Chitosan@Carboxymethylcellulose/CuO-Co(2)O(3) Nanoadsorbent as a Super Catalyst for the Removal of Water Pollutants

In this work, an efficient nanocatalyst was developed based on nanoadsorbent beads. Herein, carboxymethyl cellulose–copper oxide-cobalt oxide nanocomposite beads (CMC/CuO-Co(2)O(3)) crosslinked by using AlCl(3) were successfully prepared. The beads were then coated with chitosan (Cs), Cs@CMC/CuO-Co(2)O(3.) The prepared beads, CMC/CuO-Co(2)O(3) and Cs@CMC/CuO-Co(2)O(3), were utilized as adsorbents for heavy metal ions (Ni, Fe, Ag and Zn). By using CMC/CuO-Co(2)O(3) and Cs@CMC/CuO-Co(2)O(3), the distribution coefficients (K(d)) for Ni, Fe, Ag and Zn were (41.166 and 6173.6 mLg(−1)), (136.3 and 1500 mLg(−1)), (20,739.1 and 1941.1 mLg(−1)) and (86.9 and 2333.3 mLg(−1)), respectively. Thus, Ni was highly adsorbed by Cs@CMC/CuO-Co(2)O(3) beads. The metal ion adsorbed on the beads were converted into nanoparticles by treating with reducing agent (NaBH(4)) and named Ni/Cs@CMC/CuO-Co(2)O(3). Further, the prepared nanoparticles-decorated beads (Ni/Cs@CMC/CuO-Co(2)O(3)) were utilized as nanocatalysts for the reduction of organic and inorganic pollutants (4-nitophenol, MO, EY dyes and potassium ferricyanide K(3)[Fe(CN)(6)]) in the presence of NaBH(4). Among all catalysts, Ni/Cs@CMC/CuO-Co(2)O(3) had the highest catalytic activity toward MO, EY and K(3)[Fe(CN)(6)], removing up to 98% in 2.0 min, 90 % in 6.0 min and 91% in 6.0 min, respectively. The reduction rate constants of MO, EY, 4-NP and K(3)[Fe(CN)(6)] were 1.06 × 10(−1), 4.58 × 10(−3), 4.26 × 10(−3) and 5.1 × 10(−3) s(−1), respectively. Additionally, the catalytic activity of the Ni/Cs@CMC/CuO-Co(2)O(3) beads was effectively optimized. The stability and recyclability of the beads were tested up to five times for the catalytic reduction of MO, EY and K(3)[Fe(CN)(6)]. It was confirmed that the designed nanocomposite beads are ecofriendly and efficient with high strength and stability as catalysts for the reduction of organic and inorganic pollutants.