Cellulosic Fabric Wastes Grafted with DMAEMA for the Removal of Direct Dyes

Dimethylaminoethyl methacrylate (DMAEMA) was grafted onto a cellulosic fabric waste via γ-irradiation ( 60 Co). Factors affecting the grafting such as the radiation dose and monomer concentration were investigated. The grafted fabric waste was studied by infrared (FT-IR) spectroscopy and thermogravimetric analysis (TGA), as well as its surface morphology. The ability of the grafted fabric waste for removing Direct Violet 31 from its aqueous solution was studied by batch experiments. The adsorption data obeyed the Langmuir and Freundlich isotherms. It was found that 1 g of grafted fabric waste adsorbed 40 mg of Direct Violet 31 from its aqueous solution. The grafted fabric waste could be used as an adsorbent for water pollutants such as dyes, thereby solving one of the most important environmental problems of the textile industry

γ-Induced Graft Copolymerization onto Cellulosic Fabric Waste for Cationic Dye Removal

Radiation grafting of itaconic acid (IA) onto cellulosic fabric in the presence of dimethylformamide (DMF) as a solvent by the mutual method is discussed. Factors affecting the radiation graft copolymerization were investigated. These factors include the radiation dosage, the monomer concentration and the solvent. The grafted samples were characterized using FT-IR spectroscopy, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). Utilization of the grafted cellulosic fabric waste in the removal of Methylene Blue (MB) from aqueous solution was examined. The adsorption data showed that the maximum adsorption capacity of Methylene Blue onto grafted cellulosic fabric waste was 38 mg/g. The adsorption data also obeyed the Langmuir and Freundlich isotherms

Enhancement of the Adsorption of Co(II) and Ni(II) Ions onto Peanut Hulls through Esterification Using Citric Acid

Peanut hulls were modified chemically by esterification with citric acid under conditions which yielded hulls rich in carboxyl content. The esterified products thus obtained were used in the removal of Co(II) and Ni(II) ions from aqueous solutions. The factors affecting the esterification reaction and the adsorption of the metal cations onto the peanut hulls before and after esterification were thoroughly investigated. The results obtained highlighted the following conclusions. The optimum conditions for esterification involve the treatment of peanut hulls (1 g) with 12.4 mmol citric acid in the presence of a very small amount of water for 2 h at 140°C. Similarly, the optimum pH for the adsorption of cobalt(II) ions onto the peanut hulls citrate was 7.0. The adsorption capacity, q e (mg/g), of Co(II) ions onto the peanut hulls citrate increased on increasing the extent of esterification, expressed as mequiv. —COOH/100 g sample. The maximum values for the adsorption capacity, q max , were 28.7 mg/g and 270.3 mg/g on native and peanut hulls citrate, respectively. The q max values for of Ni(II) ion adsorption were 5 mg/g and 175.4 mg/g on native and peanut hulls citrate, respectively. The equilibrium data were well fitted by the Langmuir and Freundlich adsorption models and showed the large capacity of peanut hulls citrate in the removal of Co(II) and Ni(II) ions from aqueous solutions