Synthesis of organic polysulfide

Abstract

The invention discloses a synthesis method of an organic polysulfide used as a vulcanizing agent. In this method, the FCC distillate oil rich in olefins is used as a raw material. Under the action of a basic catalyst, the sulfur and the double bonds in the olefins undergo an addition reaction to form an adduct, and the unreacted elemental sulfur is separated by purification to obtain A mixture of relatively pure organic polysulfides. The organic polysulfide is mainly used as a vulcanizing agent for pre-sulfurization outside the hydrogenation catalyst. Its raw material has a wide range of sources and low cost, which can solve the problem of high production cost of the current organic vulcanizing agent; due to the use of mixed olefins as raw materials, the vulcanizing agent During application, the problem of excessively concentrated heat release can be alleviated; the process also has the advantages of simple preparation method and high sulfur content in the product, and has broad application prospects in the presulfurization process outside the hydrogenation catalyst.

Description

Technical field: [0001] The invention relates to an auxiliary agent used in the oil refining field, in particular to a method for synthesizing an organic polysulfide of a hydrogenation catalyst presulfiding agent. Background technique: [0002] Organopolysulfides are generally prepared by reacting mercaptans with elemental sulfur in the presence of basic catalysts. Traditional catalysts are amines, alkanolamines, inorganic bases, mercaptans or alcoholates. The shortcoming of these catalysts is: or yield is not high, or product purity is not enough, or cost is high. Therefore, the improvement of this synthetic route is mainly the research and improvement of the catalyst used. Adopt a kind of general formula in CN87108064A to be RSH x (C m h 2m O) The composition of yMOH is used as a catalyst, wherein R is an alkyl group of C6~C18, x is 4~12, C m h 2m O is a C2-C4 alkylene oxide, M is an alkali metal atom, and y is 0.1-0.5. Using this catalyst to prepare organic polysul...

AI Technical Summary

Problems solved by technology

The disadvantages of these catalysts are: or the yield is not high, or the product purity is not enough, or the cost is high

The sulfurized olefin prepared by this method has low cost and simple process, but the product has high viscosity and poor fluidity, and needs to be diluted with solvent before use.

The additives used are one or more commonly used additives for rubber vulcanization. These additives are very expensive and most of them pollute the environment.

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