Innovative 3D-manufacture of structured copper supports post-coated with catalytic material for CO2 methanation

Abstract

Innovative copper 3D-structures were manufactured by additive manufacturing (AM) technique for application as catalytic supports in CO2 methanation. The influence of the sintering temperature, atmosphere and technique (pulsed electrical current sintering (PEC) vs conventional furnace sintering) was investigated. The microstructural evolution of the support was analysed by low-temperature N2 adsorption, scanning electron microscopy (SEM), optical microscopy (OM) and X-ray diffraction (XRD). It was found that reducing sintering atmosphere decreases the inner porosity of the fibres of the structures till ca. 0.1%. Fibres of the sample sintered by PEC were found to be as dense as the ones processed with conventional sintering, however PEC sintering results in the unwanted surface oxidation. Adhesion strength of the catalytic coating on copper supports was benchmarked with stainless steel supports. Both Ni/alumina coated structured supports and conventional packed-bed catalyst were examined in CO2 conversion to methane. No deactivation was observed after 80 h time-on-stream in the presence of 10 ppm H2S. The addition of 10 ppm H2S to the stream did not significantly change the structured catalyst performance, although negligible carbon deposition on the catalyst surface was observed.