Study into the effect of sodium lignosulfonate, anionic surfactants and their mixtures on the rate of copper ion cementation by zinc

Abstract

The article focuses on the effect of sodium lignosulfonate (LS), anionic surfactants (sodium dodecylsulfate (SDS), sodium dodecylbenzene sulfonate (SDBS)), and their mixtures on the rate of copper cementation by zinc. The results obtained demonstrate a decrease in copper cementation rate with the increasing LS and SDBS concentrations. There was also excessive zinc consumption for copper ion cementation noted due to LS and SDBS anion adsorption on positively charged zinc cathodic areas of the cementing agent and the precipitate. This led to a decrease in the rate of copper particle nucleation, energy consumption for forming new copper nucleation centers, and conditions for hydrogen overpotential reduction. In addition, rising temperature led to a decrease in zinc consumption in the presence of LS. Surfactants under investigation may be ranked by the negative impact on copper ion cementation in an ascending order as follows: SDS < SDBS < LS. LS + SDS mixture testing showed its irregular effect on copper cementation rate at test temperatures. Experiments with LS and SDBS mixtures demonstrated a linear decrease in copper ion cementation rate with increasing SDBS concentration and simultaneously rising zinc consumption. Due to the negative impact of investigated reagents discovered, we proposed a method for removing organic impurities from solutions using multilayered aluminosilicates modified by cationic surfactants. The results obtained indicate the high effectiveness of organic impurity removal from solutions providing for a 50 % increase in cementation rate in the presence of LS + SDBS mixture together with a decrease in zinc consumption.