Chitosan and Reinforced Chitosan films for the Removal of Cr(VI) Heavy Metal from Synthetic Aqueous Solution

Abstract

Cr(VI) is removed efficiently from aqueous solution using Chitosan made films as the adsorbent. The efficiency of free Chitosan films is compared with the Chitosan-Silica and ChitosanCarbon, which are reinforced with biogenic Silica and Carbon obtained from Panicum miliare husk ashes, respectively. All the films were prepared by simple ageing method and swelling index was determined for all the three adsorbents independently. Adsorption studies of Cr(VI) heavy metal were carried out by varying pH, temperature, initial concentration of the adsorbate and quantity of adsorbent. On the otherhand, Cr(VI) was removed from the solution by Chitosan-Silica film better than free Chitosan and Chitosan-Carbon films. The optimum pH was found to be 3.0 and optimum temperature was 30°C. Thermodynamic, equilibrium and kinetic studies were carried out for all the three adsorbents, independently. Langmuir adsorption isotherm and Pseudo First Order kinetics were followed for the adsorption process. Concentration of metal ions was determined using a spectrophotometer. Oxidation states of the adsorbed Cr were determined by ESR. It was found that Chitosan-Silica film reduced Cr(VI) to Cr(III) almost completely in the aqueous solution.

Swelling behavior and chemical stability of chitosan/nanocellulose biocomposites

“…The weak structure of Cs could not prevent the large amount of alkaline solution from entering, creating a huge osmotic pressure, and disrupting its structure. Thus, Cs can be dissolved in an alkaline solution [17,27]. In our previous work, OPF nanocellulose was reported to be in smaller size as compared with COM nanocellulose.…”

“…This is attributed to the inter and intra hydrogen bonding formation which limits water penetration into the Cs composites. In the works of Srinivasan et al , the swelling of Cs composites was improved up to 100% with the incorporation of silica. Among those reinforcements, cellulose was found to attract more researchers due to its abundance and availability.…”

Adsorption of Thymol Blue and Erythrosine-B on MWCNTs Functionalized by N-(3-nitrobenzylidene)- N'-trimethoxysilylpropyl-ethane-1,2-diamine Equilibrium, Kinetics and Thermodynamic Study

“…The equation and parameter of the isotherm of the research has been reported in Tables 1 and 2, respectively [20][21][22][23][24][25][26] .…”