Phenol-Contaminated Water Treatment Using Clay Nano Particles in Continuous and Batch Process and Survey the Factors Affected

Abstract

Phenols and their derivatives are aromatic compounds containing hydroxyl or sulfonic groups attached to a benzene ring structure. Even in low concentrations, phenols are hazardous pollutants posing a threat to living organisms. This study explored the removal of phenol utilizing nano clay modified with hexadecyltrimethylammonium (HDTAM) cations. The research was conducted in three phases. The first phase involved batch experiments to eliminate phenol from aqueous solutions. In the second phase, modified nano clay was applied in a continuous system for practical purposes, investigating the impact of varying clay concentration and weight in the adsorption column. The third phase focused on studying the performance of columns in series. The results from the initial phase indicated equilibrium between the solution and adsorbent after approximately one hour, a significant reduction compared to the unmodified nano clay. Increasing the initial concentration of phenol from 50 to 800 milligrams per liter led to enhanced adsorption capacity but decreased removal efficiency from 70% to 45%. Kinetic studies revealed a pseudo-second-order adsorption process; isotherm studies indicated adherence to both the Langmuir and Freundlich models, with greater conformity to the Freundlich isotherm. The adsorption-separation model derived from the experiments suggested surface adsorption as the primary process at low concentrations, transitioning to dominant separation with increasing concentration. The second phase demonstrated the effective performance of modified clay in continuous processes, with higher flow rates resulting in reduced efficiency and adsorption capacity of phenol. Utilizing the modified clay in the adsorption column increased the phenol adsorption capacity and efficiency from 14.5% to 27%. Finally, employing two columns in series in the third phase boosted adsorption capacity from 37% to 50%.

Keywords

• phenol
• wastewater treatment
• modified nanoclay
• hdtma
• adsorption process