The Technical Study Of Synthesis Of Diethyl Carbonate From Ethanol And CO₂

With the consumption of fossil fuels,the synthesis of traditional fuel additives is facing many problems,because traditional fuel additives are always based on petrochemical industry,resulting in environmental pollution and greenhouse effect.Therefore,it is necessary to find potential alternatives with completely renewable resources to synthesize bio-based fuel additives.The utilization of carbon dioxide has become a hot topic in recent years.Therefore,this paper has made a series of studies on the synthesis of fuel additive diethyl carbonate from ethanol and carbon dioxide,and optimized the experiment in various aspects.CexZr1-xO2 has excellent catalytic activity for the direct synthesis of diethyl carbonate from ethanol and CO2 at x=0.2.Through the optimization of the preparation,the results show that the catalyst has the best catalytic activity when the titration temperature is 40?,the precipitation environment pH value is 9,and the calcination temperature of the catalyst is 700?.Diethyl carbonate of 4.25 mg/ml can be obtained under gas pressure of 4.5 MPa and ethanol dosage of 10 mL,0.5 g catalyst,reaction temperature of 150? and reaction time of 3 h.The selectivity of catalyst can reach 87%,accompanied by the formation of trace by-product acetaldehyde.The addition of different dehydrating agents has different effects on the synthesis of diethyl carbonate,and the addition of molecular sieves is beneficial to the synthesis of diethyl carbonate.Synthesis of diethyl carbonate.The reuse rate of the catalyst is relatively good,and it can be reused for about 3 times.Pervaporation membrane has a remarkable effect on the separation of products.Pervaporation time was about 1.5 h,the temperature concentration of feed and liquid can reach a stable level,the total flux was 20-140 g/(m2 h),and the separation factor was 75-110.