Innovative non-thermal plasma treated NiMo-ADM zeolite catalyst for dry reforming of methane

Abstract

In this study, a simple and effective Non-thermal Plasma (NTP) treatment was used to produce Ni-Mo catalysts, with Attapulgite (ATP)-Derived Mobil Five Instructure (MFI) zeolite (ADM) as the support. The catalytic activity and resistance to carbon deposition in the DRM reaction were separately investigated in terms of the effects of adding Mo and the NTP treatment. Structural characterization confirmed the successful integration of Ni and Mo species within the attapulgite-derived MFI framework. Catalysts containing Mo exhibited significantly higher initial catalytic activity compared to Mo-free ones. H₂-TPR results demonstrated that the addition of Mo strengthened the metal-support interactions, and NTP treatment increased the proportion of metals in the catalyst that could function as active sites. CO_2-TPD analysis showed that Mo addition enhanced the ratio of weakly basic and medium basic sites, and this tendency was further reinforced by NTP treatment. Under continuous operation for 100h, the plasma-treated Ni7Mo1-ADM-P catalyst exhibited exceptional stability with CH₄ conversion rates maintained at 90.4 %. At the GHSV of 90,000 mL·g_cat⁻¹·h⁻¹, the CH₄ and CO₂ deactivation rates were merely 0.011 % h⁻¹ and 0.008 % h⁻¹, respectively. After 100 h of reaction, the characteristic peaks of MFI molecular sieves could still be detected in the used catalysts, reflecting their high stability. Additionally, Ni7Mo1-ADM-P had a higher degree of graphitization defects, making its carbon deposits easier to remove. This study could offer a reference for further enhancing catalyst performance through NTP treatment.