Removal of Cu (II) by calcinated electroplating sludge

• Main Authors: Thi Huong Tran, Quang Minh Tran, Thi Vinh Le, Thi Thuy Pham, Van Trong Le, Manh Khai Nguyen
• Format: Article
• Language: English
• Published: Elsevier 2021-05-01
• Series: Heliyon
• Subjects: Adsorption; Raw electroplating sludge; Cu (II) removal; Calcinated electroplating sludge; Kinetic study; Adsorption isotherm
• Online Access: http://www.sciencedirect.com/science/article/pii/S2405844021011956

Electroplating sludge consists of various heavy metal oxides, which may be utilized as adsorbent to remove Cu (II) present in aqueous environment. This study evaluated the adsorption performance of calcinated electroplating sludge. The adsorption isotherm based on Langmuir equation proved that calcinated electroplating sludge had a higher adsorption performance than raw electroplating sludge, with maximum adsorption capacity 92 mg/g and 76.34 mg/g, respectively. Findings of the conducted kinetic study revealed that both surface adsorption and intra-particular diffusion were involved during the adsorption process. Moreover, the comparison between the experimental and calculated data of equilibrium adsorption capacity demonstrated that the pseudo second-order kinetic equation fitted well with 38.31 mg/g of calcinated sludge and 33.66 mg/g of raw sludge, approximate to real-world data. Furthermore, adsorption mechanism research demonstrated that while OH group plays a vital role in raw sample, Ca2+, in addition to OH group, was involved in ion exchange in calcinated sample.