Effect of reactional parameters on the elimination of Congo Red by the combination of coagulation–floculation with aluminum sulfate
Sarah Goudjil, Saâdia Guergazi, Toufik Masmoudi, Samia Achour
Abstract
ABSTRACT The main objective of our study is to test the performance of aluminum sulfate (AS) and the coagulation–flocculation process in removing a dye widely used in the textile industry called Congo Red (CR). In order to achieve our objective, the jar-test tests were carried out in the laboratory on synthetic solutions. Various reaction parameters were tested such as the effect of variation in coagulant dose, variation in initial CR content, and variation in pH. A combination between the AS and coagulants aid such as powder activated carbon (PAC), polymers, and lime (Ca(OH) 2 ) has been carried out to improve this process. The results obtained indicated for 30 mg/L concentration of CR, the AS optimal dose is found 40 mg/L. This dose has an elimination yield around to 97.24%. For the pH effect, the best performance was achieved in the range of pH between 4 and 6. Similar efficiency trends were obtained for 50 mg/L of the initial content of the CR. The combination of AS with coagulants aid has also shown that there is a very strong elimination marked by the small amounts of polymer, where the yield exceed 99%, in comparison with PAC and lime.