Process for removing and recycling dimethyldichlorosilane from hydrochloric acid gas

A technology of dimethyldichlorosilane and hydrochloric acid gas, which is applied in the chemical field, can solve problems such as the impossibility of complete recovery, and achieve the effect of simple method, low operating cost, economical and practical
CN103724367AActive Publication Date: 2014-04-16余家骧
2 Cites 15 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
余家骧
Publication Date
2014-04-16

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention discloses a process for removing and recycling dimethyldichlorosilane from hydrochloric acid gas. A frozen brine graphite cooler is used. The process is characterized by comprising the following steps: volatilizing liquid CH3Cl to obtain low temperature less than -50 DEG C; absorbing dimethyldichlorosilane by using CH3Cl at low temperature; and separating absorption liquid into gas having more than 99.9% (wt) of CH3Cl in purity and a residue having more than 99.9% (wt) of dimethyldichlorosilane through rectification. According to the process, an original frozen brine graphite cooler can be adopted; cooling capacity can be obtained by using evaporation of the residue in an absorption tower so as to cool the raw material HCl to the temperature less than -20 DEG C; the whole process is performed in closed cycle, thus dimethyldichlorosilane in a gas phase of the raw material HCl can be thoroughly removed, the separated dimethyldichlorosilane can be treated up to the standard and returned to a dimethyldichlorosilane hydrolysis step; and the process has the advantages of simplicity in method, economy and practicability, low operation cost, little pollution and environment friendliness.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to the field of chemistry, and relates to a process for removing and recovering dimethyldichlorosilane from hydrochloric acid gas. Background technique

[0002] Existing large-scale organosilicon equipment hydrolyzes dimethyldichlorosilane chloride to generate siloxane by-product hydrochloric acid gas, which is also called HCl gas. Then HCl gas and methanol in saturated ZnCl 2 Chloromethane is generated under the catalysis of the solution, which is also called CH 3 Cl. CH 3 Cl reacts with Si powder in a fluidized bed to form chlorosilanes. Its main chemical reaction equation is:

[0003] n(CH 3 ) 2 SiCl 2 +nH 2 O—→〔CH 3 ) 2 SiO〕 n +2n HCl↑ (1)

[0004] Dimethyldichlorosilane Siloxane

[0005] 2HCl+CH 3 OH—→CH 3 Cl 3 +H 2 O (2)

[0006] Chloromethane

[0007] 2CH 3 Cl+Si—→(CH 3 ) 2 SiCl 2 (3)

[0008] Dimethyldichlorosilane

[0009] The most economical dimethyldichlorosilane hydrolysis method today is t...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More