The effect of liquid additives on dry ultrafine grinding of quartz

The dry ultrafine grinding of quartz with liquid additives was carried out using a vibration rod mill with a laboratory scale. Liquid additives used were mainly seven alcohols and three glycols with different alkyl groups. All of the experiments were carried out by batch operation, and the variations of specific surface areas of products with grinding time were measured by BET adsorption method. The results showed that alcohol and glycol additives were satisfactorily effective for the ultrafine grinding of quartz. The maximum specific surface area of quartz obtained with an additive was found to increase in proportion to the amount of the additive. The additive molecules of multimolecular layers were supposed to adsorb on the quartz surface when the specific surface area reached the maximum value. The principal effect of additives in ultrafine grinding is considered to be the increase in flowability and the control of reagglomeration of quartz powder due to the alkoxylation of hydroxyl groups on the quartz surface. (C) 2001 Elsevier Science S.A. All rights reserved.