A circular economy approach: Reimagining spent pickling sludge for ultra-efficient photocatalytic degradation of bisphenol A and hydrogen evolution under natural sunlight
Source abstract
Abstract
For the first time, spent pickling sludge (SPS), a waste rich in valuable constituents, was integrated with silver nanoparticles to develop an efficient photocatalyst (Ag–SPS) with enhanced photocatalytic activity. The photocatalyst was synthesized via co-precipitation method and exhibited an outstanding Bisphenol A (BPA) degradation efficiency of 93.6%, along with a hydrogen evolution rate of 356 µmolg⁻¹h⁻¹ under natural sunlight. The as-synthesized photocatalyst was characterized using UV-DRS, FESEM-EDX, HRTEM, XRD, XPS, ESR, VSM, confirming the successful fabrication of Ag-SPS. The incorporation of Ag nanoparticles induced a red-shift, leading to improved electron–hole separation and enhanced visible-light absorption. Moreover, the influence of key operational parameters, including BPA concentration, pH, and catalyst loading, was optimized using RSM-BBD. As a result, the Ag–SPS displayed excellent recyclability, with only 6.2 % loss after 5 cycles. Besides, ion studies performed using the ICP–OES technique confirmed that the released ion concentrations remained well below environmental safety limits. Importantly, magnetic nature of the photocatalyst allows for easy recovery and reuse, making it a cost-effective and sustainable. Overall, this work aligns with the concept of circular economy by upcycling industrial waste (SPS) into a sunlight-driven photocatalyst for water remediation and hydrogen production, promoting resource recovery and sustainability.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Advanced Photocatalysis Techniques · Advanced oxidation water treatment · TiO2 Photocatalysis and Solar Cells
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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