Equilibrium and kinetic studies on sorption of basic dyes by a natural biopolymer poly(γ-glutamic acid)

被引:97
作者
Inbaraj, B. Stephen
Chien, J. T.
Ho, G. H.
Yang, J.
Chen, B. H. [1 ]
机构
[1] Fu Jen Catholic Univ, Dept Nutr & Food Sci, Taipei 242, Taiwan
[2] Vedan Enterprise Corp, Taichung 400, Taiwan
关键词
adsorption; poly(gamma-glutamic acid); polypeptide; basic dyes; modelling; kinetic parameters; isotherm parameters;
D O I
10.1016/j.bej.2006.08.001
中图分类号
Q81 [生物工程学(生物技术)]; Q93 [微生物学];
学科分类号
071005 ; 0836 ; 090102 ; 100705 ;
摘要
A bacteria-derived biodegradable and non-toxic biopolymer poly(gamma-glutamic acid) (gamma-PGA) was evaluated as an adsorbent for removal of basic dyes from aqueous solution. Sorption experiments were carried out with three basic dyes Auramine O (Au-O), Rhodamine B (Rh-B) and Safranin O (Sa-O) by a batch mode at different initial dye concentrations, agitation times, gamma-PGA doses, temperatures, pH and added salts. Sorption isotherms were well described by the Redlich-Peterson equation, closely followed by Sips, when compared to Freundich and Langmuir models. The maximum sorption capacity derived from Langmuir model at 301 K was 277.29, 390.25 and 502.83 mg/g for Au-O, Rh-B and Sa-O dyes, respectively. The kinetics of dyes sorption on gamma-PGA followed a pseudo second order equation and the rate was controlled by chemical sorption. An ion-exchange model assuming adsorption to be a chemical phenomenon also predicted the kinetic data precisely. Thermodynamic parameters (Delta H degrees, Delta S degrees and Delta G degrees) obtained revealed dye sorption to be an exothermic and spontaneous process with decreasing randomness of dyes at the solid/solution interface. Dye sorption increased with increase in solution pH and reached a plateau at pH 5, while desorption of about 98% of dyes from spent gamma-PGA occurred at pH 1. The incorporation of salts decreased the dye sorption, suggesting the binding of dyes on gamma-PGA may involve ion-exchange mechanism. (c) 2006 Elsevier B.V. All rights reserved.
引用
收藏
页码:204 / 215
页数:12
相关论文
共 42 条
[1]   Novel poly-glutamic acid functionalized microfiltration membranes for sorption of heavy metals at high capacity [J].
Bhattacharyya, D ;
Hestekin, JA ;
Brushaber, P ;
Cullen, L ;
Bachas, LG ;
Sikdar, SK .
JOURNAL OF MEMBRANE SCIENCE, 1998, 141 (01) :121-135
[2]   Natural polysaccharides and their interactions with dye molecules: Applications in effluent treatment [J].
Blackburn, RS .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 2004, 38 (18) :4905-4909
[3]   REMOVAL OF HEAVY-METALS FROM WATERS BY MEANS OF NATURAL ZEOLITES [J].
BLANCHARD, G ;
MAUNAYE, M ;
MARTIN, G .
WATER RESEARCH, 1984, 18 (12) :1501-1507
[4]   THE EXCHANGE ADSORPTION OF IONS FROM AQUEOUS SOLUTIONS BY ORGANIC ZEOLITES .2. [J].
BOYD, GE ;
ADAMSON, AW ;
MYERS, LS .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1947, 69 (11) :2836-2848
[5]   Single and multicomponent equilibrium studies for the adsorption of acidic dyes on carbon from effluents [J].
Choy, KKH ;
Porter, JF ;
McKay, G .
LANGMUIR, 2004, 20 (22) :9646-9656
[6]  
Clark G., 1981, STAINING PROCEDURES
[7]   Adsorption of CI Basic Blue 9 on cyclodextrin-based material containing carboxylic groups [J].
Crini, G ;
Peindy, HN .
DYES AND PIGMENTS, 2006, 70 (03) :204-211
[8]   Non-conventional low-cost adsorbents for dye removal: A review [J].
Crini, G .
BIORESOURCE TECHNOLOGY, 2006, 97 (09) :1061-1085
[9]   Recent developments in polysaccharide-based materials used as adsorbents in wastewater treatment [J].
Crini, G .
PROGRESS IN POLYMER SCIENCE, 2005, 30 (01) :38-70
[10]  
DO DD, 1989, ASORPTION ANAL EQUIL