Nanoplastics removal from spiked laundry wastewater using electro-peroxidation process.

Area of Science:

• Environmental Science
• Water Treatment Engineering
• Analytical Chemistry

Background:

• Laundry wastewater (LWW) is a significant source of microplastics and nanoplastics (NPs) entering wastewater treatment plants.
• Limited research exists on the degradation of NPs in LWW, necessitating effective treatment strategies.

Purpose of the Study:

• To investigate the degradation of NPs in commercial LWW using the electro-peroxidation process.
• To analyze the oxidation of organic compounds and optimize process parameters for efficient NP removal.

Main Methods:

• Electro-peroxidation treatment of LWW containing NPs.
• Three-dimensional excitation-emission matrix fluorescence analysis for organic compound identification.
• Response surface methodology (RSM) for process parameter optimization.
• Toxicity assessment using Daphnia magna.

Main Results:

• Complete NP removal achieved in 40 minutes, accelerated by existing chloride ions in LWW.
• Oxidation of humic acid-like, aromatic protein-like, and fulvic acid-like compounds observed at different treatment times.
• Initial TOC concentration negatively impacted NP degradation; optimized conditions minimized energy consumption.
• Treated LWW showed no toxicity to Daphnia magna.

Conclusions:

• Electro-peroxidation is a highly effective method for complete nanoplastic degradation in laundry wastewater.
• The process efficiently removes NPs and associated organic pollutants without generating toxic residues.
• Optimized electro-peroxidation offers a sustainable solution for treating nanoplastics in laundry wastewater.