Device for preparing polyisobutylene maleic anhydride

Abstract

The invention discloses a micro-positive pressure device for preparing polyisobutylene maleic anhydride. The micro-positive pressure device is characterized by comprising a maleic anhydride pre-storing and conveying system, a polyisobutylene pre-storing and conveying system, an inert gas micro-positive pressure conveying system and a main reaction kettle system. The end of the maleic anhydride feeding pipe is improved to be of an umbrella-shaped spraying structure and matched with the frame type stirrer, liquid maleic anhydride is evenly dispersed in the reactor through the booster pump, and therefore self-agglutination and scorching of maleic anhydride caused by too large instantaneous concentration under the high-temperature condition are reduced. Besides, inert gas is introduced into the main reaction kettle, so that the main reaction kettle is in a micro-positive pressure oxygen-free state, the solubility of maleic anhydride in polyisobutene is effectively improved, and the reaction efficiency is further improved. Compared with the prior art, the device has the advantages that the reaction temperature is reduced, the reaction time is shortened, and the prepared polyisobutylene maleic anhydride has the advantages of light color, high saponification value, no scorch byproduct and the like.

Description

technical field [0001] The invention relates to a micro-positive pressure device for preparing polyisobutylene maleic anhydride, which belongs to the field of chemical devices. Background technique [0002] The succinimide type ashless dispersant is currently the most widely used and most used dispersant. It is mainly composed of three different groups: a hydrocarbon group, a polar group and a linking group. It can be seen from the structure that the hydrocarbon group and the polar group are connected by a linking group, and maleic anhydride is the most commonly used linking group. Polyisobutylene maleic anhydride (PIBSA) is an intermediate product in the preparation of ashless dispersants, and its structure and properties directly determine the success or failure of the subsequent amination reaction. [0003] In the 1960s, Mobil Petroleum Company first disclosed the process of preparing PIBSA by "chlorinated alkylation method" (patent US3960900). Low, but due to the intro...

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Problems solved by technology

[0003] In the 1960s, Mobil Petroleum Company first disclosed the process of preparing PIBSA by "chlorinated alkylation method" (patent US3960900). Low, but due to the introduction of chlorine gas in the production process, in order to prevent chlorine gas from corroding equipment, the reaction vessel is made of special alloy material and the maintenance is cumbersome, which increases the production cost. In addition, the free chlorine content in the product is relatively high, especially when added to fuel as a fuel additive After being burned in medium, it is easy to produce toxic carbon dioxide and other substances

However, the solubility of maleic anhydride in polyisobutylene under normal pressure is only 0.5%, and the two raw materials of polyisobutylene and maleic anhydride are incompatible with each other, so a large amount of maleic anhydride is sublimated from polyisobutylene by heat during the reaction process, and when it comes into contact with After the reaction kettle wall condenses and crystallizes, it undergoes a cycle of vaporization-crystallization-liquefaction-vaporization, causing the vaporized maleic anhydride to adhere to the wall of the agitator or reactor, agglomerating and burning to produce tar-like by-products

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