Process Modeling of Methylene Blue Dye Adsorptive Removal by Physio-chemically Treated Cicer arietinum Husk for Effective Wastewater Treatment by Green Chemistry

Abstract

Many reports of detrimental organic dyes in industrial sewages incited the researchers to accomplish some quick, cost-effective, and precise ways for dye eradication. Continuing this research chain, the latest study aimed to exclusively eliminate methylene blue dye (MB) from industrial wastewater using black C. arietinum husk powder as a cost-effective adsorbent through adsorption techniques. Morphological characterization was examined by FTIR and SEM/EDX. The influence of parameters that demonstrated maximum percentage removal such as adsorbent dose (91.325% at 0.4 g), contact time (90.466% at 60 min), pH impact (93.90% at 5), temperature (60.896% at 20 degrees C), and agitation speed (87.03% at 125 rpm) were studied. Adsorption isotherm models (Langmuir, Freundlich, and Temkin) favored Langmuir and represented the finest isotherm data association with maximum monolayer adsorption capacity of 2.678 mg/g. Kinetic studies confirmed the pseudo-second-order model and vindicated the data. The thermodynamic study extended the facts about the exothermic, impulsive, and feasible adsorption nature (Delta H degrees = - 20.329 kJ/mol, Delta S degrees = 0.04305 kJ/mol, and Delta G degrees = - 33.37 kJ/mol at 303 K, - 33.80 kJ/mol at 313 K, - 34.23 kJ/mol at 323 K). Mechanistically, different types of interactions occurred between the adsorbate and adsorbent. MB dye desorption and adsorbent restoration affirm its efficiency. These results indicated that Cicer arietinum husk powder could be used for MB dye eradication from industrial water.