No abstract

Chromium is one of the most significant metals used in the industry. There are many techniques for treating different types of industrial waste water that include chromium ion. In this study, the authors successfully adsorbed the chromium ion from alkaline aqueous solutions using different prepared types of chitosan as adsorbent materials. For the simultaneous sorption behaviour, the adsorption potential of the produced adsorbent was investigated for Cr+6 in a batch system. Natural chitosan was extracted from shrimp shell as it contains about 8–10% chitin which is used in the production of chitosan. The removal percentage of Cr+6 reached 99% after grafting natural and commercial chitosan at specific conditions. Several isotherm models have been used for mechanistic studies. The results indicated that the adsorption data for commercial chitosan is well-fitted by the Freundlich isotherm, Langmuir for commercial grafted, natural and natural grafted chitosan. Kinetic and equilibrium studies showed that the experimental data of Cr+6 were better described by the pseudo-first-order model for commercial chitosan and fitted the pseudo-second-order model for different types of chitosan used. Significantly, in order to scale this effective strategy on an industrial scale, response surface methodology (RSM) was used as a modelling tool to optimise process parameters such as ion concentrations, utilising Statistica Software.

Specific objective for this study was to stabilize a valid method to remove copper from recycled formation water from oil field. Chitosan used for Cu+ 2adsorption from simulated wastewater. Comparison between commercial (CC) and natural prepared chitosan (NC) from shrimps shell, also CC and NC was grafted for enhancing the efficiency of remove tested metal ions. By studying removal of Cu+ 2 across certain parameters as concentration, adsorbent dose, contact time and pH. The results summarized that maximum % removal for all types used was at 20 ppm with value of 94% for CC and NC ,96% for CGC and 98% for NGC after 3hr, 1g and pH = 7. While reaches about 99% removals by increasing adsorbent dose to 4 g for NGC and CGC. Different adsorption isotherms were studied for the remove of Cu+ 2 ions. Also the rate of Adsorption for different types of chitosan used was pseudo 1st order, pseudo 2nd order and Elvoich equation. The kinetic data were analyzed by the intra-particle diffusion model and liquid film diffusion model for Cu+ 2 adsorption using different types of chitosan to study the mechanism of reaction for each type. Significantly, in order to scale up this effective technique on an industrial scale, response surface methodology (RSM) as a modelling tool Statistical Software for further copper ion removal used. The DFT using B3LYP and utilized with 6- 311G* correlation function applied for investigated probs. DFT, and MEPs, also, used to identify the interaction compounds behavior over heavy metal for formation water.