Biomass Conversion to Fuels and Value-Added Chemicals: A Comprehensive Review of the Thermochemical Processes

Abstract

Aims: This paper reviews extensively the thermochemical processing of biomass to fuels and high-value chemicals, with more emphasis on the process performance, conditions, and weaknesses. The important chemical compositions of biomass feedstock, their conversion technologies and most importantly, the role of catalysis in their conversion to fuels, fuel additives, based chemicals, and added-value chemicals are also discussed. Background: Fossil fuels have fueled the world economy for decades. However, given their unlimited nature, fluctuating prices and the escalating environmental concerns, there is the urgent need to develop and valorize cheaper, cleaner and sustainable alternative energy sources to curb these challenges. Biomass represents a valid alternative to fossil fuels, especially for fuel and chemical production as it represents the only natural organic renewable resource with vast abundance. A vast array of conversion technologies is used to process biomass from one form to another, to release energy, high-value products or chemical intermediates. Objective: To extensively review the thermochemical processing of biomass to fuels and high-value chemicals, and to discuss important chemical compositions of biomass feedstock, their conversion technologies and most importantly, the role of catalysis in their conversion to fuels, fuel additives, based chemicals, and added-value chemicals. Method: Extensive review and analysis of prominent scientific papers in bioenergy Result: Biomass has a huge potential for climate change mitigations and almost all fossil-derived fuels and chemicals are obtainable from biomass using appropriate processing techniques Conclusion: There is a huge prospect for fuel and chemical production from biomass, as it is a very rich source of solid, liquid and gaseous fuels and high-value chemicals or high-density energy and chemical precursors. Other: Biomass processing to fuels and chemicals has promising future prospects for sustainable large-scale biomass processing, especially in the modern biorefinery.

A Review of Hydrothermal Biomass Liquefaction: Operating Parameters, Reaction Mechanism, and Bio-Oil Yields and Compositions

“…98 The carboxylic acids in bio-oil include acetic acid, propionic acid, valeric acid, caproic acid, etc., and their content is usually 10%−30%. 99 The ester compounds in bio-oil include methyl formate, methyl acetate, methyl butyrate, etc., which are usually compounds generated by the reaction of carboxylic acid and alcohol. And their content can reach about 20%−50%.…”

“…Bio-oil is a complex mixture that typically contains a wide range of organic compounds (Figure ), including carboxylic acids, esters, alcohols, phenols, ketones, ethers, aldehydes and aromatic hydrocarbons . The carboxylic acids in bio-oil include acetic acid, propionic acid, valeric acid, caproic acid, etc., and their content is usually 10%–30% . The ester compounds in bio-oil include methyl formate, methyl acetate, methyl butyrate, etc., which are usually compounds generated by the reaction of carboxylic acid and alcohol.…”

Agricultural Waste-Based Heterogeneous Catalyst for the Production of Biodiesel: A Ranking Study via the VIKOR Method

“…Besides electricity, fuel is the most significant energy source to run modern-day society, and fossil fuels are providing most of the energy demand [1]. Out of the total global energy consumption, 81% is associated with fuel, and 90% of the need is being fulfilled by fossil resources [1,2]. With regard to the total worldwide energy consumption, 54% is being spent in the transport sector with an increased average rate of 1.1% yearly, and by 2050, the total energy consumption of the world is estimated to reach 57% [3].…”

Effect of pretreatment parameters and binder concentration on the densification of wood residue

“…Wood residues also require pretreatment such as lime treatment (further detail in Section 2.1.4) for their optimal applications 23 . Pretreatment regulated the thermochemical conversion of biomass and changed their structural properties and energy utilization efficiency 24,25 . Physical or chemical pretreatment methods are the most commonly used methods for wood residues which involve the use of organic or inorganic compounds to disrupt their structure 26 .…”

“…23 Pretreatment regulated the thermochemical conversion of biomass and changed their structural properties and energy utilization efficiency. 24,25 Physical or chemical pretreatment methods are the most commonly used methods for wood residues which involve the use of organic or inorganic compounds to disrupt their structure. 26 It causes the lignin to split up for releasing the cellulose and hemicellulose from the lignocellulosic structure.…”