Magnetite encapsulated alginates tailored material for the sustainable treatment of electroplating industrial wastewater: column dynamics and mass transfer studies

摘要

The current study proposes the use of magnetic beads for the treatment of nickel ions of the industrial wastewater system. More specifically, the removal of nickel ions is studied in single and multi-metal ion systems which enabled the scalability of nano-enabled technology to industrial systems. The current synthesis neither involves expensive precursors nor complex procedures. Indeed, the improved surface properties of the adsorbent are due to the use of Lantana camara, in the synthesis. The surface properties and functional attributes of the magnetic beads were characterized by FTIR and SEM analyses. The breakthrough experiments were done for selected column depths, varying feed flow rates and metal ion concentrations. In particular, the interventions of the interfering ions of the electroplating effluents are captured in the breakthrough analysis. Besides the lowest bed capacity reported in the multi-metal systems, the column operated with nickel ions showed a maximum bed capacity of 12.36 mg/g at a flow rate of 2 mL/min in the 20 cm bed. Furthermore, an extended breakthrough time of 780 min is obtained for 50 mg/L nickel ion solution at a flow rate of 2 mL/min. In addition, the modelling of breakthrough curves using Thomas, Yoon-Nelson and BDST models have shown reasonable fits. In addition, repeated cycles of regeneration studies showed improved efficiency of 65% in the first cycle. More specifically, the alginate validated the selective preferential adsorption of cationic substances over anionic components in the studied column.