The difference between cold hydrogenation and chlorohydrogenation

I. The difference between cold hydrogenation and chlorohydrogenation lies in whether hydrogen chloride is added during the reaction process; this is described as follows: 1. Silica powder reacts with silicon tetrachloride, hydrogen gas, and hydrogen chloride gas in a gas-solid fluidized state at around 550°C and a pressure of approximately 3.5 MPa, to produce a silane mixture containing a certain proportion of trichlorosilane. This reaction process is what is known as chlorohydration; its main chemical equation is as follows: Si + 2SiCl4 + H2 + HCl = 3SiHCl3. 2. In the absence of hydrogen chloride gas, silicon powder, silicon tetrachloride, and hydrogen undergo a gas-solid fluidization reaction within an FBR reactor – this is what is known as thermal hydration, with the main chemical equation being: Si + 3SiCl4 + 2H2 = 4SiHCl3. II. Since chlorohydration solves the problem of hydrogen chloride recovery in the CDI process, it is not necessary to use a trichlorosilane synthesis unit in the production setup; therefore, chlorohydration is currently the preferred method in China. III. It should be chlorohydration at the **enterprise in Xuzhou; I’ve only heard about it though, with no detailed knowledge on it!

This post was last edited by king2401 on 2011-7-25 08:32 ............................................Eyes

Moderator, the thermal hydrogenation you mentioned refers to a gas-solid fluidized reaction involving silicon powder, silicon tetrachloride, and hydrogen in an FBR reactor; this should be considered cold hydrogenation as well. Currently, in all companies, thermal hydrogenation involves a reaction between hydrogen and silicon tetrachloride.

Reply to 5# hchg0615: It refers to cold hydrogenation and chlorohydrogenation; the term \"hot hydrogenation\" is not used in this post. Chlorohydration preceded cold hydrogenation; when cold hydrogenation was first introduced from abroad, the technical barriers were very high, and foreign parties were not willing to provide effective solutions. China was the first to dare to use chlorohydration, and many patented technologies were developed over time, leading to the advancement of cold hydrogenation. However, cold hydrogenation also involves the use of hydrochloric acid.

Haiyou on the 2nd floor: That’s a good point! Like it! Cryohydration: 3SiCL4 + 2H2 + Si → 4SiHCl3. Chlorohydration: 3SiCL4 + 2H2 + Si + 3HCl → 5SiHCl3. The difference is obvious; in chlorohydration, HCl participates in the reaction. Xuzhou Zhongneng can handle both cold hydrogenation and chlorohydrogenation. Currently, cold hydrogenation is the mainstream technology. Currently, major design institutes in China such as the Eighth Research Institute are carrying out designs to achieve high efficiency through continuous operation due to considerations related to temperature and pressure. It has a significant impact on the equipment used, and the operating conditions are quite harsh. Other hydrogenations will soon be developed to replace cold hydrogenation and chlorohydrogenation. Interested in discussing privately.