1. Silicon tetrachloride can be prepared by passing dry chlorine over an intimate mixture of silica and carbon by heating to 1675 K in a porcelain tube.
SiO2 + 2C + 2Cl2 → SiCl2 + 2CO
2. On commercial scale, reaction of silicon with hydrogen chloride gas occurs above 600 K.
Si + 4HCl → SiCl4 + 2H2