Investigation of a two impinging-jets contacting device for liquid-liquid extraction processes

A two impinging-jets contacting device (TIJCD) for liquid-liquid extraction processes was proposed and tested through the standard test system recommended by the European Federation of Chemical Engineering (EFCE), toluene-acetone-water, as a typical example of liquid-liquid extraction processes. The results obtained for the overall volumetric mass transfer coefficient (capacity coefficient) were more than three times higher than those reported in the conventional contactors and in an air-driven two impinging-streams contactor. These experimental results clearly indicate the greater performance capability of TIJCD relative to those of conventional contactors. To have a perfect study on the pertinent parameters of the TIJCD, the influence of jets momentum, nozzles diameter and the inter nozzle distance have been investigated. In addition, the enhancing effect of the impingement zone has been studied using a non-impinging-jets contacting device. Based on the experimental data obtained, an increase in the liquid flow rates results in an increase in the extraction efficiency and overall volumetric mass-transfer coefficient, while increasing the distance between nozzles decreases the extraction efficiency. In addition, it was found that the effect of nozzle diameter on the extraction efficiency could be dependent upon the jets velocity.