Improved Catalytic Activity of Composite Beads Calcium Alginate@MIL-101@Fe3O4 Towards Reduction Toxic Organic Dyes.

The defiance of this study was to explore the potential of alginate/MIL-101 beads containing Fe₃O₄ nanoparticles as a catalyst for the reduction of dyes. The Fe₃O₄@MIL-101 magnetic composite was obtained by the mechanical method and then encapsulated using calcium alginate (CA) as a crosslinked matrix. The Fe₃O₄(X)@MIL-101/CA composites beads at different content (X) of Fe₃O₄ nanoparticles were evaluated for the catalytic reduction of methylene blue (MB) and orange G (OG). The aerogel beads have completed the MB dye reduction after 7 min with a rate constant of 0.962 min^–1. This strong activity is assigned to the synergistic effect between Cr containing MIL-101 the Fe₃O₄ particles and the hydrides formed on the catalyst surface. The obtained optimal conditions of MB dye reduction were used for the reduction of OG dye in simple and binary system.The best catalyst M(1)@MIL-101/CA showed a high affinity via MB dye in a binary system. Then was easily recovered by an external magnetic field and reused for 4 cycles. On the other hand, the time of the catalytic activity clearly increased in its 4th reuse in the reduction of MB dye but did not affect the efficiency of catalytic reduction. [ABSTRACT FROM AUTHOR]