Adsorption of Cr (VI) ion from Aqueous Solution Using Unmodified Desert Date Peels (Balanites aegyptiaca) Composite with MWCNTs: Isotherm and Kinetic Studies

Abstract

Continuous Changing of human lifestyles has consistently added different notorious anthropogenic pollutants into aquatic matrices. Exterminating these toxic pollutants is feasible using adsorption studies instead of the traditional water purification methods. The purpose of this study was to investigate the adsorption of Cr (VI) ion from aqueous using Unmodified Desert Date (UDD) Peels as a low-cost adsorbent and composite with multi-walled carbon nanotubes (UDDC). A batch adsorption experiment was conducted to evaluate the maximum quantity adsorbed of Cr (VI) ions from an aqueous medium under various conditions. The Fourier-Transform Infrared Spectroscopy (FTIR) revealed 3448.84 cm-1 and 3441.12 cm-1 which corresponds to O-H stretching vibration modes for UDD and UDDC and 1620.26 cm-1 relates to C=O stretching vibrations for both UDD and UDDC respectively. The maximum adsorption capacity (qe) is found to be 114.11 and 741.14 (mg/g) for UDD and UDDC respectively. The results showed that UDDC has a large adsorption capacity due to its higher surface area. The adsorption data were fitted well into Langmuir with correlation coefficient (R2) values close to unity 0.9076 and 0.9069 for UDD and UDDC respectively. Kinetic studies showed a good correlation coefficient pseudo-second-order kinetic model fitted very well into UDD and UDDC with (R2) values 0.9173 and 0.9943 respectively. The results indicated that UDDC could be used as a potential adsorbent for the adsorption of Cr (VI) ions from an aqueous solution