Carboxymethyl cellulose nanocomposite beads as super-efficient catalyst for the reduction of organic and inorganic pollutants

Carboxymethyl cellulose/copper oxide-nickel oxide (CMC/CuO-NiO) nanocomposite beads were prepared by facile, simple and environmentally friendlymethod. Initially, CuO-NiOwas prepared and applied for the catalytic reduction of 4-nitrophenol (4-NP). The results showed that CuO-NiO demonstrate high catalytic activity toward the reduction of 4-NP to 4-aminophenol (4-AP) with a rate constant of 2.97 x 10(-2) s(-1). Further, CuO-NiO were well-dispersed in the polymeric matrix of carboxymethyl cellulose to prepare CMC/CuO-NiO beads. CMC/CuO-NiO nanocomposite beads were also applied to catalyze the reduction of potassium ferrocyanide (K3Fe (CN)(6)), 4-NP, Congo red (CR) and Eosin yellow(EY) in the presence of sodiumborohydride. Experimental data indicated that CMC/CuO-NiO nanocomposite has higher catalytic activity and high rate constant compared to CuO-NiO. The rate constant found to be 6.88 x 10(-2), 6.27 x 10(-2), 1.89 x 10(-2) and 2.43 x 10(-2) for K3Fe(CN)(6), 4-NP, CR and EY, respectively, using 5 mg CMC/CuO-NiO beads. FE-SEM, EDX, FTER, XRD and XPS were used to characterize the nanocomposites. CMC/CuO-NiO beads catalytically reduced up to 95-99% of K3Fe(CN)(6), 4-NP, CR and EY within 40, 60, 120 and 120 s. CMC/CuO-NiO beadswere found more selective for the reduction of 4-NP. The catalytic reduction performance of CMC/CuO-NiO beadswas optimized by studying the influence of different parameters on the catalytic reduction of 4-NP. Hence, the effective and super catalytic performance toward the reduction of different organic and inorganic pollutants makes CMC/CuO-NiO beads a smart material and suitable for numerous scientific and industrial applications and may be used as an alternative to high-cost commercial catalysts. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

CMC/CuO-NiO nanocomposite beads were prepared using a facile and environmentally friendly method, exhibiting high catalytic activity in the reduction of various organic and inorganic pollutants. Characterization of the beads was conducted using various techniques and their catalytic performance was found to be superior to CuO-NiO alone.