Bio-Solvents: Synthesis, Industrial Production and Applications

Abstract

Solvents are at the heart of many research and industrial chemical processes and consumer product formulations, yet an overwhelming number are derived from fossils. This is despite societal and legislative push that more products be produced from carbon-neutral resources, so as to reduce our carbon footprint and environmental impact. Biomass is a promising renewable alternative resource for producing bio-solvents, and this review focuses on their extraction and synthesis on a laboratory and large scale. Starch, lignocellulose, plant oils, animal fats and proteins have been combined with creative synthetic pathways, novel technologies and processes to afford known or new bio-derived solvents including acids, alkanes, aromatics, ionic liquids (ILs), furans, esters, ethers, liquid polymers and deep eutectic solvents (DESs)-all with unique physiochemical properties that warrant their use as solvation agents in manufacturing, pharmaceutical, cosmetics, chemicals, energy, food and beverage industries, etc. Selected bio-solvents, conversion technologies and processes operating at commercial and demonstration scale including (1) Solvay's Augeo™ SL 191 renewable solvent, (2) Circa Group's Furacell™ technology and process for making levoglucosenone (LGO) to produce dihydrolevoglucosenone (marketed as Cyrene™), (3) Sappi's Xylex ® technology and demonstration scale processes that aim to manufacture precursors for biosolvents and (4) Anellotech's Bio-TCat™ technology and process for producing benzene, toluene and xylenes (BTX) are highlighted.

SOLVENTS: From Past to Present

“…Toward the goals of ensuring alignment with Green Chemistry Principles, aiming to minimize environmental impact and health hazards associated with traditional solvents and increased recyclability of solvents postreaction, a range of alternatives have emerged in recent decades. Biobased Solvents: Derived from renewable resources such as plants, vegetable oils, or biomass, biobased solvents offer a sustainable alternative in terms of fossil carbon source avoidance. For example, ethyl lactate, derived from corn, has gained attention for its low toxicity and biodegradability Ionic Liquids: Ionic liquids (ILs) have begun to reach mainstream use as green solvents due to their low volatility and wide temperature range in the liquid state.…”

“…Biobased Solvents: Derived from renewable resources such as plants, vegetable oils, or biomass, biobased solvents offer a sustainable alternative in terms of fossil carbon source avoidance. For example, ethyl lactate, derived from corn, has gained attention for its low toxicity and biodegradability …”

Total synthesis of insect sex pheromones: recent improvements based on iron-mediated cross-coupling chemistry

“…A similar procedure involving sodium alkoxide additives and NHCs was also described by Duong for the aryl–aryl cross coupling [ 29 ]. Alkoxide salts appear as good alternatives to NMP or phosphate-based additives, since several classic alcohol sources display low toxicities and can also come from renewable resources [ 30 ].…”

Sustainable Use of Apple Pomace (AP) in Different Industrial Sectors

“…They rely on the utilization of alternative (green) solvents, eliminating the amount of synthetic and/or petroleum-based chemicals, and reducing energy costs and waste generation to obtain high-quality plant extracts [ 68 ]. Among green solvents, bioethanol is the most often used one due to its high biodegradability and low price [ 69 ]. Water, which is known to be the most natural solvent on the Earth, is effective only for the extraction of polar compounds [ 70 ].…”