Investigation of Kinetics and Isotherms of Boron Adsorption of Water Samples by Natural Clinoptilolite and Clinoptilolite Modified with Sulfuric Acid

One of the major concerns of industrial toxic heavy metals such as boron in wastewater petrochemical industry. In this study, a comparison between natural and modified clinoptilolite with sulfuric acid as a low-cost adsorbent to remove boron from aqueous solutions has been made. The results show that the modified clinoptilolite more willing to absorb boron compared to the unmodified clinoptilolite. In addition, parameters such as initial concentration of boron, sorbent particle size, pH, adsorbent dosage and direct contact with the absorber and the absorption solution containing boron contaminants effectively. The optimum amount of boron absorbed by the modified clinoptilolite at pH=8 was obtained. The balance between absorbent and adsorbent contact time of 240 minutes and 480 g/L of the adsorbent optimal amount of clinoptilolite modified to obtain maximum absorption efficiency was appropriate. Removal of boron by clinoptilolite modified in optimal conditions %92/35. So Clinoptilolite modified with sulfuric acid has a high potential for use in industrial wastewater treatment plants. Also included Langmuir isotherm between the three models, Freundlich and Dubinin-Radushkevich boron model Freundlich adsorption on clinoptilolite modified sorbent well described. Boron adsorption kinetics models on absorbent natural clinoptilolite and clinoptilolite modified based on kinetic models Lagergren and Ho and colleagues and particle diffusion model was investigated and that the pseudo-second model more consistent with the experimental data and as a kinetic model of this process was introduced.