Comparative study between Moroccan cactus and chemicals coagulants for textile effluent treatment

The present work shows the results obtained during the treatment of a textile effluent by the process of coagulation-flocculation using three coagulants such as: lime ca(oh)2,ferric chloride fecl3 and aluminum sulfate al2(so4)3. this study also concerns the comparison of these chemical coagulants with a natural coagulant (moroccan cactus). the process efficiency is measured in terms of turbidity,sludge production,heavy metal,absorbance at all wavelengths (200-800 nm) and color removal. the treatment with aluminum sulfate has a significant discoloration and turbidity removal of 98% after 2h settling while producing a sludge volume 360 ml/l. results with fecl3 showed a 97% removal of turbidity and sludge production similar to aluminum sulfate (380 ml/l),but only after 45 min of settling. furthermore,lime having a turbidity removal of about 93 % and a sludge volume lower than the product during the treatment with al2(so4)3 and fecl3. it is,therefore,clear that the settling time plays an important role in the treatment by coagulation flocculation. regarding the analysis of metallic elements,the results showed that a substantial removal of the metallic elements in particularly elements as as cr,cu,fe,mn,zn and ni. the use of the new product from the cactus showed a very significant effect on turbidity removal (96%) accompanied by a net decrease of sludge production (3.3 ml/l) compared to previous coagulants. the settling time is however relatively slow (5 h). the elimination of heavy metals exceeds 91% for cu,cr and zn. these results show that the cactus is non-polluting and could be used in small quantities with a minimum of sludge production for the treatment of a textile effluent. © 2017,university of mohammed premier oujda morocco.