Functionalising Pinus roxburghii Biochar with Mg–Fe-LDH for Effective Organic Pollutant Mitigation in Wastewater

Biochar, a carbon-enriched material, has been introduced as robust sorbent for the removal of wide array of pollutants. Recently, Biochar functionalized with metals or metal hydroxide composites has gained attention as low-cost, sustainable materials. Layered double hydroxides (LDHs) and biochar interact synergistically to produce composites with significantly improved specific surface area, structural heterogenicity, surface functional groups, stability and adsorptive properties. In this study, composites constructed out on Mg–Fe LDHs supported by biochar (BC) derived from Pinus roxburghii (chir pine) waste are synthesised. Pinus roxburghii biochar (PR-BC-500) was produced at 500 ℃ under inert conditions and used to synthesize biochar incorporated LDH nanostructures (PR-LDH-500) hydrothermally. Nanocomposites were characterized by XRD, FTIR, BET, Raman, Zeta potential, UV, PL, SEM and EDS techniques. The SEM results display the ideal distribution of LDH particles on the surface of biochar, increasing surface area and occupying pores, confirming composite formation. Photocatalytic outcomes demonstrated that the BC particles integrated into the LDH structure demonstrated strong photocatalytic performance as prepared. 93.4% of Methylene Blue was degraded through photocatalytic degradation in the active participation of PR-LDH-500 nanocomposites, whereas PR-BC-500 degraded only 76.8%. The optimal conditions for methylene blue degradation using PR-LDH-500 and PR-BC-500 photocatalysts were achieved at a catalyst dosage of 50 mg, with a maximum degradation of 94% at pH 12 after 240 min of UV irradiation. According to the results, PR-LDH-500 has outstanding feasibility as a durable and inexpensive adsorbent for the purifying dye-tainted aqueous ecosystems.