Carbon disulfide-modified polyvinyl alcohol/sodium alginate adsorbent for removing Cu(II) from electroplating wastewaters

Copper-rich effluents generated from electroplating activities pose notable environmental risks owing to their high metal content and strong complexation behavior. This study first prepared the adsorbent PVA/SA by crosslinking polyvinyl alcohol (PVA) and sodium alginate (SA), then further modified it with carbon disulfide (CS₂) under alkaline conditions to produce the new adsorbent material DT-PVA/SA. This material effectively removes Cu(II) ions from water primarily through physical adsorption, electrostatic interactions, coordination reactions, and ion exchange. Experimental results show that DT-PVA/SA exhibits strong selective adsorption capacity for Cu(II) and is resistant to interference, with a maximum adsorption capacity of 133.87 mg/g. At room temperature, 1.2 g/L of DT-PVA/SA can remove 50 mg/L of Cu(II) with 100% efficiency. At 55°C, complete removal is achieved with only 0.6 g/L of DT-PVA/SA. This study indicates that DT-PVA/SA gel microspheres, as a new adsorbent, have excellent potential for removing Cu(II) from wastewater, providing new insights and materials for electroplating wastewater treatment.