Synthesis, characterization and application of Carboxylmethyl cellulose, Guar gam, and Graphene oxide as novel composite adsorbents for removal of malachite green from aqueous solution

The preparing biopolymer composite adsorbents for environmental friendliness applications remarkably attracted much attention. Herein, novel biopolymer nanocomposite of carboxymethyl cellulose (CMC), guar gum (GG), and graphene oxide (GO) was used to prepare the CMC/GG and CMC/GG/GO with different weight percents of GO (1, 3, and 5% denoted as CMC/GG/GO-1, CMC/GG/GO-3, and CMC/GG/GO-5, respectively) and their performance for removing cationic dye (MG: malachite green) from aqueous solution was studied. XRD, FTIR, SEM, EDX, and BET analyses were used to characterize the materials. Influential parameters such as adsorbent amount, initial dye concentration, contact time, temperature, and pH on the removal efficiency of contaminant from aqueous solutions were investigated. CMC/GG/GO-3 nanocomposite was selected as the optimal, and the max adsorption capacity 17.6 mg/g and removal efficiency 88.2% were obtained. Isotherm data (Langmuir, Freundlich, and Temkin) showed that the Langmuir isotherm corresponds to a correlation coefficient of 0.98. Thermodynamic data indicated that the adsorption was a spontaneous and endothermic process. Also, the study of pseudo-first-order and pseudo-second-order kinetic models signed a good agreement with the pseudo-second-order with R-2 = 1.

Automated summary

This study used biopolymer nanocomposite materials to prepare adsorbents with excellent performance. The effects of different factors on the removal efficiency of contaminants were investigated, and the optimal nanocomposite material was found, with a maximum adsorption capacity of 17.6 mg/g and a removal efficiency of 88.2%. The isotherm data indicated that the Langmuir isotherm was the most suitable model for describing the adsorption process. The thermodynamic data and kinetic models were also validated.