The Study On The Liquid-phase Oxidation Of Bioethanol Over Cu-containing Spinel Supported Gold Nanoparticles

Abundant and inexpensive biomass resources are the only renewable resources that can replace fossil fuels to access liquid fuels and chemicals. Thus, the efficient conversion and utilization of biomass and its derivatives is the key to the sustainable development of economy and society.it also can reduce the dependence on the fossil resource which is exhausted and polluted seriously. With the rapid development of ethanol technology, bioethanol has accounted for more than 90% of ethanol production worldwide. In addition to being used as bio-fuel, the most promising use of bioethanol is used as the biomass conversion platform molecular to produce the bulk and fine chemicals.The added value products such as acetaldehyde, acetic acid and ethyl acetate can be obtained by the oxidation of bioethanol. In the selective oxidation of ethanol, the molecular oxygen as oxidant is the hot spot of the study. Among the numerous alcohols oxidation catalysts, the gold catalysts displayed higher antioxidant activity and selectivity, and the activity of gold catalyst is closely related to the properties of carrier. Therefore, the study of the structure activity relationship between gold nanoparticles and the carrier in the process of ethanol oxidation is a challenge and opportunity.Inspired by the Au/MgCuCr2O4 catalyst successful application and efficient Au-Cu synergy in gas phase oxidation of ethanol to acetaldehyde. In this work, the catalytic oxidation of bioethanol with Cu spinel supported gold catalyst is proposed, We studied the effect of the composition and structure of Cu containing spinel, the Au-Cu synergistic and catalytic properties. Two series of CuCr and CuFe-spinel supported gold catalysts were prepared for bioethanol liquid phase oxidation and the gold particle size were nm 2-4. The results showed that 1%Au/CuFe2O4 which is roasted in 700? has the optimal performance of the catalytic oxidation of ethanol. In 150?,3.0MPa,24 hours reaction, ethanol conversion reach 88.70% and the selectivity of acetic acid is up to 92.67%. We also compared the catalytic performance of CuFe2O4 spinel with different noble metals Au, Pt, Pd loaded on ethanol liquid phase oxidation. Au/CuFe2O4 is far better than Pt /CuFe2O4 and Pt /CuFe2O4. We investigated the process conditions of Au/CuFe2O4 in liquid-phase bioethanol oxidation. We also explored the effect of reaction temperature, time, gold load, the amount of catalyst, ethanol concentration on conversion of ethanol and product distribution. Finally, we discussed the stability of Au/CuFe2O4, the catalyst can be reused for five times, and the catalytic cativity has decrease slightly.