title: Relation between some two- and three-parameter isotherm models for the sorption of methylene blue onto lemon peel.
abstract: Equilibrium uptake of methylne blue onto lemon peel was fitted to the 2 two-parameter isotherm models namely Freundlich and Langmuir and 3 six-parameter isotherm models namely Redlich-Peterson, Toth, Radke-Prausnitz, Fritz-Schluender, Vieth-Sladek and Sips isotherms by non-linear method. A comparison between two-parameter and three-parameter isotherms was reported. The best fitting isotherm was the Sips isotherm followed by Langmuir isotherm and Redlich-Peterson isotherm equation. Redlich-Peterson isotherm is a special case of Langmuir isotherm when the Redlich-Peterson isotherm constant g was unity. Radke-Prausnitz, Toth, Vieth-Sladek isotherm were the same when the Toth isotherm constant, n(T) and the Radke-Prausnitz isotherm, m(RP) are equal to unity and when the Vieth-Sladek isotherm constant, K(VS) equals zero. The sorption capacity of lemon peel for methylene blue uptake was found to be 29 mg/g.
authors.forename: K Vasanth
authors.initials: KV
authors.lastname: Kumar
authors.forename: K
authors.initials: K
authors.lastname: Porkodi
mesh_terms: D000327:Adsorption; D002957:Citrus / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D008751:Methylene Blue / Q000737:chemistry* / Q000302:isolation & purification*; D008956:Models, Chemical; D012996:Solutions
chemical_list: D012996:Solutions; D008751:Methylene Blue