Dzhyga G. Bentonites modified with Pd(II) and Cu(II) compounds in the reactions of carbon monoxide and sulfur dioxide oxidation and ozone decomposition

The dissertation work has accomplished some actual theoretical and practical tasks: the properties of bentonites from three different Ukrainian deposits (Gorbskyi (N-Bent(G)), Kirovogradskyi (N-Bent(K)), and Dashukovskyi (N-Bent(D)) were compared and the latter, i.e. N-Bent(D), has been used in order to demonstrate some methods of purposeful regulation of its physicochemical and structural-adsorption parameters. These methods included calcination at 300 C (300-Bent(D)), boiling in distilled water (H2O-Bent(D)), boiling in 1 M HNO3 over different time periods (τ) (1H-Bent(D)-τ) or at different HNO3 concentrations (from 0.25 to 6.0 mol/L) and τ = 1 h (Х ̅Н-Bent(D)-1), and intercalation of aluminum polyhydroxy cation, Al13 (Al-PILC). The most efficient methods are boiling in nitric acid and intercalation of Al13. Catalytic activities of the К2PdCl4 Cu(NO3)2-KBr/N-Bent compositions in the reaction of CO oxidation have been found to depend on the bentonite origin and the method of its modification. The following orders of activity of all Cu(II)-Pd(II)/ compositions compared to the Cu(II)-Pd(II)/N-Bent(D) composition have been determined: N-Bent(D) << N-Bent(K) < N-Bent(G); N-Bent(D) ≈ 300-Bent(D) << Н2О-Bent(D); N-Bent(D) << 1Н-Bent(D)-0.5 > 1Н-Bent(D)-1 > 1Н-Bent(D)-3 ≈ 1Н-Bent(D)-4 ≈ 1Н-Bent(D)-6; N-Bent(D) << 0.25Н-Bent(D)-1 < 0.5Н-Bent(D)-1 < 1Н-Bent(D)-1 < 3Н-Bent(D)-1 <6Н-Bent(D)-1. It has been found that only Pd(II)-Cu(II)/6Н-Bent(D)-1 with the given com-ponent ratio provides sufficiently high CO conversion of 96 % and, consequently, CO concentration at the reactor outlet below 20 mg/m3, MPC for working area air. The physicochemical model permitting selection of natural and modified bentonites as supports for Pd(II) and Cu(II) coordination compounds catalytically active in the reactions of carbon monoxide (CO) and sulfur dioxide (SO2) oxidation and ozone (O3) decom-position at ambient temperatures has been developed. A new method for preparing a catalyst for low-temperature carbon monoxide oxida-tion KNO-CO/6H-Bent-1 has been suggested. The catalyst was recommended for applica-tion in “Platan” type cartridge half-mask respirators (TU U 28.2-01530125-038:2015). A draft documentation describing a catalyst for O3 decomposition, KNO-O3/N-Bent, has been developed.