Chlorine trifluoride synthesis method

Abstract

The invention discloses an energy-saving and emission-reducing chlorine trifluoride synthesis preparation method, which comprises the following steps of: adopting mixed gas of raw material fluorine gas and nitrogen gas, enabling the mixed gas and chlorine gas to firstly enter a static mixer to be fully mixed, enabling the mixed material to enter a heat recoverer, preheating the raw material in the material, pre-cooling the product, and recycling the reaction heat, thereby achieving the energy-saving effect; raw materials are preheated and then enter a tubular reactor, reaction products are cooled by a heat recoverer and then enter an adsorption column, hydrogen fluoride impurities generated by reaction are adsorbed and removed, the reaction products enter a condenser after the hydrogen fluoride impurities are removed, the raw materials are liquefied and then enter a gas-liquid separator, a liquid phase enters a collection steel cylinder, and chlorine trifluoride is obtained. According to the invention, the reaction heat is recycled, the energy consumption of the device is low, hydrogen fluoride impurities can be removed, and the reaction yield is high, the product purity is high and the reaction yield is high.

Description

technical field [0001] The invention belongs to the field of gas purification, in particular to an energy-saving synthesis method of chlorine trifluoride. Background technique [0002] As a cleaning gas for semiconductor production, chlorine trifluoride (ClF3) has been used in low-pressure chemical vapor deposition (LPCVD) of polysilicon, SiN, etc. and plasma CVD of non-crystalline alloy silicon. The chemical vapor deposition (CVD) process used in semiconductor manufacturing uses heat or plasma as an energy source to decompose a source gas on a silicon substrate. Film formation reactions in low pressure chemical vapor deposition (LPCVD) are driven by heat from a silicon wafer (cold wall reactor) or a furnace (hot wall reactor). Cold-wall LPCVD reactors are typical single-wafer production units, while LPCVD furnaces process wafers in batches. In a plasma-enhanced chemical vapor deposition process (PECVD), the source gas is decomposed by thermal (~5 eV) electrons in an RF (r...

AI Technical Summary

Problems solved by technology

[0003] Chlorine trifluoride has extremely high reactivity, can basically react with most substances, and is corrosive and highly toxic. It has extremely high requirements for experimental and production process control and equipment materials, making its research, production and application less research

Patent CN104477849B introduces a preparation method of chlorine trifluoride, which uses liquid-phase chloride and fluorine gas to react to obtain chlorine trifluoride. This method has a high conversion rate and the by-products are easy to separate, but the reaction is between It is carried out at a temperature of 400°C, and the heat of reaction is not recycled. The energy saving of the process equipment needs to be improved.

Patent CN104477850B introduces a method in which fluorine gas, chlorine gas and dilution gas enter a catalytic reactor to react to obtain chlorine trifluoride, which shortens the length of the reactor and simplifies the production process. The reaction is also carried out at a temperature of 100-400°C , and no reaction heat recovery

At the same time, because hydrogen fluoride is inevitably produced in the process of generating chlorine trifluoride, neither of the two patents describes the method of removing hydrogen fluoride impurities, and both patents use packed reactors, and the temperature distribution inside the reactors is not uniform