Synthetic method of N-(n-butyl) thiophosphoric triamide

Abstract

The invention discloses a synthetic method of N-(n-butyl) thiophosphoric triamide (NBPT), comprising the following steps: at a certain temperature, respectively adding n-butyl amine and organic alkaline solution dropwisely to a mixed solution of thiophosphoryl chloride and organic solvent; after the reaction, separating water phase, at the constant temperature, introducing ammonia gas into the organic phase, after detection reaction, filtering to remove the generated ammonium chloride, recovering most solvent from the filtrate, cooling, conducting crystallization, filtering, and drying to obtain a final product of NBPT. According to the invention, by using the organic alkaline solution as an acid binding agent, the disadvantage of complicated recovery of organic alkali is overcome, and inorganic salts can be directly removed after the reaction; the method has the advantages of easy obtainment of raw materials, cheap raw materials, simple operation steps, and high yield and high purity of products, and is suitable for industrial production.

Description

(1) Technical field [0001] The invention relates to a synthesis method of N-n-butylthiophosphoric triamide (NBPT), in particular to a method suitable for industrialization of N-n-butylthiophosphoric triamide. (2) Background technology [0002] For a long time, the low utilization rate of nitrogen fertilizer and the pollution of the environment have been one of the world's focus issues. Urea is the most widely used, largest and most popular fertilizer variety in the world and in my country. However, due to the large amount of application and the low utilization rate of only 30% to 35%, it is necessary to control the reduction of nitrogen loss and the resulting water pollution, soil pollution, and agricultural product pollution caused by the accumulation of ammonia and nitrate in the soil. A series of environmental problems need to be solved urgently. Therefore, improving the efficiency of nitrogen fertilizers to avoid environmental pollution, paying attention to the release...

AI Technical Summary

Problems solved by technology

The use of triethylamine as an acid-binding agent increases the difficulty of separation and the cumbersome procedures and equipment for recycling triethylamine, while increasing the amount of ammonia used, resulting in a waste of resources in production and a certain degree of damage to the environment. Pollution

Patents represented by WO2010045895, US5955630, US208287709, etc., although the above method is also used to prepare, but no other organic acid-binding agent is added in the reaction process, and part of the alkylamine or ammonia acts as a link between the reactant and the acid-binding agent. The double role increases the amount of raw materials used, and there are many by-products, which cause certain difficulties to the separation and purification of the final product. At the same time, the generated alkylamine hydrochloride is treated with lye to recover the alkylamine, which increases the Reaction equipment increases production costs and narrows profit margins, which is not conducive to large-scale industrial production

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