A Study of Silica Separation in the Production of Activated Carbon from Rice Husk in Viet Nam

Environmental pollution due to mismanagement of the waste from rice production is a serious problem in agricultural countries where rice cultivation occupies the largest proportion of the crops produced, including in Viet Nam. At the same time the use of activated carbon as an adsorption agent for water or gas purification is rapidly increasing due to the development of industry and technology in the developed countries. In this paper we consider the process of separating silica from charcoal, which is an important step in the production of activated carbon from rice husks in Viet Nam. The efficiency of the process rises with increasing temperature up to 133 °C, the ratio of alkali/charcoal up to 0.6 and sodium hydroxide concentration up to 6 M as well. A regression equation has been obtained, which allows describing the influence of the parameters on the degree of silica separation from the carbon. Under optimal values of process parameters, the efficiency reaches up to 95.6%