5-ethoxymethylfurfural Production From Sugary Food Waste

A large number of food wastes was producted with the development of urbanization and the rapid growth of population.At present,it is mainly treated by incineration and landfill.Which not only cause waste of resources,but also cause environmental pollution.At the same time,the rapid development of urbanization and industrialization has resulted in the depletion of fossil resources,the supply situation of fuel is becoming increasingly severe.And the combustion of fossil energy is usually accompanied by the deterioration of the ecological environment.Therefore,people should search green renewable energy to replace fossil fuels.Biomass,as the most abundant renewable resource has attracted great attention by scholars in the production of fuel and chemicals.5-ethoxymethylfurfural?EMF?,due to its high energy density,and as fuel additives can result in a significant reduction of vehicle soot and SOX emission,so it is recognized as an excellent substitute for diesel fuel.Sugary food waste were used as raw material for EMF production,which not only achieve resource utilization of food waste,but also effectively solve the energy crisis and prevent environmental pollution.This dissertation mainly contains three sections as follow:?1?Fructose was used as a model compound to produce EMF in homogeneous reaction system catalysed by Bronsted acid trifluoromethanesulfonic acid and Lewis acid Cr Cl₃·6H₂O,respectively.The effects of reaction time,reaction temperature,solvent type and dosage on the yield of EMF were investigated.Sugary food waste?expired probiotics solid drinks,brown sugar,honey,onion powder and garlic powder?were used as substrates.When using trifluoromethanesulfonic acid as catalyst for converting sugary food wastes in 10 vol.% DMSO/ethanol at 130? for 15 min,the yields of EMF were 68.3%,37.7%,42.5%,64.9% and 31.3% from expired probiotics solid drinks,brown sugar,honey,onion powder and garlic powder,respectively.When Cr Cl₃·6H₂O was used as catalyst in ethanol at 130? for 50 min,the yields of EMF were 31.5%,25.6%,30.7%,26.1%,23.9%,from expired probiotics solid drinks,brown sugar,honey,onion powder and garlic powder,respectively.When the reaction time was prolonged to 70 min,EMF yields were increased to 33% and 38.7% from expired probiotics solid drinks and honey.?2?Food waste derived carbonaceous solid acid?FW-SO3H?was prepared successfully by hydrothermal carbonization and sulfonation,and was characterized by SEM,XRD,FTIR,XPS,TG,nitrogen physisorption measurements,elemental analysis and acid-base titration.The results showed that the catalyst FW-SO3 H has a good stability,a larger specific surface area and a higher acid density.The as-prepared FW-SO3 H was then used for the acid-catalyzed conversion of fructose into EMF to optimum reaction conditions.EMF yield of 54.2% was obtained in DMSO/ethanol at 140? in 4 h,and affording EMF yields of 52.1%,28.3% and 34.4% from expired probiotics solid drinks,brown sugar and honey,respectively in 12.5vol.% DMSO/ethanol after 4 h at 140?.When expired onion powder and garlic powder were used as substrates in 12.5vol.% DMSO/ethanol at 140? for 10 h,the EMF yields were 9.1% and 4.6%,respectively.?3?A metal organic frame material?MOF?Cr?-SO3H?which contains both Lewis acid site and Bronsted acid site,was prepared by hydrothermal.And it was characterized by SEM,XRD,FTIR,TG and nitrogen physisorption measurements.The results showed that the catalyst MOF?Cr?-SO3 H has a good crystal structure and stability.It was used to catalyze the conversion of fructose,glucose and sugary food wastes to EMF.The weak Bronsted acid property of MOF?Cr?-SO3 H and its space limitations lead to poor EMF yields in the transformation of fructose and sugary food wastes into EMF.However,the production of EMF from glucose by “one-pot” approach can be achieved by using MOF?Cr?-SO3 H due to the synergy of Lewis acid sites and Bronsted acid sites on the catalyst surface.The EMF yield of 23.1% was obtained from glucose in 5 vol.% H₂O/ethanol at 140? for 22 h.