A method for preparing odorless isododecane

Abstract

The present invention relates to a method for preparing odorless isododecane. The isobutene trimer (TIB) reacts with hydrogen in the hydrogenation reactor to prepare crude isododecane, which is dehydrated and dried, and then enters the first-stage deodorization adsorption tower and protects the deodorization tower to obtain the finished product. Structure dodecane. The first-stage deodorization tower can be switched in parallel. The deodorization adsorbent adopts a dual-function adsorbent with adsorption-hydrogenation reduction. The regeneration desorption adopts the method of hydrogenation reduction. The regeneration temperature is low, the life of the adsorbent is long, and the requirements for equipment materials are low. , No need to use hot nitrogen or steam to purge and replace before regeneration, low energy consumption, no oxygen for regeneration, no danger of combustion and explosion, and basically no loss of effective materials adsorbed in the adsorbent. Effectively solve the contradictions among factors such as three wastes, energy consumption, material consumption, materials and safety.

Description

technical field [0001] The invention relates to a method for preparing odorless isododecane, in particular to a method for preparing odorless isododecane by hydrogenating and deodorizing isobutene trimers. Background technique [0002] Isododecane is a highly branched saturated dodecane, which does not have the oily smell of low-carbon alkanes, and has a relatively fast volatilization speed. It can be used as a substitute for volatile silicone oil for The skin feels very refreshing when used in cosmetics, and can be widely used in various cosmetics, skin care / hair care products, aerosols and other fields. [0003] Isododecane usually comes from the hydrogenation of isobutylene terpolymer (TIB), but the hydrogenation products generally have a certain odor. Patent CN200480006931 believes that the odor-generating substances are trace oxygen-containing substances generated by the contact reaction between oligoolefins and oxygen. Aldehydes, alcohols, esters and other impurities....

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Problems solved by technology

[0004] In other technical fields, inorganic adsorbents such as alumina and molecular sieves are generally regenerated by roasting after carbon deposition, but the roasting temperature is relatively high, usually between 350-450 °C, and the requirements for equipment materials are very high. And long-term high temperature treatment will destroy the pore structure of the adsorbent

At the same time, the use of oxygen during roasting is very likely to cause combustion and explosion hazards for the hydrocarbons adsorbed in the adsorbent, especially in olefin hydrogenation devices. Therefore, hot nitrogen or steam must be used for blowing before roasting. Sweep replacement, which requires a large amount of nitrogen and steam consumption, and the water in the steam is extremely detrimental to the stability of the alumina adsorption structure

In addition, the odor substances adsorbed in the adsorbent often only account for a relatively small proportion of the adsorbed materials, and a considerable part is effective products or raw materials, but it is difficult to separate the materials in the pores from the adsorbent during the regeneration process. The materials adsorbed in the adsorbent must be disposed of together, resulting in a large loss of effective components

[0005] In short, it is difficult to solve the contradictions among factors such as three wastes, energy consumption, material consumption, equipment materials and safety when deodorizing products in the production process of isododecane through the existing technology

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