Comparative Study on Cu(II) Adsorption Performance of Self-made and Commercial Activated Carbon

Abstract

Using coconut shell particles as raw material, coconut shell activated carbon was prepared by first carbonizing the particles and then applying chemical activation. The adsorption of copper ions from wastewater by coconut shell activated carbon was investigated, with coconut shell activated carbon and copper ions as the research objects. Experimental instruments including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and ultraviolet-visible spectrophotometry (UV-vis) were employed to analyze the activated carbon and its adsorption performance. The results show that coconut shell activated carbon prepared by carbonization followed by phosphoric acid activation exhibits significantly better Cu(II) adsorption performance than samples activated directly without carbonization and than commercial activated carbon. Under the conditions of a solid-to-liquid ratio of 1:2, an activation temperature of 600 °C, and an activation time of 1 h, the carbonized activated carbon performs best, achieving an adsorption rate of 91.2% and an adsorption capacity of 18.24 mg/g for a 100 mg/L Cu(II) solution. FTIR analysis confirms that after adsorption, the peak positions of oxygen-containing functional groups such as hydroxyl and carboxyl groups shift, and a characteristic Cu—O vibration peak appears, indicating that chemisorption and surface complexation are the dominant adsorption mechanisms. The optimal adsorbent dosage is 0.5 g/L. This study provides a theoretical basis and technical reference for the resource utilization of agricultural and forestry wastes and the low-cost purification of copper-containing wastewater.