Comparative Investigation on Synthesis, Characterization, Dye Decoloration and Remediation of Nutrients from Industrial Effluents by TiO2 and ZnO Metallic Nanoparticles
Description
The present pilot-scale study was focused on synthesis and characterization of metallic nanoparticles (TiO2, ZnO), optimization of metallic nanoparticles at variation of pH, concentration, contact time and agitation time, (rpm), decolorization of dyes (Methylene Blue-MB, Rhodamine-B: RMB) using TiO2 & ZnO under two different radiations (UV, Natural Sunlight), and remediation of nutrients (Phosphate, Sulphate, Nitrate, Iron, Chromium, Total Hardness, Ca-Hardness, Mg-Hardness, Chloride) from four industrial effluents (Berger Paints Industry-BPI, Vallabh Vidyanagar Sewage Treatment Plant-VSTP, Petlad Sewage Treatment Plant-PSTP, Organic Chemical Indutry-OCI) using synthesized metallic nanoparticles under UV & Sunlight, Central Gujarat, India. Optimization gradient (TiO2) was 25 ml, 50 ppm Conc., 8 pH, 10 ppm TiO2, 1 hour, 72.10% removal; 100 rpm, 70.30% removal; 8 hours, 74.90% removal; 50 ppm TiO2, 78.32% removal, and in case of ZnO; optimization gradient was 25 ml, 50 ppm Conc., 8 pH, 10 ppm ZnO, 1 hour, 63.26% removal; 100 rpm, 63.66% removal; 8 hours, 68.28% removal; 50 ppm ZnO, 74.50% removal. Overall, maximum optimization was achieved with TiO2 compared to ZnO. Dye decoloration gradient (MB) was TiO2 (1 ppm), UV (6 hours, 100%), TiO2 (3 ppm), UV (6 hours, 99.66%), TiO2 (5 ppm), UV (6 hours, 98.40%), and in case of RMB, dye decoloration gradient was TiO2 (1 ppm), UV (6 hours, 99.70%), TiO2 (3 ppm), UV (6 hours, 99.30%), TiO2 (5 ppm), UV (6 hours, 88.20%). Maximum dye decoloration was observed in MB compared to RMB. In BPI effluent, Iron was found to be maximally removed (98.32%) by TiO2 under UV after 6 hours, and 95.25% by ZnO with UV after 6 hours; VSTP effluent: Chromium, 98.46%, TiO2, UV, 6 hours, and Chloride, 95.00%, ZnO, UV, 6 hours; PSTP effluent: Chromium, 94.59%, TiO2, UV, 6 hours, and Mg-hardness, 95.50%, ZnO, UV, 6 hours; OCI effluent: Chromium, 97.72%, TiO2, UV, 6 hours, and Nitrate, 94.31%, ZnO, UV, 6 hours. Overall, TiO2 was observed in remediating Sulphate (80.51%, UV) compared to ZnO (Sulphate, 75.18%). The findings of the present study clearly reveals that metallic nanoparticle TiO2 has been observed in resourceful dye discoloration of MB very efficiently compared to RMB, and remediation of nutrients more proficiently from polluted industrial effluents compared to ZnO. The outcomes of this pilot study can be proved as benchmark, concrete and conclusive remarks for dye decoloration as well as nutrients remediation of natural and anthropogenic industrial effluents using synthesized metallic nanoparticles at lab and industrial scales regionally, nationally and world over.