Enhanced photo catalytic degradation of polyacrylamide microplastics: a comparative evaluation with microalgae treatment
摘要
Polyacrylamide microplastic is an emerging pollutant and is reported to be a threat to many aquatic and terrestrial species. In the current study, polyacrylamide microplastic was detected (up to 1 mg/L) and quantified using UV-spectroscopy with an excellent interference resistance, repeatability, and strong quantitative analysis capability (R2 > 0.99). The photo-catalytic and biological degradation efficiency was tested using zinc oxide and microalgae, respectively. As PAM (Polyacrylamide Microplastic) is utilized extensively due to its well-known stable chemical properties, understanding how it can be removed and degraded is essential. This study analyzes the impact of 100, 250, and 500 mg/L of polyacrylamide exposure on the photocatalyst and the process of biodegradation using Acutodesmus obliquus. It was observed that polyacrylamide was degraded by 40% in 48 h, and 90% in 20 days using the microalgal species, while photocatalysis with ZnO showed significantly higher efficiency of 97% in less than 48 h, with COD reduction of 95%, effectively eliminating the presence of any toxic intermediate. ZnO photocatalysis is more effective than biological treatment, offering rapid degradation, higher removal efficiency, and scalability using energy-efficient LED lighting. This study underscores the potential of photocatalysis as a robust and cost-effective method for the remediation of PAM-contaminated waters.