The Study Of The Solvent Effect On The Catalytic Hydrogenation Of Model Compounds Of Biomass Pyrolysis Oil

Bioenergy has gained wide attention in recent years for its renewable and sustainable natures and is expected to replace fossil energy in the next few years.Pyrolysis oil is a kind of oil-like liquid products,obtained by pyrolysis of biomass.However,several disadvantages of pyrolysis oil,including poor heat stability,strong acidity and corrosivity as well as high oxygen content and high water content,limit its direct use.Therefore,upgrading process is necessary for pyrolysis oil.Noticeably,among many upgrading methods,catalytic hydrogenation has been widely investigated.Generally,in the catalytic hydrogenation process,solvent have great effects on the catalytic efficiency.In the research,furfural,guaiacol were selected as model compounds,the effects of solvent on the to explore catalytic hydrogenation process were studied carefully and the detailed reaction mechanism of the compounds were investigated.Furfural,generally considered as the representative compound of cellulose products in pyrolysis oil.In the research,noble catalyst Ru/C was used as the catalyst,mixture solvents with different water/ethanol volume ratios were used as the reaction media,the effects of water on catalytic hydrogenation process of furfural were explored.Based on the experimental results,it can be conclude that the detailed reaction types were closely related to the water contents in the mixed solvents.Especially,when water was used as the solvent,serious polymerization was observed and the catalyst was deactivated.Accordingly,a competing reaction mechanism was proposed on the basis of the results.Guaiacol,generally was considered as the representative compound of lignin products in pyrolysis oil.The catalytic hydrogenation experiments of furfural were proceeded under the same experimental conditions.The results showed that the guaiacol conversions and the yields of products varied with the water contents in the mixed solvents,while the reaction types were unchanged.When water used as the solvent medium,polymerization did not occur,contrarily,water efficiently promoted the conversion of guaiacol.In order to further explore the effects of solvent properties on guaiacol catalytic transformation processes,seven different compounds were used as the reaction solvents.It shown that guaiacol conversion efficiencies were different in a variety of solvent conditions.FT-IR characterization results showed that there was a relationship between guaiacol catalytic efficiency and the interaction between guaiacol and the used solvents.The experimental conclusions herein are useful for the development of catalytic hydrogenation process of pyrolysis oil.