Novel Adsorbent from Biowaste (Shrimp Shells): Metal-Impregnated Activated Carbon for Efficient Dye Removal

Activated carbon (AC) is a valuable material utilized in multiple sectors owing to its versatility and ability to absorb various compounds effectively. Its adsorption characteristics are due to a large surface area and extensive porous network. Metal impregnation into activated carbon is for the improvement of its adsorption capacity and the elimination of specific contaminants like heavy metals, organic pollutants, or gases assessing with long-term performance. The chitosan derived from shrimp shells has the property of dye adsorption. Such a polymer chitosan with adsorption property is reformed into activated carbon by pyrolysis to enhance its adsorption ability in the removal of hazardous dyes. Field Emission Scanning Electron Microscopy (FESEM) of the AC showed a porous surface. Aluminium (Al), Iron (Fe), and Silver (Ag) were incorporated into the activated carbon individually by simple chemical method, at low temperatures. The structural investigation results give the Ag-imposed AC forms in a polycrystalline phase with crystallite size in the nanoscale. FTIR data of metal-imposed AC proves that chemical modification occurs in activated carbon by the inclusion of metals. The adsorption of Rhodamine 6G and Amaranth dyes by AC/Al, AC/Fe, and AC/Ag were investigated by UV analysis. This work shows that about 47% concentration of Amaranth dye was adsorbed by AC/Al composite, and to the maximum 21% of Rhodamine was adsorbed by AC/Ag sample in an experiment time of 10 hours at room temperature.