CLEANING AGENT FOR GAS CONTAINING SILICON CHLORIDE AND METHOD FOR CLEANING

PROBLEM TO BE SOLVED: To obtain a cleaning agent having excellent purification ability for gas to be treated even when the concentration of silicon chloride in the gas is low or even when the gas is a dry gas, by using copper (II) oxide having a specified or higher BET specific surface area and a hydroxide of alkali metal as the main components. SOLUTION: This cleaning agent is prepared from copper (II) oxide having >=10 m2/g BET specific surface area and a hydroxide of alkali metal as the main components. High purification ability is obtained by bringing the gas to be treated into contact with the cleaning agent even when the concentration of silicon chloride in the gas is low or even when the gas is a dry gas. In this method, as for the hydroxide, potassium hydroxide is used, and its content is controlled to 1 to 15 wt.% in the dry cleaning agent. The silicon chloride is selected from monochlorosilane, dichlorosilane and trichlorosilane. The concentration of silicon chloride in a harmful gas is specified to