Study On Synthesis Of 6 - Chloro - 2 - Trichloromethylpyridine With Nitrification Inhibitor

Nitrogenous fertilizer plays a very important role in the production of agriculture, but its in-season utilization rate is only about30%, so it becomes the research direction of nitrogenous fertilizer industry about how to improve the utilization rate of nitrogenous fertilizer.6-chloro-2-(trichloromethyl) pyridine is one of the most important nitrification inhibitor, which is also called N-serve, which can improve the in-season utilization rate of nitrogenous fertilizer efficiently, increase the economic and eco-environment protection benefits. The current production of6-chloro-2-(trichloromethyl) pyridine in our country still have several main problems, such as easy coking, small production scale, difficulty and so on, so the production process to carry out the has important practical significance. Thesis topic is based6-chloro-2-(trichloromethyl) pyridine from Nantong Acetic Acid Chemical Co.Ltd, and solves the current domestic6-chloro-2-(trichloromethyl) pyridine problems existing in the actual production of research, related research results are as follows:Firstly, the article takes a research of way that can put2-methylpyridine as raw material to chlorination synthesize6-chloro-2-(trichloromethyl) pyridine under certain condition, takes a trial ways of the light chlorinated way and conventional heat chlorinated way, light chlorinated way is easy coking, has more by-products and no suitable solvent; while regular heat chlorinated way will cause little products only under very higher ratio of solvent, which is also easy to coking. The main reason that caused the coking is part of high temperature in the reaction system.Secondly, this article make some improvement based on regular light chlorinated way and heat chlorinated way of6-chloro-2-(trichloromethyl) pyridine, this method is mainly changed the way of2-methylpyridine charging,2-methylpyridine by O-dichlorobenzene evently diluted, the diluent and chlorine slowly join in the reaction system at the same time, this method is called improved chlorinated way. It will avoid the coking, it also has mild reaction conditions, fewer steps, simple operations and other advantages.Thirdly, this article optimizes the improved methods for chlorination synthesis of6-chloro-2-(trichloromethyl) pyridine and got the better synthetic route. Under following conditions:the2-methylpyridine and total O-dichlorobenzene mass ratio of1:8;2-methylpyridine and o-dichlorobenzene mass ratio of1:5in titrating solution; Dropping speed of2-methylpyridine solution is controlled to lOg/h; Maintain the temperature of dropping2-methyl pyridine solution same to O-dichlorobenzene reflow; Reaction temperature does not exceed180℃; Chlorine gas flow:80ml/min; Reaction time:48h; Stirring speed:250r/min, to synthesize and separate products (production rate is63.4%, the content is over98%).Finally, this article takes the production process as a point to analyse the scale, design the production process, treat "Three wastes" and analysis the risk of6-chloro-2-(trichloromethyl) pyridine. The above research findings can provide very important reference data for the production of6-chloro-2-(trichloromethyl) pyridine industry.