Efficiency of ozonation process with calcium peroxide in removing heavy metals (Pb, Cu, Zn, Ni, Cd) from aqueous solutions

Abstract

Heavy metal ions have deadly effects on all forms of life, and through the disposal of industrial wastewater, they enter water resources and, eventually, the food chain. Advanced oxidation processes can remove hazardous and non-degradable organic pollutants in aqueous solutions. Variables examined were initial concentrations of calcium peroxide and heavy metals, contact time, pH, and ozonation rate. Maximum removal rate of heavy metals by ozonation with calcium peroxide under optimal conditions (contact time = 90 min, pH = 3, heavy metal concentration = 25 mg/L, calcium peroxide concentration = 0.025 mg/L and ozonation rate = 1 g/min) in synthetic and real samples were respectively 89.8% and 64.6% for Pb, 92.1% and 73.9% for Cu, 90.4% and 69.7% for Ni, 86.9% and 59.1% for Cd, and 93.4% and 78.8% for Zn. Maximum COD removal rates in synthetic and real samples were 88.1% and 69.9%, respectively. Removal rates of heavy metals and COD under optimal conditions on wastewater from the Isfahan electroplating industry and steel company were determined. The use of the ozonation process with calcium peroxide can be recommended as a good, coefficient method for the removal of heavy metals in wastewater treatment.

Separation of copper ions by nanocomposites using adsorption process

“…The most common hazardous heavy metals affecting human and environment are Sb, Cr, Cd, Cu, Pb, and Hg, etc. 1 , 3 , 5 , 6 . Copper can be found mainly as divalent cation in aqueous solutions and the most widely used metal ion in different industries, include metal finishing, paint, pigment industries, fertilizer, wood manufacturing and electrical 1 , 7 .…”

Hybrid UV/COP advanced oxidation process using ZnO as a catalyst immobilized on a stone surface for degradation of acid red 18 dye

“…In the catalytic ozonation systems, the nature of generated oxidants depend on the catalyst used type [46] . For example, interaction between ozone and CaO 2 could generate superoxide which enhance the ozone transformation to OH − [47] .…”

Paper mill wastewater treatment by Fe2+ and heat‐activated persulfate oxidation: Process modeling and optimization

“…In many studies, recalcitrant and toxic chemicals have been removed from water or wastewater by AOPs 2,6‐8 or using nanoparticles 9‐11 . AOPs may be applied before biological treatment to ensure the degradability of biorefractory organic substances 1 or as a polishing step after conventional treatment methods of industrial wastewater 12 .…”