Efficient adsorption of crystal violet dye using functionalized Argan shell: Experiments and statistical optimization modeling

The disposal of dyeing effluents is an alarming environmental concern; thus, these effluents must be appropriately remediated prior to getting discharged. Herein, citric acid was employed to modify the surface of the Argan shell, which was subsequently utilized as a biosorbent for removing crystal violet dye from water. The asdeveloped material was analyzed by means of scanning electron microscope, infrared spectroscope and X-ray diffractometer. The characterization findings confirm the successful functionalization of Argan shell surface. The adsorption performance of the citric acid-functionalized Argan shell towards crystal violet dye was assessed by examining the influence of operating parameters. The adsorption process tended to fit the pseudo -second order kinetics and Langmuir isotherm. The maximum adsorptive capacity of Argan shell increased from 221.72 to 312.71 mg/g after citric acid functionalization. The crystal violet binding mechanism was attributed to multiple interactions such as electrostatic forces, hydrogen bonds and n-pi interactions. The crystal violet adsorption process on the citric acid-functionalized Argan shell was assessed via response surface methodology. Under optimal conditions, the crystal violet adsorption yield reached 98.14%. Regeneration study revealed that the citric acid-functionalized Argan shell demonstrated an excellent recycling ability. Overall, the citric acidfunctionalized Argan shell holds promise as a stable, efficient and effortlessly recyclable adsorbent for cleaning up colored effluents.