The harnessing of natural zeolite for adsorption of methylene blue active substances from carwash wastewater: A kinetic and isotherm study

The removal of surfactants from wastewater is critically important, particularly in Jordan, which is the third-most water-scarce country in the world.Jordan is rich in natural zeolite, a highly absorbent material, making it ideal for removing liquid-solid contaminants like surfactants from wastewater.This study investigates the adsorption capacity of zeolite to remove methylene blue active substances (MBAS) from carwash wastewater (CWW) using batch-sorption experiments.Various parameters, including zeolite dosage, contact time, and temperature, were tested to evaluate their impact on the sorption process.he results demonstrate that natural zeolite achieved a maximum removal efficiency of 93.02%, with optimal performance at pH 6.8.Dosages of 0.1, 0.5, and 1.0 grams were tested, revealing that increased zeolite dosage, longer contact times, higher temperatures, and lower initial concentrations enhanced removal efficiency.The best removal efficiency for SDBS-MBAS was achieved within a 30-minute mixing time.At a dosage of 1 gram, the adsorption coefficient rose from 6.3% to 23.5% as temperature increased from 25 C to 45 C, indicating an endothermic process.The adsorption was found to be endothermic, spontaneous, and irreversible.Additionally, adsorption isotherm models, including Langmuir, Freundlich, and Pseudo-second-order, were applied to analyze the adsorption behavior.The Langmuir model provided the best fit, while the Freundlich model showed the highest error values.Error analysis confirmed the validity of the Pseudosecond-order and Langmuir models for describing the adsorption kinetics.