation Limited
Objective:
India is an agrarian economy with immense potential og agro-waste for sustainable energy production. Tapping this potential will make India Self-sustained in terms of Energy demand and will contribute towards Socio-economic & Environmental Development. However, efficient & effective management of agro-waste poses many challenges w.r.t Seasonal Availability, Storage, logistics challenges, Huge capex requirement for purchasing farm Machniaries, opex cost of biomass depot & lack of Govt Policies in place.
Roles of stakeholders and challenges associated:
There are 3 stakeholders associated with agro-waste supply chain as follows:
Farmers/aggregators contribute towards aggregation of agro-waste from fields and further transportation of it to the owners.
Challenges with farmers:
Challenges with aggregators:
Plant Owners play crucial role in setting-up commercially viable plants.
Challenges associated with owners:
District Administartion plays a crucial role in liasioning between farmer and owners & formulating suitable policies for successful execution.
Potential solution:
Although biofuel business is having many challenges associated, they can still ensure a healthy environment, reduce import dependency on fossil fuels, employment generation and additional income for farmers through crop incentivisations. The Government of India must look into the sustainable production of biofuels with feasible, clear policy and financial support to make India a global champion.
India is an agrarian economy with immense potential og agro-waste for sustainable energy production. Tapping this potential will make India Self-sustained in terms of Energy demand and will contribute towards Socio-economic & Environmental Development. However, efficient & effective management of agro-waste poses many challenges w.r.t Seasonal Availability, Storage, logistics challenges, Huge capex requirement for purchasing farm Machniaries, opex cost of biomass depot & lack of Govt Policies in place.
Roles of stakeholders and challenges associated:
There are 3 stakeholders associated with agro-waste supply chain as follows:
Farmers/aggregators contribute towards aggregation of agro-waste from fields and further transportation of it to the owners.
Challenges with farmers:
- 85% of farmers in India are Small and marginal & are not equipped with farm machinaries, transportation facilities.
- The narrow aggregation period & lack of economic incentives for biomass, makes it prone for stubble burning in fields.
Challenges with aggregators:
- Huge cost incurred in terms of equipment, land rentals for biomass storage, biomass insurance & firefighting arrangments is in built in the cost offered makes it unviable.
Plant Owners play crucial role in setting-up commercially viable plants.
Challenges associated with owners:
- In many parts of India, farm mechanisation is in the nascent stage so agro-waste aggregation is a challenge.
- Huge requirement of land for setting-up plant and biomass depots poses higher land rentals.
- Unproven and limited technology are available.
- Disposal of byproducts like:Fermented Organic Manure & flyash is a challenge.
- There is no price fixation/formulation mechanism in place for purchasing agro-waste & selling 2G Ethanol.
District Administartion plays a crucial role in liasioning between farmer and owners & formulating suitable policies for successful execution.
- Challenges with Dist Admin: Transfer of technologies from lab to field by creating awareness among beneficiaries & monitering the project progress with ground reality.
Potential solution:
- The allocation of barren land/Panchayati land/waste land for development of Biomass depots can reduce the storage cost to farmers/aggregators/owners which will make supply chain viable.
- The modified tractor trollies should be included in Farm Mechanisation Schemes and additional subsidy on farm equipment should be given which will motivate farmers.
- To foster the robust biomass ecosystem, Biomass pricing or benchmarking with respect to Methane content/Calorific value associated with it should also be done like in the case of Briquettes.
- From Government part, collaboration with foreign parties must be made for effective and proven Technologies suitable as per Indian Agro-climatic conditions. More investment on R & D sector.
- Conclusion:
Although biofuel business is having many challenges associated, they can still ensure a healthy environment, reduce import dependency on fossil fuels, employment generation and additional income for farmers through crop incentivisations. The Government of India must look into the sustainable production of biofuels with feasible, clear policy and financial support to make India a global champion.
After a decade-long tardy progress, the Ethanol Blending program in India started on a progressive pathway, and there has been consistent improvement in ethanol-fuel blending ratios since then, primarily due to diversification in first-generation ethanol feedstocks. India now aims to achieve a 30% ethanol fuel blending ratio in the coming years, which requires stringent planning and policy support to meet the rising demand for ethanol. With emphasis on second-generation (2G) ethanol production (from non-edible feedstocks), the Government launched a financial support scheme, Pradhan Mantri JI-VAN (Jaiv Indhan- Vatavaran Anukool fasal awashesh Nivaran) Yojana, to the tune of 230 million USD for setting up twelve integrated 2G Bio-ethanol Projects for the period 2018-19 to 2023-24. However, the issue of higher production cost of 2G ethanol makes it difficult for the oil marketing companies (OMCs) to absorb the additional cost and makes it economically unviable for adoption. This paper examines the role of techniques in production processes as well as the development of carbon markets in the production of 2G ethanol that can make it viable for long-term adoption.
Through forecasting techniques, we calculate the future ethanol requirement vis-à-vis gasoline demand while taking into account the impact of energy transition through other alternative energy sources. We then assess the environmental and economic impacts of 2G ethanol with the help of simulation, scenario, and sensitivity analysis. We then re-evaluate and compare the economic impact, taking into account carbon credits that can be generated through the adoption of 2G ethanol.
Results indicate that the cost of 2G ethanol production decreases with time. This cost decreases significantly in the case of setting up an integrated bio-refinery in place of a standalone biorefinery. However, this decrease is not enough to compensate or compete with the 1G (first generation) ethanol or petrol prices. However, while taking into consideration the social cost of carbon, the second-generation ethanol becomes economically viable when carbon credit accounting is incorporated in the economic analysis. The results are also helpful in suggesting policy measures that can aid in the long-term successful adoption of 2G ethanol.
The paper indicates the growing importance of carbon markets, which are all set to launch in India in 2026. The techno-economic analysis provides insights with regard to the impact of the process adopted for 2G ethanol production on its long-term adoption and viability. The paper also successfully highlights the importance of ethanol fuel in helping to achieve decarbonisation and strengthen energy security. Further, the ambitious targets of switching to an ethanol economy cannot be achieved alone by 1G ethanol.
Through forecasting techniques, we calculate the future ethanol requirement vis-à-vis gasoline demand while taking into account the impact of energy transition through other alternative energy sources. We then assess the environmental and economic impacts of 2G ethanol with the help of simulation, scenario, and sensitivity analysis. We then re-evaluate and compare the economic impact, taking into account carbon credits that can be generated through the adoption of 2G ethanol.
Results indicate that the cost of 2G ethanol production decreases with time. This cost decreases significantly in the case of setting up an integrated bio-refinery in place of a standalone biorefinery. However, this decrease is not enough to compensate or compete with the 1G (first generation) ethanol or petrol prices. However, while taking into consideration the social cost of carbon, the second-generation ethanol becomes economically viable when carbon credit accounting is incorporated in the economic analysis. The results are also helpful in suggesting policy measures that can aid in the long-term successful adoption of 2G ethanol.
The paper indicates the growing importance of carbon markets, which are all set to launch in India in 2026. The techno-economic analysis provides insights with regard to the impact of the process adopted for 2G ethanol production on its long-term adoption and viability. The paper also successfully highlights the importance of ethanol fuel in helping to achieve decarbonisation and strengthen energy security. Further, the ambitious targets of switching to an ethanol economy cannot be achieved alone by 1G ethanol.
Strategizing carbon neutral technologies & Ratification of International-Climate-Change Paris Agreement under UNFCCC, COP are critical drivers to promulgate carbon neutrality & holistic net Zero goal with Bio-gas as a potential candidate. Novel Heterogeneous Catalysis plays crucial role for selective oxidation of hydrogen sulphide (H₂S) to elemental sulphur (S) in bio-gas purification & is of paramount interest globally.
Bio-gas (primarily methane & carbon dioxide) is produced by Anaerobic Digestion (AD) of wet organic rich biomass. However, generated intermediate like hydrogen sulfide, ammonia, carbon dioxide, siloxanes & halogens lowers quality, selectivity & yield of harvested bio-gas. H₂S is notorious as it is toxic & corrosive. Selective Oxidation of H₂S to S using metal oxide-based catalysts (Vanadium & Iron oxides) & Carbon-based catalysts improves bio-gas quality, operational efficiency & prevents equipment damage.
Present paper critically reviews heterogeneous catalytic processes for Selective Oxidation of H₂S to elemental S in bio-gas contributing to sustainable & circular carbon economy. Advanced catalytic systems with robust reactor internals catering to optimised reaction parameters like temperature, O2/H2S ratio & H2O content affecting catalytic performance are analysed. Present paper elaborate parameters of catalysis in selective oxidation like catalyst efficiency, scalability, active sites regenerability, stability, adsorption strength, surface-to-volume ratio, metal-metal & metal support interaction & synergy of support with active metal sites being prudent factors of analysis including role of catalyst modifiers, inhibitors & enhancers.
Predictions of tailored heterogeneous active catalyst formulations for economic viability of selective oxidation technologies are elaborated with Noble/ non-noble catalysts support modifiers & enhancers (like magnesium, lanthanum, cobalt and chromium) that enhances gasification of coke precursors & slows coking surface reactions. Selectivity enhancement of catalysts by inhibiting thermodynamically unfavourable side reactions for desired conversion pathways; enhanced process energy efficiency due to more efficient catalysts with lower temperatures & pressures (due to altered activation energy); catalyst recyclability & reusability supplementing overall economics & environmental process impact; catalyst compatibility with impurities / contaminants laden feedstock and thereby being resistant to deactivation / poisoning by impurities and catalyst mechanism in bio-gas purification are discussed.
Study of Novel Heterogeneous catalysis for oxidation of H₂S to elemental S aims to establish that catalytic processes can be promising pathways for producing clean & industrially viable biogas & for pathways of producing VACs (Value Added Chemicals) from bio-gas. In Comparison, economic feasibility supplemented with positive green societal costs projects catalysis for biogas purification with in-situ integration of carbon neutral perspective. Hope this compilation will create lots of interest amongst researcher & practicing engineers active in Sulphur removal, Bio-fuels, Industrialist and environmentalist towards meeting net zero goals.
Bio-gas (primarily methane & carbon dioxide) is produced by Anaerobic Digestion (AD) of wet organic rich biomass. However, generated intermediate like hydrogen sulfide, ammonia, carbon dioxide, siloxanes & halogens lowers quality, selectivity & yield of harvested bio-gas. H₂S is notorious as it is toxic & corrosive. Selective Oxidation of H₂S to S using metal oxide-based catalysts (Vanadium & Iron oxides) & Carbon-based catalysts improves bio-gas quality, operational efficiency & prevents equipment damage.
Present paper critically reviews heterogeneous catalytic processes for Selective Oxidation of H₂S to elemental S in bio-gas contributing to sustainable & circular carbon economy. Advanced catalytic systems with robust reactor internals catering to optimised reaction parameters like temperature, O2/H2S ratio & H2O content affecting catalytic performance are analysed. Present paper elaborate parameters of catalysis in selective oxidation like catalyst efficiency, scalability, active sites regenerability, stability, adsorption strength, surface-to-volume ratio, metal-metal & metal support interaction & synergy of support with active metal sites being prudent factors of analysis including role of catalyst modifiers, inhibitors & enhancers.
Predictions of tailored heterogeneous active catalyst formulations for economic viability of selective oxidation technologies are elaborated with Noble/ non-noble catalysts support modifiers & enhancers (like magnesium, lanthanum, cobalt and chromium) that enhances gasification of coke precursors & slows coking surface reactions. Selectivity enhancement of catalysts by inhibiting thermodynamically unfavourable side reactions for desired conversion pathways; enhanced process energy efficiency due to more efficient catalysts with lower temperatures & pressures (due to altered activation energy); catalyst recyclability & reusability supplementing overall economics & environmental process impact; catalyst compatibility with impurities / contaminants laden feedstock and thereby being resistant to deactivation / poisoning by impurities and catalyst mechanism in bio-gas purification are discussed.
Study of Novel Heterogeneous catalysis for oxidation of H₂S to elemental S aims to establish that catalytic processes can be promising pathways for producing clean & industrially viable biogas & for pathways of producing VACs (Value Added Chemicals) from bio-gas. In Comparison, economic feasibility supplemented with positive green societal costs projects catalysis for biogas purification with in-situ integration of carbon neutral perspective. Hope this compilation will create lots of interest amongst researcher & practicing engineers active in Sulphur removal, Bio-fuels, Industrialist and environmentalist towards meeting net zero goals.
Mohammad Reza Rahimpour (duplicate)
Speaker
Professor of Chemical Engineering
Department of Chemical Engineering, Shiraz University, Shiraz, Iran
The increasing demand for sustainable energy sources has spurred significant research into syngas conversion technologies, particularly for the production of biofuels. Syngas, a mixture of carbon monoxide (CO) and hydrogen (H2), is generated through the gasification of biomass and other organic materials and serves as a key feedstock for biofuel production. This paper explores various methods for converting syngas into valuable biofuels, including bioethanol, biomethanol, biohydrogen, and biobutanol. The Fischer-Tropsch (FT) process, utilizing metal catalysts, and syngas fermentation, employing microbial catalysts, are two prominent techniques discussed in detail. The FT process is a well-established method that converts syngas into liquid hydrocarbons, including diesel and gasoline, using catalysts like cobalt and iron. In contrast, syngas fermentation offers a biologically driven alternative, utilizing microorganisms to directly convert syngas into ethanol and other valuable by-products. The paper further examines the challenges and advantages associated with these processes, focusing on factors such as catalyst efficiency, process conditions, and the potential for scale-up. It also addresses the economic and environmental implications of syngas-derived biofuels, emphasizing the need for optimized reactor designs and improved mass transfer rates. The paper concludes with an outlook on the future of syngas conversion technologies, highlighting the potential for biofuels to play a central role in the transition towards a sustainable energy future.
Keywords: Biomethanol, Biohydrogen, Bioethanol, Fischer-Tropsch, Syngas fermentation
Co-author/s:
Fatemeh Haghighatjoo, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Soheila Zandi Lak, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Eng. Maryam Koohi-Saadi, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Keywords: Biomethanol, Biohydrogen, Bioethanol, Fischer-Tropsch, Syngas fermentation
Co-author/s:
Fatemeh Haghighatjoo, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Soheila Zandi Lak, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Eng. Maryam Koohi-Saadi, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Soheila Zandi Lak
Speaker
Researcher in Chemical Engineering
Department of Chemical Engineering, Shiraz University, Shiraz, Iran
Microbial fuel cells (MFCs) represent a promising and sustainable technology for the conversion of bioenergy resources, particularly in the areas of wastewater treatment and biohydrogen production. By leveraging the metabolic activities of microorganisms, MFCs offer a unique method for generating electricity through the oxidation of organic substrates. Recent innovations have enabled the enhancement of MFC performance, such as optimizing microbial consortia, electrode materials, and environmental conditions, to achieve higher energy outputs and Coulombic efficiency. In addition to their application in energy production, MFCs are increasingly recognized for their role in addressing wastewater treatment challenges, effectively degrading organic compounds and reducing the environmental footprint of industrial effluents. Furthermore, MFCs can be adapted to produce biohydrogen, a valuable alternative fuel, by utilizing electrochemical processes that overcome thermodynamic barriers. The integration of MFCs into bioenergy systems represents a transformative approach, utilizing organic waste as a resource for both energy generation and environmental remediation. These advancements underscore the potential of MFCs in contributing to the global transition towards sustainable energy solutions, offering a versatile and eco-friendly alternative to traditional power generation methods.
Keywords: Biohydrogen, Biomass conversion, Microbial fuel cells (MFCs), Wastewater treatment, Renewable energy.
Co-author/s:
Mohammad Reza Rahimpour, Professor of Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Fatemeh Haghighatjoo, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Eng. Maryam Koohi-Saadi, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Keywords: Biohydrogen, Biomass conversion, Microbial fuel cells (MFCs), Wastewater treatment, Renewable energy.
Co-author/s:
Mohammad Reza Rahimpour, Professor of Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Fatemeh Haghighatjoo, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
Eng. Maryam Koohi-Saadi, Researcher in Chemical Engineering, Department of Chemical Engineering, Shiraz University.
