Catalysis and reaction Laboratory of Xiamen University: one pot synthesis of gluconic acid from l-glucan catalyzed by cesium phosphotungstate supported gold

As an important environment-friendly chelating agent and water-soluble detergent, lead gluconic acid is widely used in food, medicine and paper industry At present, gluconic acid is mainly produced by biological fermentation of glucose, and the raw material glucose is hydrolyzed from edible starch Many researches have been devoted to the preparation of gluconic acid from inedible cellulose Nevertheless, the growing market demand for gluconic acid has prompted researchers to develop more efficient thermal catalysis processes using inedible cellulose or lignocellulose Recently, the catalysis and reaction Laboratory of Xiamen University has made the latest progress in one pot synthesis of gluconic acid (DOI: 10.1039 / c9gc03066b) Based on the collaborative innovation center of energy materials chemistry and National Engineering Laboratory of clean production of alcohol ether ester chemical industry, Xiamen University catalysis and reaction laboratory was founded under the guidance of Professor Wang Yong In 2013, he has been working closely with Professor Xiong Haifeng's research group to study the optimal utilization of carbon resources in combination with catalytic reaction chemistry and chemical reaction engineering Wan Shaolong, associate professor, Department of chemical engineering, School of chemical engineering, Xiamen University In 1997, he graduated from Tianjin University with a bachelor's degree in polymer chemical engineering; in 2000, he graduated from East China University of science and technology with a master's degree in chemical engineering; in 2000-2003, he worked in Shanghai BASF dye Chemical Co., Ltd.; in 2004-2009, he obtained a doctor's degree from the University of Mississippi in the United States, mainly engaged in the research of coal combustion; in 2009-2014, he joined Daniel of the University of Oklahoma in the United States Resasco research group is engaged in the research of biomass catalytic conversion, with rich interdisciplinary research experience and working background The patent device of the small feeder developed during the doctoral period was purchased by Babcock and Wilcox, a famous multinational company The pilot plant of biomass catalytic pyrolysis developed during the postdoctoral period was reported by local media in Oklahoma, USA The independently designed and manufactured pilot plant of continuous feed catalytic pyrolysis was imported by Vietnam petroleum company Since joining the research group in 2014, he has been committed to the research of catalysis in energy and chemical industry His main research fields include the preparation of fuel and high value-added chemicals by catalytic conversion of biomass, efficient catalytic conversion of syngas, hydrogen production by steam reforming of methanol and the development and application of microchannel reactor technology Cutting edge scientific research achievements: one pot synthesis of gluconic acid by catalytic conversion of l-glucan with cesium phosphotungstate supported gold is an efficient and low cost method for large-scale conversion of primary biomass into liquid products, i.e bio oil; however, the products obtained by one-step rapid pyrolysis are complex and difficult to be modified Therefore, the more ideal way is to obtain relatively simple pyrolysis products by means of the staged condensation of biomass pyrolysis gas or multistage thermal cracking under different reaction conditions, and then carry out the catalytic design appropriately for the sake of the substance, and convert them into high value-added chemicals or liquid fuels Brown et al Reported for the first time that high-purity l-glucan aqueous solution can be obtained from biomass pyrolysis gas through stepwise condensation and simple separation process If the bagasse is used as raw material for multistage cracking or stepwise condensation, and it is extracted and filtered by water phase, the solution of up to 23wt% l-glucan can be obtained Therefore, it is of great significance to develop efficient catalytic methods to convert l-glucan which can be obtained from biomass into high value-added chemicals At present, there are few reports on the catalytic conversion of l-glucan, only santhanaraj and others used acid resin amberlyst-15 to hydrolyze l-glucan to get glucose, and then used Pd / C catalyst to catalyze the oxidation of glucose to gluconic acid in alkaline solution Based on this, Wan Shaolong, a team from catalysis and Reaction Engineering Laboratory of Xiamen University, designed and prepared the cesium phosphotungstate supported gold nanoparticles dual functional catalyst, which was used to catalyze the conversion of l-glucan to gluconic acid in one pot in oxygen atmosphere and aqueous solution Figure 1 The effect of reaction temperature on the conversion of l-glucan and the selectivity of various products (source: Green chem.) experimental results show that at 145 ℃, Au / CS 2.5h0.5 PW12O40 catalyst can efficiently convert l-glucan to gluconic acid in aqueous phase In non alkaline environment, the conversion rate can reach 93.6%, the selectivity of gluconic acid can reach 93.1%, and the volume yield can reach 4.0 g / L / h (Figure 1) Figure 2 (a) conversion rate of l-glucan, (b) change of yield of each product to reaction time (source: Green chem.) Figure 3 Catalytic conversion path of l-glucan on Au / CS 2.5h 0.5 PW12O40 catalyst (source: Green chem.) table 1 Reaction rate constant (10-2lg-1h-1) (source: Green chem.) catalytic reaction results and TOS diagram of different substrates (glucose, glyoxylic acid, glycolic acid) under the same reaction conditions The catalytic conversion path of l-glucan was proposed and the reaction rate constants of each reaction step were calculated The results showed that the hydrolysis rate of l-glucan was slow, and the fastest step was the oxidation of glucose to gluconic acid, which was the same as the reaction trend when glucose was used as substrate The reaction rate constant K 3 was significantly higher than K 4, indicating that the by-products were mainly from the decomposition of glucose rather than gluconic acid The corresponding author of the work is wan Shaolong, associate professor of Xiamen University, and the first author is wan Yan, doctor of Xiamen University The research was supported by the National Natural Science Foundation of China (No 91545114, No 91545203, No 21576227) and the 985 project of chemical engineering discipline of Xiamen University Nowadays, people and scientific research have been paid more and more attention in the economic life China has ushered in the "node of science and technology explosion" Behind the progress of science and technology is the work of countless scientists In the field of chemistry, in the context of the pursuit of innovation driven, international cooperation has been strengthened, the influence of Returned Scholars in the field of R & D has become increasingly prominent, and many excellent research groups have emerged in China For this reason, CBG information adopts the 1 + X reporting mechanism CBG information website, chembeangoapp, chembeango official micro blog, CBG information wechat subscription number and other platforms jointly launch the column of "people and scientific research", approach the representative research groups in China, pay attention to their research, listen to their stories, record their demeanor, and explore their scientific research spirit.