Is it difficult to maintain green water and green mountains in the Organosilicon monomer production process? –Nanjing Shinkai realize the “gold mountain and silver mountain”for you!

Organosilicon monomer (organosilicon monomer), mainly refers to the raw materials used to synthesize organochlorosilane polymer materials, from cell phones or medical and aesthetic use of soft silicone protective cover or prosthesis, to 5G base stations or photovoltaic module sealing and encapsulation materials, are indispensable to organosilicon monomers of this chemical raw material.

Common silicone monomers such as methyl chlorosilane, its core structure is the silicon atom (Si) connected to organic groups (such as methyl -CH3) and chlorine atoms (Cl), of which dimethyldichlorosilane ((CH3)2SiCl2) is the main raw material for the manufacture of silicone oils, silicone rubbers and other chemical industry products, methyl trichlorosilane (CH3SiCl3) is characterized by cross-linking and curing, is the “protagonist” in the sealants and coatings. Sealants and coatings in the “protagonist”. The structure of other common silicone monomers is shown in the figure below.

The raw materials needed for the production of organosilicon monomers are industrial silica powder and chloromethane, while in order to improve the yield of organosilicon monomers, Cu/Si composites or Zn-Cu alloys are often used as catalysts, where Cu can form active sites on the surface of the silica powder, and the Zn-Cu catalysts provide a selective way to enhance the yield of dimethyldichlorosilane.

Filtration and Separation in Production Processes
In the process steps of organosilicon monomer synthesis, the recycling of catalysts, the transportation of powders, as well as the emptying and venting of storage tanks, are all indispensable to the role of the filter, which not only reduces the pollution of the environment, but also ensures the safety of the process and the reliability of the operation.

Conventional filtration separation difficulties:
Improving the selectivity of dimethyl dichlorosilane, reducing raw material and energy consumption, and ensuring production and environmental safety are long-standing goals to be achieved in silicone production. In the traditional filtration method, the following problems often occur:

• Conventional cyclone separation + scrubber tower with silica powder recovery of about 80-85%;
• The copper-based catalyst (Cu/Si complex) gradually wears out during the reaction and partly escapes with the gas stream, leading to increased catalyst replenishment costs;
• Reaction exhaust gas contains a large amount of <10μm silica powder and metal chlorides, easy to scale on the surface of the cartridge, requiring frequent cleaning downtime;
• HCl corrosion (pH < 2) from the hydrolysis of chloromethane (CH3Cl);
• High-temperature resistant ceramic filter is needed when dealing with high-temperature gases, but it is easy to rupture by thermal fatigue in long-term operation;
• Organochlorosilane treatment has a high risk factor. Methylchlorosilane mixtures are flammable and explosive, and when exposed to water or humid air, they will react violently, releasing toxic and corrosive hydrogen chloride gas, which can cause serious burns to the skin, eyes and respiratory tract;
• The washing tower slurry treatment volume is large, and the cost of equipment, labor and energy consumption is high.

Shinkai Patent: Gas-Solid Separation Device for Fluidized Bed of Organosilicon Monomer Synthesis
Shinkai Filtration owns the utility model patent (CN209885776U)[1] developed independently. The metal filter designed and manufactured by ourselves is widely used in the separation of gas-phase products and solid particles by virtue of its advantages of high-temperature resistance, corrosion resistance, and high precision, which greatly reduces the handling capacity of the subsequent processes:

• Effectively separating solid particles with particle size within 0.5-10 um, the interception rate can reach 100%, avoiding the blockage of subsequent equipment.
• At the same time of filtration, the metal membrane cartridge can be regenerated by on-line pulse blowback, avoiding downtime for dismantling and washing, and realizing continuous production;
• The recycling of catalyst and silica powder can be realized, and the filter cake is automatically discharged to the recycling powder tank after backblowing;
• Fully automated control, airtight design, realizing safe and efficient operation;
• High temperature and corrosion resistance, such as Hastelloy C-276 resistant to HCl and silicone compound corrosion;
• Large processing capacity, single filter filtration area of up to 500 m2, and can be more than one parallel connection;
• Small pressure head loss, stable operation pressure drop of about 3 kPa.
• Instead of washing tower, reduce energy consumption, and no slurry discharge.

Whether it is fluidized bed silica powder recovery, efficient catalyst retention, powder conveying exhaust filtration, or exhaust gas purification to meet the standards, Shinkai filtration systems have been verified by many silicone manufacturers. For example, in a silicone project with an annual output of 400,000 tons, a high-temperature online blowback filtration system designed and supplied by Nanjing Shinkai was adopted, in which the technology uses Shinkai’s unique utility model patent for gas-solid separation, which practically reduces energy consumption in the production of the customer and reduces the waste of reaction products and catalysts, effectively eliminating the pressure on safety and environmental protection. It reduces the energy consumption of the customer in the production, and at the same time reduces the waste of reaction products and catalysts, effectively eliminates the pressure of safety and environmental protection, and helps the customer to ensure the stability of product quality, which has significant economic and environmental benefits.
If you have related needs, please feel free to contact Shinkai team!