|
Glycol ethers are important derivatives of ethylene oxide is an excellent solvent and cleaning agent, widely used in coatings, paints, inks, resins and other industrial fields. Industrially, usually ethylene oxide and alcohols (methanol, ethanol, butanol) as raw materials in the role of catalyst synthesis of ethylene glycol ethers. This is a special kind of reaction (ethoxylation reaction), with a strong exothermic characteristics, while reaction of ethylene oxide activity is very strong, explosive, easily biodegradable, plant safety requirements are very high. In order to develop a new type of green energy production technologies ethylene glycol monomethyl ether, we propose and carry out continuous catalytic distillation synthesis of the product of new technology. In order to understand the technical feasibility and the establishment of the kinetic equation, this paper carried out a semi-batch tank reactor (catalyst primary feeding raw alcohol, ethylene oxide continuous feed) ethylene glycol monomethyl ether synthesis of the research work. Through research, aimed at the development of new technology catalytic distillation lay an important basis for the work. The main research contents, methods used and results obtained the following conclusions: one, to carry out a process of low-carbon alcohol ethoxylate experimental study to determine the optimum process conditions in 2L semi-batch reactor, experiment investigated through process stirring speed, amount of catalyst (representing the mass ratio of the starting alcohol), alkoxy alcohol feed ratio, reaction temperature and pressure conditions on the selectivity of ethylene glycol monomethyl ether, and the suitable process conditions. Among them, ethylene glycol butyl ether synthesis process suitable operating conditions: 0.2% amount of catalyst, the reaction temperature was 373K, the feed molar ratio of alkyl alcohol 3, the pressure of 0.35MPa. In this operating condition, the selectivity of ethylene glycol monobutyl ether 81.36%. Ethylene glycol methyl ether synthesis process suitable operating conditions: 0.5% amount of catalyst, the reaction temperature was 353K, alkyl alcohol molar feed ratio of 2.5, the pressure is 0.40MPa. In this operating condition, the selectivity of ethylene glycol methyl ether 82.87%. In this study, the process for industrial production data and to provide the necessary basis for theoretical guidance. Second, to carry out the synthesis of novel solid base catalyst ethylene glycol monomethyl ether, kinetic studies, the establishment of a kinetic equation first, 2L semi-batch reactor kinetic data were determined through experiments. Secondly, based on each step of the addition reaction mechanism and the assumption of equal reaction rate established kinetic model. Again, the establishment of ethylene oxide concentration in the liquid phase in the calculation of the body, using this method, the concentration of ethylene oxide by the reaction vessel temperature, pressure, amount of added ethylene oxide, nitrogen partial pressure of the autoclave and the reaction mixture composed of the starting agent estimated directly. Regression of experimental data obtained ethoxylated butanol and methanol reaction kinetics equation. Among them, n-butyl alcohol ethoxylate activation energy E = 73061 J · mol-1, pre-exponential factor A = 7.232 × 10 ~ 6 m ~ 3 · mol-1 · s-1; ethoxylation reaction of methanol The activation energy E = 60161J · mol-1, pre-exponential factor A = 5.232 × 10 ~ 7m ~ 3 · mol-1 · s-1. The data obtained in this study for the synthesis of ethylene glycol monomethyl ether, new technology development and amplification to provide basic data and theoretical basis. Third, carry out a commercial scale reactor simulation studies, the establishment of a semi-batch reactor, mathematical models and simulation methods First, according to industrial-scale reactors operating characteristics, the whole process is divided into the reaction of ethylene oxide plus trial stage, Constant phase reaction stage and aging of three parts; secondly, the reaction and the actual reaction mechanism is established ethoxylation mathematical model; again, by means of software RBatch Aspen plus module, using three methods kettle series , respectively, to simulate the three stages, the vapor of ethylene oxide to obtain liquid composition, pressure and distribution of product composition with time; Finally, the analog values ??and pilot value, that the obtained and the kinetic equation build a simulation method is reasonable and reliable. In this study, for industrial-scale operation of the reactor to provide modeling support, in order to ensure safe operation of the device to provide theoretical guidance.
|