Hydrotreating of wheat straw in toluene and ethanol

• Wheat straw was hydroliquefied at 300 °C temperature in autoclave in the presence of ethanol or toluene.
• The main compound of the obtained oil is tetrahydrofuran-2-methanol.
• The catalyst has a great influence on the experimentally obtained yield of the product.

In the present work, wheat straw was hydroliquefied at a temperature of 300 °C for 4 h in ethanol or toluene in order to obtain bio-components which are useful for fuel purposes. The experiments were performed in a 100 mL batch reactor under hydrogen pressure of 70 bar. Typically, 2 g of straw and 0.1 g of catalyst (66%Ni/SiO2–Al2O3) were dispersed in 15 g of solvent. The main compounds of the oil produced during the liquefaction of hemicellulose, cellulose and lignin of wheat straw in both solvents are: tetrahydrofuran-2-methanol, 1,2-butanediol and butyrolactone. Besides the mentioned compounds, ethanol favoured the decomposition of bigger molecules to short-chain alcohols such as 1-butanol, 1,2-propanediol and 1,2-ethanediol. Toluene contributes to the production of furans and other cyclic compounds. The light fractions distilled together with the solvent also contain the following: 1-propanol, 2-methyl-cyclopentanone, acetic acid and ethyl acetate.