| The reaction rectification is a new chemical engineering process in which the chemical reaction unit is coupled with rectifying unit through the reaction rectification tower. Compared to traditional chemical engineering process, it offers special advantages, such as high yield special selectivity low energy cost, a few process steps, easy to be automatized etc.,so that it draws intensive attention in chemical engineering research field and enterprises in recent years. Several new reaction rectification techniques have been exploited for replacing traditional chemical engineering process. There is a common feature in those processes developed, i.e. the boiling points of products are far below those of reactants, which favor conducting the reaction rectification technique. It is important to apply the reaction rectification technology improving the synthesis selectivity and controlling chlorination depth,but the boiling points of orgaic chlorides are higher than that of reactants, which makes things difficult to synthesize organic chlorides by the reaction rectification technology. In the present dissertation, the principles and application of the reaction rectification techology in the syntheses of benzyl chloride, chloroacetic acid, monochloroacetone were approached.Benzyl chloride is an important intermediate in the organic synthesis, widely used in the industry of pharmaceutics, dye, pesticide, plastifier, surfactant , auxiliary perfume, cosmetics, sanitizer detergent and food etc.Currently the batch process of chlorination and rectification is mainly applied in the production of benzyl chloride. A few continuous processes of chlorination and still rectification have been found. In the batch process of chlorination, the byproduct -benzyl bichloride comes out when the benzyl chloride content reaches 20%, which causes low single-pass chlorination depth, high consumption of raw materials, much operation cost, and serious contamination to the environment. The reaction rectification technique can solve the conflict between the reactant conversion and the product selectivity. The research related to application of this technique was just launched in the United Sates in recent years.In the present dissertation, benzyl chloride was synthesized from toluene and chloride by the reaction rectification technique under illumination. Firstly according to the mechanism analysis and kinetic data of the reaction, the chlorination is a first order liquid-phase homogeneous reaction. Then the design scheme of the rectification tower has been roughly figured out, the reaction zone and the distill zone was treated respectively, based on the product content as the common variable. In accordance with kinetic calculation results, the reactant conversion in the reaction zone must be less than 14.5% to yield product 98.5% content directly. On the basis of above results, the reaction rectification tower to synthesize benzyl chloride was established. The influence of reflux rate at the top of tower, light density, ratio of feed and discharge, content of water and ferrous iron in the raw materials were investigated. The output of column was also inspected.Chloroacetic acid is a very important intermediate of Pharmaceuticals, dyes, pesticides, cellulose derivatives. Also it is widely used in the organic synthesis. For the ever growing demand of market, the prospect of development and application is bright.Up to day, the batch process of producing chloroacetic acid is still extensively used in our country, by which byproduct dichloroacetic acid comes out while chloroacetic acid beingproduced. Dichloroacetic acid content can reach 12-25% at the end. The rather amount of dichloroacetic acid not only enhances consumption of raw materials, but also increases the cost, with the difficulty to separate it from the product later the quality of products drops. Dichloroacetic acid is of a few uses causing the huge waste of the fund and equipments.To control the dichloroacetic acid coming out and decrease the consumption o...
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