Recent research efforts in the area of biotechnology for fuels and chemicals

Applied Biochemistry and Biotechnology -     

Biotechnology for production of fuels,chemicals, and materials from biomass

Applied Biochemistry and Biotechnology - Biological systems can convert renewable resources, including lignocellulosic biomass, starch crops, and carbon dioxide, into fuels, chemicals, and...     

Synthesis gas as substrate for the biological production of fuels and chemicals

Synthesis gas provides a simple substrate for the production of fuels and chemicals. Synthesis gas can be produced via established technologies from a variety of feedstocks including coal, wood, and agricultural and municipal wastes. The gasification is thermally efficient and results in complete conversion of the feedstock to fermentable substrate.Clostridium ljungdahlii grows on the synthesis gas components, carbon monoxide, hydrogen, and carbon dioxide. Production of acetic acid and ethanol accompanies growth with synthesis gas as sole source of energy and carbon. Rate and yield parameters are compared forC. ljungdahlii grown on carbon monoxide, or hydrogen with carbon dioxide.

     

Bioelectronics and biometallocatalysis for production of fuels and chemicals by photosynthetic water splitting

Applied Biochemistry and Biotechnology - By inserting metallocatalysts (such as platinum, osmium, or ruthenium) at the reducing site of photosystem I (PSI), electrons that emerge from PSI can be...     

生产运输燃料和有机化学品生物催化体系的新进展

总结了细菌作为生物催化剂的特征和应用的新进展,预测了未来发展趋势。深入讨论了微藻系统的发展,包括PetroAlgae公司和中国石化石油化工科学研究院微藻实验室的一些进展。     

Lignin depolymerization for phenolic monomers production by sustainable processes

Biomass wastes(almond shell and olive tree pruning) were used in this work as raw materials for the extraction of high purity lignin by different delignification methods. A pretreatment stage was carried out to remove the major hemicelluloses content in the solid feedstocks. Afterward, two sulfur-free pulping processes(soda and organosolv) were applied to extract the largest fraction of lignin. The extracted lignin contained in the liquors was isolated using selective precipitation methods to design a tailor-made technique for obtaining high-purity lignin(in all cases more 90% of purity was reached). Soda process allowed the extraction of more lignin(around 40%–47%) than organosolv process(lower than 20%) regardless of the lignocellulosic source employed.Once the different lignin samples were isolated and characterized, they were depolymerized for the obtaining of small phenolic compounds. Three main streams were produced after the reaction: phenolic enriched oil, residual lignin and coke. After the purification of these fractions, their quantifications and characterization were conducted.The most abundant product of the reaction was residual lignin generated by the undesirable repolymerization of the initial lignin with yields around 30%–45%. The yield of the stream enriched in phenolic oil was higher than 20%. Coke, the lowest added-value product, presented a yield lower than 12% in all the cases. Lignin from organosolv presented higher phenolic oil yields, mainly due to their lower molecular size. This parameter was, thus, considered a key factor to obtain higher yields.     

Selective electrocatalytic conversion of methane to fuels and chemicals

The increase in natural gas reserves makes methane a significant hydrocarbon feedstock. However, the direct catalytic conversion of methane into liquid fuels and useful chemicals remains a great challenge,and many studies have been devoted to this field in the past decades. Electrocatalysis is considered as an important alternative approach for the direct conversion of methane into value-added chemicals, although many other innovative methods have been developed. This review highlights recent advances in electrocatalytic conversion of methane to ethylene and methanol, two important chemicals. The electrocatalytic systems efficient for methane conversions are summarized with an emphasis on catalysts and electrolytes. The effects of reaction conditions such as the temperature and the acid–base property of the reaction medium are also discussed.     

Defective TiO2 for photocatalytic CO2 conversion to fuels and chemicals

Photocatalytic conversion of CO₂ into fuels and valuable chemicals using solar energy is a promising technology to combat climate change and meet the growing energy demand. Extensive effort is going on for the development of a photocatalyst with desirable optical, surface and electronic properties. This review article discusses recent development in the field of photocatalytic CO₂ conversion using defective TiO₂. It specifically focuses on the different synthesis methodologies adapted to generate the defects and their impact on the chemical, optical and surface properties of TiO₂ and, thus, photocatalytic CO₂ conversion. It also encompasses theoretical investigations performed to understand the role of defects in adsorption and activation of CO₂ and identify the mechanistic pathway which governs the formation and selectivity of different products. It is divided into three parts: (i) general mechanism and thermodynamic criteria for defective TiO₂ catalyzed CO₂ conversion, (ii) theoretical investigation on the role of defects in the CO₂ adsorption–activation and mechanism responsible for the formation and selectivity of different products, and (iii) the effect of variation of physicochemical properties of defective TiO₂ synthesized using different methods on the photocatalytic conversion of CO₂. The review also discusses the limitations and the challenges of defective TiO₂ photocatalysts that need to be overcome for the production of sustainable fuel utilizing solar energy.

This review discusses photocatalytic CO₂ conversion using defective TiO₂, with emphasis on the mechanism, the role of defects on CO₂ adsorption–activation and product selectivity, as well as challenges of defective TiO₂ to produce solar fuels.     

Catalytic conversion of lignocellulosic biomass to fine chemicals and fuels

Lignocellulosic biomass is the most abundant and bio-renewable resource with great potential for sustainable production of chemicals and fuels. This critical review provides insights into the state-of the-art accomplishments in the chemocatalytic technologies to generate fuels and value-added chemicals from lignocellulosic biomass, with an emphasis on its major component, cellulose. Catalytic hydrolysis, solvolysis, liquefaction, pyrolysis, gasification, hydrogenolysis and hydrogenation are the major processes presently studied. Regarding catalytic hydrolysis, the acid catalysts cover inorganic or organic acids and various solid acids such as sulfonated carbon, zeolites, heteropolyacids and oxides. Liquefaction and fast pyrolysis of cellulose are primarily conducted over catalysts with proper acidity/basicity. Gasification is typically conducted over supported noble metal catalysts. Reaction conditions, solvents and catalysts are the prime factors that affect the yield and composition of the target products. Most of processes yield a complex mixture, leading to problematic upgrading and separation. An emerging technique is to integrate hydrolysis, liquefaction or pyrolysis with hydrogenation over multifunctional solid catalysts to convert lignocellulosic biomass to value-added fine chemicals and bio-hydrocarbon fuels. And the promising catalysts might be supported transition metal catalysts and zeolite-related materials. There still exist technological barriers that need to be overcome (229 references).     

New research findings in biotechnology for fuels and chemical production

Applied Biochemistry and Biotechnology -     

Introduction to the proceedings of the eleventh symposium on biotechnology for fuels and chemicals

Applied Biochemistry and Biotechnology -     

Introduction to the proceedings of the twenty-eighth symposium on biotechnology for fuels and chemicals

Applied Biochemistry and Biotechnology -     

Introduction to the proceedings of the thirteenth symposium on biotechnology for fuels and chemicals

Applied Biochemistry and Biotechnology -     

Biotechnological progress in producing fuels and valuable chemicals and in bioremediating environmental impacts

Applied Biochemistry and Biotechnology - The 71 poster papers presented at the 16th Symposium on Biotechnology for Fuels and Chemicals provided new information on ethanol production, feedstock...     

Liquid-phase catalytic processing of biomass-derived oxygenated hydrocarbons to fuels and chemicals

Biomass has the potential to serve as a sustainable source of energy and organic carbon for our industrialized society. The focus of this Review is to present an overview of chemical catalytic transformations of biomass-derived oxygenated feedstocks (primarily sugars and sugar-alcohols) in the liquid phase to value-added chemicals and fuels, with specific examples emphasizing the development of catalytic processes based on an understanding of the fundamental reaction chemistry. The key reactions involved in the processing of biomass are hydrolysis, dehydration, isomerization, aldol condensation, reforming, hydrogenation, and oxidation. Further, it is discussed how ideas based on fundamental chemical and catalytic concepts lead to strategies for the control of reaction pathways and process conditions to produce H(2)/CO(2) or H(2)/CO gas mixtures by aqueous-phase reforming, to produce furan compounds by selective dehydration of carbohydrates, and to produce liquid alkanes by the combination of aldol condensation and dehydration/hydrogenation processes.