Method for preparing white carbon black from polysilicon byproduct silicon tetrachloride

Abstract

A method for preparing white carbon black from polysilicon byproduct silicon tetrachloride comprises the following steps: introducing silicon tetrachloride into a hydrolysis reaction kettle to conduct hydrolysis reaction and to obtain silicagel and HC1 gas; adding silicagel and sodium silicate into a rotary drum reactor, then adding water to the rotary drum reactor, starting the rotary drum reactor for mixing reaction, separating insoluble impurities, and obtaining clear solution; introducing the clear solution into a precipitation reaction kettle, adding sodium dodecylbenzene sulfonate dispersing agent, adjusting pH value to 8-9, after curing, continuously adjusting pH value to 3.0-5.0, ageing, water washing excessive acid solution, filtering and separating to obtain white carbon black with physical crystal water, then drying and grinding to obtain the product. The invention can most effectively utilize silicagel, has short technical process, relatively simple production equipment and technical operation and can realize industrialized production easily. The white carbon black obtained by the method provided by the invention has high viscosity and intensity, good heat resistance and acid resistance, and other indexes thereof can reach the technical requirement.

Description

technical field [0001] The invention relates to a method for preparing white carbon black from silicon, in particular to a method for preparing white carbon black by utilizing polycrystalline silicon by-product silicon tetrachloride. Background technique [0002] Polysilicon is the main raw material required by the electronics industry and the photovoltaic industry. However, the production of polysilicon produces large amounts of silicon tetrachloride. Silicon tetrachloride is a highly toxic substance, which has a strong irritant effect on the eyes and upper respiratory tract, and seriously pollutes the environment. Therefore, how to effectively use silicon tetrachloride to turn waste into treasure, improve polysilicon production capacity, and realize sustainable polysilicon industry has become a hot topic for enterprises and scholars in recent years. At present, the relatively mature silicon tetrachloride processing technology is as follows: 1. Convert silicon tetrachlori...

AI Technical Summary

Problems solved by technology

The shortcomings of this gas phase method are: high raw material prices, long reaction process, high energy consumption in the production process, and high product prices, which are limited

The shortcomings of this precipitation method are: the activity of the prepared white carbon black is not high, the particles are not easy to control, the affinity is poor, the reinforcing performance is low, and the hydrophilic groups on the surface of the particles are seriously bonded, which weakens the binding force of the product. Production of low-grade products, narrow product application range, and small market capacity

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