Abstract
Nitroaromatic compounds (NACs) are growing worldwide concern for their toxicity, driving a search for efficient removal methods. In the present investigation, we have described the sustainable development of recyclable polymer-based clay metal-oxide nanocomposite beads. First, the copper oxide nanoparticles (CuO NPs) are immobilized on the surface of aminoclay (AC), and then the stabilized CuO NPs are deposited on sodium alginate (Alg). In order to test the broad applicability of the produced AC@CuO-Alg beads, toxic 4-nitrophenol (4-NP) was reduced to 4-aminophenol (4-AP) using the reducing agent NaBH4 in less than 24 minutes with 96 % conversion in water with a rate constant (k) of 0.128 min-1. The catalyst displayed superior stability and good catalytic activity. The catalyst showed strong recyclability, recovering 76% of the catalyst and converting 4-NP to 4-AP with constant activity across four cycles. Furthermore, the reduction of various toxic nitroaromatic compounds such as 4-nitroaniline (4-NA) and nitrobenzene (NB) was investigated in an array of organic solvents including water by varying the temperature. The catalyst demonstrated excellent stability and good catalytic activity in water which is a green solvent in comparison to the organic solvents viz. methanol, ethanol and acetonitrile. The catalyst’s properties offer new opportunities for heterogeneous catalysis research.
