Mechanical, Structural and Catalytic Properties of the Co-Al-O Coatings

Abstract

Co-Al-O type nanocrystalline catalytic coatings of 30 μm thickness were formed by the activated thermo-chemical
condensate deposition (AT-CCD) method on the strip steel 0C-404 of 40 μm thickness. After thermal treatment, the
following investigations of the system “coating-substrate” were made: adhesion, resistance to acids (H2SO4, HNO3 and
H3PO4 – concentration 60 %) and alkali NaOH. Phase composition, size of crystallites, morphology and elemental
composition of the surface were analysed.
Given catalyst (large block) was assessed at temperature up to 600 °C, high gas flows Qgas = 2.75 l/min and small
oxygen amount O2 = 0.15 %. The catalyst starts to operate at T = 150 °C – 200 °C. Maximum conversion for CO = 80 %
and NOx = 100 % were obtained at 450 °C.
Given catalyst (small block) was assessed at temperatures up to 275 °C, low gas flows Qgas = 0.50 l/min and large
oxygen amount O2 = 20.0 %. The catalyst (CO oxidation) started to operate at T = 25 °C, maximum conversion (100 %)
was obtained at 240 °C.