Adsorption of Anionic Surfactant Presence in Synthetic Car Wash Wastewater by Limestone
Limestone (LS) is a natural carbonated rocks that is porous with the scatterings of minerals on the surface with potentially active surface. In this study, raw LS were observed to perform efficiently in treating synthetic car wash wastewater (CWW) that was prepared using commonly used anionic surfactant (AS); sodium dodecyl sulphate (SDS). The point zero charge (PZC) of LS were determined using salt addition method and resulted with the result of pHPZC 8.05. Overall, the LS used in this study was found to perform efficiently at pH 2, with the removals of chemical oxygen demand (COD) and AS at around 30% and 50% respectively and the adsorption capacity of COD and AS around 0.25 and 0.30 mg/g respectively. Overall, LS shows promising potential to be used in the treatment of AS presence in wastewater with requirement of additional optimization of other parameters (such as dosage, contact time, salt addition, etc.) to enhance the efficiency.