| Cellulose has a very important position in the field of catalytic biomass conversion because of its rich content in nature and inedible.Because of the structure,the transformation of cellulose to glucose is the first step.System that is capable of catalyzing the conversion of glucose into other platform chemicals is one of the most atom-economic pathways for converting cellulose.We prepare glucaric acid by oxidation of glucose and then hydrogenolysis glucaric acid to adipic acid,which is one of the most important chemical materials.Here,we report this very cost-effective synthetic method.We found that the Pt/CNT is effective for the conversion of glucose and a-methyl glucoside.Under 1 MPa oxygen atmosphere,333 K,with appropriate amount of base,the yield of glucaric acid can reach to 81%after 4 h reaction.The studies on reaction pathways suggest that glucose is firstly oxidated to gluconic acid,and the H+ from gluconic acid auto catalyse the aldehyde group in glucose and glucuronic acid go to retro-aldol reaction.And in acidic environment,the product of glucaric acid is unstable,which easily broke the C-C bond and over oxidation.So we control the pH of reaction condition to get the glucaric acid.The study of reaction conditions shows that high temperature will also increase the by-product.The oxidation of a-methyl glucoside is also investigated in this thesis.We use Pt/CNT as catalyst and H2O2 as oxidant,add NaHCO3 to control the reaction pH,after 3 h under 333 K reaction,the yield of a-methyl glucoside acid can reach to 80%.But further transformation of a-methyl glucoside acid in acid,we found glucuronic acid is unstable and quickly converted to by-products in water. |
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