Production of fine fused spherical silica

TLDR: In this paper, the authors proposed to obtain fine fused spherical silica in good yield by melting a silica raw material with a frame formed by combustion of a combustible gas and oxygen and introducing a cooling gas into a flame-forming zone.

Abstract: PURPOSE: To obtain fine fused spherical silica in good yield by melting a silica raw material with a frame formed by combustion of a combustible gas and oxygen and introducing a cooling gas into a flame-forming zone. CONSTITUTION: A silica raw material is melted with a flame formed by combustion of a combustible gas and oxygen to produce fused spherical silica. In the process, a cooling gas is introduced into a frame-forming zone. The silica raw material used is preferably natural or synthetic silica of a as high a purity as possible. Purified quartzite, quartz sand, rock crystal, etc., are cited as the natural silica and silica which is a hydrolyzate of an organosilicate, such as ethyl silicate, prepared by hydrolyzing a silicon halide or neutralizing an aqueous solution of an alkali silica, etc., is cited as the synthetic silica. The above- mentioned silica raw materials are finely pulverized in a desired pulverizer, such as ball mill or jet mill. In most cases, the average particle diameter is ≤10μ, preferably within the range of 2-8μ. COPYRIGHT: (C)1990,JPO&Japio