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Composites based on chitosan coatings and metal ions are attracting great attention due to their antibacterial properties and biocompatibility. It is known that the presence of chitosan helps to stabilize the growth of metal films or individual nanoparticles during their deposition. In this work chitosan coating obtained from an aqueous carbonic acid solution is applied to fibers of a polypropylene nonwoven membrane. Aqueous carbonic acid solution is a clean and cheap solvent for chitosan that can effectively impregnate a porous polypropylene matrix. Before chitosan deposition, the fibers were pretreated in the presence of peroxycarbonic acid (i.e., in an aqueous hydrogen peroxide solution saturated with pressurized carbon dioxide). Copper ions were then deposited on the chitosan‐coated fibers. It was shown that the presence of a chitosan interlayer can significantly improve adhesion and reduce the aggregation of growing particles, which results in the decoration of the fibers with uniform thin copper‐containing films. The proposed method for creating composite materials can serve as a new approach to antibacterial polymer‐inorganic composites manufacturing.

BACKGROUND Propane dehydrogenation is an alternative way both to produce propylene and to utilize CO2. Because of the high oxygen mobility in cerium‐zirconium oxide (CexZr1‐xO2), it looks promising as a support for the chromium oxide catalysts of propane dehydrogenation with CO2. Supports of CexZr1‐xO2 on mesoporous silica were synthesized in this work to combine the high oxygen mobility of the former and the pore structure of the latter. RESULTS Two applied synthetic approaches resulted in materials with different structure and properties. The wet impregnated catalysts demonstrated a higher activity and selectivity to propylene. At the same time, they had larger pore size distribution maxima (~9 nm) than the samples prepared by the introduction of metals simultaneously with Si‐precursor hydrolysis (~2 nm). For the chromium catalysts with the same support, the catalytic activity decreased with varying chromium loading as follows: 5% Cr > 3% Cr ≈ 7% Cr. For the catalysts with different CexZr1‐xO2 supports and equal chromium loading, the activity decreased with x changing as follows: 0.5 > 0.6 > 0.8 for the samples prepared by wet impregnation, and 0.8 ≈ 0.6 > 0.5 for the other synthetic path. CONCLUSIONS Catalysts were tested in oxidative dehydrogenation of propane with CO2. The wet impregnation approach turned out to be much more promising in terms of catalytic activity and selectivity to propylene in the reaction of propane dehydrogenation with CO2. The selectivity achieved was ≤80% at a 40% conversion. © 2023 Society of Chemical Industry (SCI).

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