Vapor-liquid-equilibrium (VLE) at normal pressure for the system formed by n-heptane, benzene and N-methyl-pyrrolidone (NMP) are investigated. The results show that NMP is a good extractive solvent that reverses the volatility of the binary system of n-heptane + benzene. A UNIFAC model is selected and proved that the group interaction parameters are reliable. A modified extractive distillation (MED) process, in which a little of water is added to lower the boiling point of reboilers in aromatics recovery column, is proposed on the basis of the original extractive distillation (OED) process. The process simulation shows that the proposed process raises the yield ratio of benzene from 94.2% to 98.2%. Since the modification is not complicated, the MED process have a lasting value in industry.

A new separation method of reactive extractive distillation is proposed for the separation of isopropanol and water, using the mixture of ethylene glycol (C2H6O2) and glycollic potassium (C2H5O2K) as an entrainer. Vapor-liquid-equilibrium (VLE) measurements confirmed that the entrainer was effective for this separation. Using a feed/solvent volume ratio of 1:1, isopropanol with a concentration over 96.0% weight fraction was obtained by the reactive extractive distillation process and the azeotropic point was eliminated. A novel process of separating isopropanol and water is designed on the basis of reactive extractive distillation to obtain the product with different concentrations, which may have a lasting value in industry.

The prepared catalyst of tungstophosphoric acid supported on SiO2 has shown high activity, good selectivity of producing linear alkylbenzene (LAB) and 2-phenyl isomer and sufficient catalytic stability. Kinetics of benzene alkylation with 1-dodecene over this catalyst was investigated in a fixed-bed reactor after eliminating the influence of internal and external transport. Rate models of formation of different isomers of LAB were derived based on some simplifying assumptions. Kinetic parameters were determined.

eration performance of n-butane selective oxidation to maleic anhydride over a VPO catalyst in fixed-bed reactors was investigated. A temperature-programmed oxidation experiment demonstrated that reoxidation sufficient to activate the catalyst could only be carried out at a temperature higher than that of butane oxidation step. A periodic operation scheme, simultaneous modulation of both composition and temperature, was proposed and examined in a fixed-bed microreactor filled with 0.6 g of crushed catalyst and in a tubular fixed-bed reactor packed with 30 g of catalyst. In both reactors, feed composition modulation enhanced selectivity to maleic anhydride, but the conversion of butane and the yield of maleic anhydride dropped. With a 1:0.4 cycle split and period of 4min, reoxidation of the catalyst at 530℃, and selective oxidation at 405℃, the yield of maleic anhydride by both composition and temperature modulation was improved by 11.4% over that obtained for operation under steady-state conditions with the same time-average flow of n-butane, which indicated that the higher reoxidation temperature was effective in improving reactor performance.

Linear alkylation (LAB) is an important intermediate in the detergent industry. This work deals with the suspension catalytic distillation (SCD) column used for synthesis of C12 alkylbenzene with benzene and 1-dodecene.Anovel solid catalyst, which is friendly to environment, was selected. The kinetic equations using this catalyst were measured in a fixed-bed reactor. The mathematical models of equilibrium (EQ) stage and nonequilibrium (NEQ) stage for alkylation of benzene and 1-dodecene were, respectively, established by incorporating the kinetic equations to simulate the SCD column. By comparison of the results from experiments, it was concluded that the NEQ stage model was more accurate than the EQ stage model for the simulation.