Process for synthesizing DM through pure oxygen oxidation

Abstract

The invention belongs to the field of chemical industry and in particular relates to a process for synthesizing DM through pure oxygen oxidation. The process comprises the following steps: adding an M sodium salt into a reaction kettle capable of realizing stirring by a stainless steel band, adding water, controlling the concentration of the sodium salt to be 5-6 percent, adding sulfuric acid, regulating the pH value to be 9.8-10.2, starting stirring, heating to 60-70 DEG C, dripping a mixed solution of sulfuric acid and hydrogen peroxide, and stopping dripping the mixed solution of sulfuric acid and hydrogen peroxide when the pH value is 8; and introducing pure oxygen for oxidizing, testing the reaction solution by using a special agent for cobalt oleate when the pH value is 7, determining the end point when the agent is turned into red, stopping introducing the pure oxygen, continuously stirring for 20 minutes, stopping stirring, standing for 30 minutes, washing with water, centrifuging, dehydrating, and drying, thereby obtaining the product. An oxidation synthetic process of the hydrogen peroxide and pure oxygen is adopted, the obtained product is light white in appearance and stable in quality, the yield is over 99.5 percent, and the melting point is higher than 170 DEG C.

Description

Technical field [0001] The invention belongs to the field of chemical industry, and specifically relates to a process for synthesizing DM by pure oxygen oxidation. Background technique [0002] Vulcanization accelerator DM, scientific name dibenzothiazole disulfide, is a kind of thiazole rubber vulcanization accelerator with excellent performance, mainly used in the manufacture of tires, hoses, rubber pads, tarpaulins, bright colored rubber products, hoses, Industrial rubber products for non-food applications such as wires, cables, and rubber shoes. Compared with other accelerators such as thiurams, guanidines, disulfide carbamates, and sulfenphthalamides, thiazole vulcanization accelerators have fast vulcanization, flat vulcanization curve, good physical properties, safe and reliable operation Features: Among the thiazole accelerators, because the accelerator DM has two promoting groups and one anti-scorching group, it has the advantages of long scorch time and low toxicity. I...

AI Technical Summary

Problems solved by technology

Compared with the previous two production methods, this production method has reduced toxicity of the reagents used, and adopts simpler process equipment, convenient operation and safe production; but in the production process, high-concentration sodium chloride wastewater will be produced, causing Serious "three wastes" pollution, contrary to the advocated green chemistry

The fourth type: the commonly used method of using oxygen as an oxidant to catalyze the oxidation of M to produce DM; compared with the first three production methods, the raw material M can be used for production without purification, which obviously saves time and energy, and the by-product With only water, the whole process is convenient and safe to operate; however, in the production process, ammonium salt wastewater will be generated, which consumes a lot of energy for recycling, thus causing serious pollution of "three wastes"; and salt-forming treatment is required before M oxidation, which makes the process cumbersome

The fifth type: hydrogen peroxide as an oxidant, which is expensive and troublesome to operate

Using this method can effectively improve product quality, save energy and reduce consumption, and reduce "three wastes" pollution, but the operation is complicated