Research On The Conversion Of Fructose To 5-hydroxymethylfurfural By Solid Acid Catalyst

Many of the problems brought about by energy depletion and environmental pollution are ubiquitous in our life.These serious problems not only threaten our lives but also endanger human health.Therefore,the development and utilization of green and renewable resources has become a major issue in our country and that is also conducive to the implementation of the strategy of sustainable development.In recent years,the exploration of biomass has been extensively valued by domestic and foreign researchers.Many studies have shown that the sources of biomass are renewable and also easy to use.Biomass energy provide great potential for the study of alternative energy sources.Therefore,biomass resources,which are closely related to our lives,also provide us with opportunities for development.That is biomass resources can be converted into5-hydroxymethylfurfural?5-HMF?,an important raw material for fuels and chemicals.Solid acid catalyzes the conversion of fructose to 5-HMF under the optimal conditions.The solid acid catalyst used in the reaction is firstly produced by laboratory UIO-66 as the precursor.Since the different calcination temperature has a great influence on the crystal structure of the calcined product ZrO₂,the product is obtained according to the different calcination temperature.PXRD analytical skill can be found that we can obtain the crystal structure of tetragonal phase ZrO₂ in the 500 ? roasting 24 h conditions,and then the tetragonal ZrO₂ can be seen as the catalyst carrier,while using 0.5mol/L,1mol/L and 2mol/L sulfuric acid solution immerse the certain ZrO₂ for 24 h respectively.The results show that the sulfur content of the catalyst was 14% using 1mol/L sulfuric acid solution and the thermal stability was better by the method of TG and ICP.Finally,we prepared the solid superacid SO₄^2-/ZrO₂ and series of characterizations have been done.The results show that the solid acid catalyst prepared by us has not only high sulfur content,good thermal stability,but also uniform crystal structure,and has strong acid strength and acid sites.After the preparation of the catalyst,we used this catalyst for the conversion of fructose to 5-HMF.In this reaction system,we investigated the effects of temperature,time and the mass of the catalyst on the reaction in solvothermal synthesis method,while dimethyl sulfoxide as the solvent.The conversion of reactants and yield of products were determined by high performance liquid chromatography?HPLC?.The conversion of fructose was 100%,and the yield of 5-HMF could reach 90% when the mass of fructose was 150 mg,solvent DMSO was 7ml,catalyst dosage was 50 mg and temperature was130?,time was 2h.In order to investigate the repeatability and reproducibility of the catalyst,we used thebest reaction conditions for six replicative experiments to give an average yield of 85%.The used catalyst still had a good catalytic activity after the regeneration process,and the PXRD pattern shows that the crystal structure of the regenerated catalyst is almost unchanged compared to the original catalyst.