Cellulose grafted with polyaniline for simultaneous adsorption of cationic and anionic dyes in wastewater effluent

Abstract

The adsorbent for both cationic and anionic dye based on cellulose and polyaniline was prepared.Cellulose was puri ed from sugarcane bagasse through removal of hemicellulose and lignin. Aniline was polymerized in emulsion state in the presence of cellulose and ammonium persulfate as initiator. The FTIR spectroscopy, SEM observation and determination of porosity con rmed that polyaniline was grafted on the surface of cellulose ber to form cellulose-graft-polyaniline with high porosity. Polyaniline acted as adsorption sites for both cationic dye (methylene blue) and anionic dye (methyl orange). The adsorption on the surface of cellulose-graft-polyaniline followed the Langmuir model, suggesting that the adsorption sites on its surface was uniform. The extent of adsorbing capacity of cellulose-graftpolyaniline toward methylene blue and methyl orange was 1.57 and 0.75 mmol/g, respectively. These values con rmed that cellulose-graft-polyaniline was an e cient adsorbent for both cationic and anionic dyes. The adsorption of either cationic or anionic dye in a mixture solution did not restrain each other.Cellulose-graft-polyaniline was expected to have potential application in practical.

Recent Advances in the Removal of Organic Dyes from Aqueous Media with Conducting Polymers, Polyaniline and Polypyrrole, and Their Composites

“…The organic substrates coated with conducting polymers include synthetic polymers, such as carboxymethylcellulose gel [ 78 ], Kevlar fibers [ 73 ], macroporous melamine sponges [ 16 ], poly(ethylene oxide) [ 76 ], polyimide membrane [ 74 ], polystyrene [ 64 ], poly(vinyl alcohol) aerogel [ 42 ], polyurethane foam [ 77 ], and various natural materials, such as [ 24 , 75 ], chitosan [ 82 ], opuntia ficus [ 80 ], almond and wall nut shells [ 81 ] or tea saponin [ 41 ]. Only exceptionally, both components were simply mixed, e.g., polyaniline and nitrogen-containing carbon nanodots [ 87 ] or zinc oxide [ 61 ].…”

“…Many studies agree that polyaniline is an efficient adsorbent or photocatalyst for both anionic and cationic dyes [ 24 , 55 , 91 , 92 ], meaning that ionic interactions are not decisive in their activity.…”

“…The experimental data and the time dependence of the dye concentration decrease are often interpreted in terms of various adsorption models: a pseudo-first-order, a pseudo-second-order, Freundlich, Langmuir, Temkin, or others. The authors found that one of them provided the best fit of the data, with the Langmuir isotherm being the most often winner [ 7 , 8 , 20 , 21 , 22 , 23 , 24 ]. This is the correct approach, but only if the dye removal mechanism is based exclusively on adsorption.…”