Research On Nickel-based Catalyst Of Synthesising Propionic Acid And Ethyl Propanoate By Vapor Phase Carbonylation Of Ethanol

As an important fine chemical product, propionic acid is well known as one of the mosteconomical, effective, and safest food preservative, which is extensively applied in organicsynthesis, spice, pesticides, feedstuff, coating, printing ink, medical intermediate, antisepsisand preservation for food and corn. The vpaor-phase carbonylation of ethanol to propionicacid and ethyl propionate under atmospheric pressure was investigated, combining theperformance of the catalyst evaluation and characterization of its physical and chemicalproperties, the preparation of the catalysts and reaction process were optimized.Combining characterization of N2physical adsorption, SEM, H2-TPR and XRD, thephysical properties and surface chemical properties of different activated carbon supportmaterials were analysised. The results showed that wood charcoal had an amount of mesoporestructure, higher surface area, more oxygen-containing functional groups and The appropriatesupport adsorption capacity. These factors were conducived to the dispersion of activecomponents Ni on catalyst Ni/CA. Ethanol conversion rate and product selectivity were thehighest,64.32%and56.58%, respectively.The result of surface modification for activated carbon indicated that activity of catalystNi/CH5by5mol/L acid modification was optimal. Ultrasonic treatment was good fordispersion of active components in the process of impregnation to improve the activity ofcatalyst. In order to improve the catalyst performance the second active component Cu wereintroduced. The results showed that activity of catalyst10%Ni-3%Cu/CH5was optimal.When calcination temperature was400℃in the beginning2hours, and reduction temperaturewas450℃in the next2hours, the activity of catalyst was the highest.Reaction process conditions of ethanol carbonylation were investigated，the optimumreaction conditions were also examined: reaction temperature:250℃; the space velocity ofethanol:1.3mL/(gCat h); n(CO):n(EtOH):n(EtI)=10:5:1(mol). Under a forementionedconditions, ethanol conversion of82.97%，and carbonylation selectivity of68.54%wereobtained. The results of study of the stability of the catalyst showed that the catalyst achievedhigher activity after the induction period of2hours, in the study period, the catalyst activitytends to be stable.