Development and Performance Evaluation of a Carbon Nanotube-Supported Copper Oxide Wire Mesh Catalytic Converter for Carbon Monoxide Reduction

The high cost of platinum-group-metal catalysts continues to drive the search for affordable alternatives for automotive emission control. This study presents the development of a carbon-nanotube-supported copper oxide (CuO) wire-mesh catalytic converter designed to enhance carbon monoxide (CO) emission reduction while reducing dependence on conventional noble-metal catalyst systems. Unlike conventional ceramic honeycomb converters, the proposed design employs a stainless-steel wire-mesh substrate coated with multi-walled carbon nanotubes (MWCNTs) that serve as a washcoat support for the CuO catalyst. The catalytic converter was fabricated through surface treatment, dip coating of an MWCNT–polyvinyl alcohol (PVA) washcoat, CuO catalyst deposition, and thermal calcination before installation in a customized converter housing. Performance was experimentally evaluated using a single-cylinder gasoline engine under four operating configurations: without a catalytic converter, with a commercial metallic catalytic converter, with a CuO-coated wire-mesh converter, and with the developed MWCNT–CuO wire-mesh converter. Carbon monoxide emissions were continuously monitored over a 30 min operating period using a flue-gas analyzer. The fabricated converter maintained coating integrity throughout calcination and engine operation without observable delamination. Relative to the CuO-coated wire-mesh converter, which achieved 65.68% CO conversion efficiency, the MWCNT-supported catalyst showed a 3.12% relative improvement, increasing the conversion efficiency to 67.73%. One-way ANOVA indicated statistically significant differences in CO emissions among the four configurations (F = 681.49, p < 0.05). The MWCNT-supported configuration also reduced emission fluctuations, with the standard deviation decreasing by approximately 61%, indicating improved operational stability. Although a formal economic analysis was not conducted, the use of non-noble-metal materials suggests potential cost advantages relative to conventional noble-metal-based converters. The commercial catalytic converter exhibited the highest overall performance, achieving 99.53% CO conversion efficiency. Overall, the findings demonstrate the feasibility of durable, nanostructured, non-noble-metal catalytic converters for automotive emission-control applications.