The Effect of Ethoxylated Alcohols on the Sedimentation Rate of Calcium Carbonate. The Potential for the Use in Flotation Separation of Plastics

ABSTRACT The aim of this study is to determine the potential of using ethoxylated alcohols as surfactants, which improve the sedimentation rate of CaCO 3 in tap water and are applicable for flotation separation of plastics obtained from the WEEE (waste electrical and electronic equipment). Another goal is to determine a surfactant that will not form hard and difficult‐to‐mix crystals in contact with CaCO 3 . Moreover, estimation of the effect of ethoxylated alcohols on the CaCO 3 suspension sedimentation rate in tap water was made. 30% CaCO 3 suspensions in tap water were prepared. Then different kinds of surfactants in that suspension were tested and the stabilities of dispersions were examined. Densities, surface tensions, and sedimentation rates were determined. Moreover, the XRD analyses were performed to characterize differences before and after adding surfactants to the calcium carbonate suspensions. As follows from the research, some ethoxylated alcohols do not form hard‐to‐mix crystals and exhibit better stabilities of dispersion. The best result is a 1.4 improvement of TSI, which proves that ethoxylated alcohols ameliorate the sedimentation rate and can be used as additives in the flotation separation of plastics.