Effect of plasma-chemical and thermal treatment in oxygen on the activity of Na_3ZrM(PO_4)_3 phosphates (M = Zn, Co, Cu) in the transformation of butanol-2

摘要

The catalytic properties of plasma-chemically and thermally treated triple zirconium orthophosphates Na_3ZrM(PO_4)_3 (M = Zn, Co, Cu) in the transformation of butanol-2 are studied. X-ray photoelectron spectroscopy data indicate that the surface composition of the samples differs from the stoichiometry, especially in the case of M = Cu. The partial reduction of copper ions occurs during plasma-chemical treatment (PCT), while the amount of Cu on the surface of Na_3ZrCu(PO_4)_3 diminishes. Treatment in an oxygen glow discharge results in a 3-8 times greater yield of the alcohol dehydrogenation product, methyl ethyl ketone. The energy of the alcohol's bonds with the surface is reduced and the dehydration active sites become fully inactivated. In contrast, thermal treatment (TT) results in an increase in the activity of Na_3ZrM(PO_4)_3 in the dehydration of butanol-2.