Applied Science & Engineering Journal for Advanced Research ISSN (Online): 2583-2468 Volume-1 Issue-3 || May 2022 || PP. 1-13 DOI: 10.54741/asejar.1.3.1 www.asejar.org 1 | Page Biosorption Study of Pb(II) Ions onto Treated Eupatorium adinoforum (AEA) and Acer Oblongum (AAO): Thermodynamic and Equilibrium Studies Dr. Mahesh Chandra Vishwakarma 1 , Dr. Hemant Kumar Joshi 2 , Dr. Sushil Kumar Joshi 3 and Dr. Narendra Singh Bhandari 4 1 Assistant Professor, Department of Chemistry, Govt. Post Graduate College Bageshwar, Soban Singh Jeena University, Uttarakhand, India 2 Guest Lecturer, Department of Chemistry, Nanhi Pari Seemant Engineering Institute Pithoragarh, Uttarakhand, India 3 Professor, Department of Chemistry, SSJ Campus Almora, Soban Singh Jeena University, Uttarakhand, India 4 Professor, Department of Chemistry, SSJ Campus Almora, Soban Singh Jeena University, Uttarakhand, India 1 Corresponding Author: mv.chandra4@gmail.com ABSTRACT In the present study, dried activated biomass of Eupatorium adinoforum (AEA) and Acer oblongum (AAO) used for removal of Pb (II) from synthetic wastewater. The batch operation was conducted with effect of variation of contact time, biosorbent dose, pH, concentration of metal ions and temperature on biosorption of metal ions on biosorbent. Maximum adsorption was recorded for initial metal ion concentration of 10 mg/l, biosorbent dose of 2.5 gm, at pH 5 with 105 minutes of contact time for activated AEA and AAO biomass. The adsorption equilibrium conditions were well described by Langmuir, Freundlich and Temkin isotherm models. The Langmuir isotherm model has provided a better fit with the experimental data in comparison to that of Freundlich and Temkin isotherm models. Thermodynamic data suggest that the bisorption process was spontaneous, feasible and endothermic. The values of thermodynamic parameters suggest that the biosorption process was spontaneous, feasible and endothermic. The kinetics of the biosorption for the reaction mechanism and types of biosorption process onto activated AEA and AAO biosorbent were also discussed. Keywords: metal ions, biosorption, isotherm models, kinetics, ageratum conyzoid (TAC) biomass I. INTRODUCTION Water pollution caused by industrial sewage carrying toxic heavy metal ions is a serious environmental issue. The industrial significance of Lead is its use in batteries, paints, pigments and ammunition, petrol, cables, alloys and steels, plastics, the glass industry and the metal industry 1, 2 . Lead has been introduced in the environment from a variety of sources such as, storage battery, lead smelting, tetraethyl-lead manufacturing and mining, plating, ammunition, ceramic and glass industries. industry, plastics, cables, pigments, and a variety of other anthropogenic wells of heavy metals throughout the environment 1 . Lead is found in the environment in an insoluble form that can cause major health concerns in humans. Lead poisoning is mostly caused by inhaling lead-contaminated dust particles or aerosols, as well as ingesting lead-contaminated food, drink, and paints 1 . The kidney absorbs the most lead in the human body, followed by the liver and other soft tissues including the heart and brain; nonetheless, lead in the skeleton makes up the majority of the body 3 . Lead poisoning is very dangerous to the nervous system. Early indications of lead exposure on the central nervous system include headache, short attention span, irritability, memory loss, and dullness 3, 4 . Encephalopathy, cognitive impairment, behave aural problems, kidney damage, and anemia are all symptoms of excessive lead (Pb) buildup 5 . Lead is a toxic metal that can harm the neurological system and cause mental illness. Long-term exposure to lead can result in nephropathy, gastrointestinal aches, and is especially damaging to women's reproductive function 6, 7 . Lead compounds are poisonous in all forms, but Pb(II) salts and organic lead compounds are the most dangerous. Although Chemical precipitation, filtration, ion exchange, chromatography, and carbon adsorption are some of the methods for removing heavy metals from wastewaters 8-12 . These approaches have a number of drawbacks, including secondary pollutants, high costs, excessive energy usage, and so on 13 . Biosorption is an environmentally acceptable method for removing heavy metal ions from wastewater. In recent years, a variety of biosorbents such as soyabean 14 , Algerian pine, beech and fir sawdust's 15 , modified Cocoa (Theobroma cacao) Pod husk residue 16 , Activated Carbon derived from Sugarcane bagasse 17 , banana (Musa paradisaca) 18 , Rubus ellipticus 19 , Pyras pashia 20 , and Urtica dioica 21 have been employed to remove heavy metal ions from wastewaters. Received: 25-04-2022 Revised: 09-05-2022 Accepted: 17-05-2022