The First Application of Moroccan Perlite as Industrial Dyes Removal

Abstract

A local perlite mineral (P1) was used to remove the industrial dyes Remazole Brilliant 19 (RB19) and Drimarene Yellow (YD) from an aqueous solution. Prior to any investigation, P1 was characterized using powder X-ray diffraction, Fourier transformed infrared spectroscopy, scanning electron microscopy, X-ray fluorescence, Brunauer-Emmett-Teller analysis, and electrophoretic mobility in order to establish the adsorption behavior-properties relationship. We used a sequential methodology of factorial design of experiments (DOE) and response surface methodology (RSM) to evaluate experimental variables that influence the adsorption process. Under optimal conditions, removals of RB19 and YD were achieved at respectively 95% and 88%. The validity of the process was justified by the values of three statistical indicators: Fisher’s high value (F = 58.79 for RB19, F = 34.82 for YD), the probability P (P ≤ 0.001 for DY and RB19) and the coefficient of determination R2 (0.9674 for YD and 0.9821 for RB19). The mass transfer of RB19 and YD at the solution/adsorbent interface was described using a pseudo-second-order rate law. The adsorption process for RB19 was endothermic, while it is exothermic for YD. The phyto-toxicity was also investigated to evaluate the toxicity level of YD and RB19 before and after sorption on P1 material. Overall P1 is very attractive as an efficient, low-cost and eco-friendly sorbent for the remediation of hazardous organic pollutants in industrial effluents.