title: Biosorption of dyes using dead macro fungi: effect of dye structure, ionic strength and pH.
abstract: Biosorbents prepared from dead macro fungi, namely Fomes fomentarius and Phellinus igniarius, were applied for the uptake of Methylene Blue (MB) and Rhodamine B (RB). Equilibrium isotherm data could be well described by the Langmuir and Freundlich models. Methylene Blue was found to be more adsorbable than Rhodamine B. Langmuir monolayer coverage was determined as 204.38-232.73 mg/g and 25.12-36.82 mg/g for MB and RB, respectively. Molecular structure and ionic radius of dyes were found to be responsible for differences in their uptakes. Results showed that sorption of MB increased while that of RB decreased as pH of respective dye solutions changed from 3 to 11. An increase in ionic strength also exhibited an adverse effect on dye sorption capacity. Ionic strength and pH affected the sorption of MB more as compared to the sorption of RB. The presence of carboxylic (-ve) and amino (+ve) groups in RB could explain the lower sorption of RB compared to MB.
authors.affiliation: Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi 110 016, India.
authors.forename: Nityanand Singh
authors.initials: NS
authors.lastname: Maurya
authors.forename: Atul Kumar
authors.initials: AK
authors.lastname: Mittal
authors.forename: Peter
authors.initials: P
authors.lastname: Cornel
authors.forename: Elmar
authors.initials: E
authors.lastname: Rother
mesh_terms: D000327:Adsorption; D004396:Coloring Agents / Q000737:chemistry / Q000302:isolation & purification*; D005658:Fungi / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008751:Methylene Blue / Q000737:chemistry / Q000302:isolation & purification; D015394:Molecular Structure; D009994:Osmolar Concentration; D012235:Rhodamines / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D004396:Coloring Agents; D012235:Rhodamines; C029773:rhodamine B; D008751:Methylene Blue