Prospective Catalytic Structured Converters for NH3-SCR of NOx from Biogas Stationary Engines: In Situ Template-Free Synthesis of ZSM-5 Cu Exchanged Catalysts on Steel Carriers

Abstract

The main objective of this study is to develop highly active catalyst and its preparation method that would meet the requirements of steel carriers for shortchannel structured converters for NO x abatement from stationary biogas engines. The in situ synthesis was applied to deposit a series of Cu-exchanged MFI zeolite (ZSM-5) on kanthal sheets. The samples differ in preparation conditions: organic template assisted and template-free synthesis, Si/Al ratio and catalyst carrier pretreatment (calcined vs. non-calcined). Dip-coating method was used as a reference to compare loading efficiency. In order to evaluate preparation quality and purity of resulting structure the samples were examined by XRD and SEM/EDS at various stages of preparation. For the assessment of mechanical endurance of the deposited catalyst layers the ultrasonication method was used. The results demonstrated high depositing efficiency of the in situ synthesis as well as high activity and selectivity of the Cu-exchanged MFI samples prepared without costly organic template.

DeNOx Abatement Modelling over Sonically Prepared Copper USY and ZSM5 Structured Catalysts

“…According to our previous studies [18,19], the SEM analysis revealed that the layer thickness is ca. 20 µm for catalysts deposited on the steel support.…”

“…In the literature, the deposition of the zeolites onto the metallic supports is performed via dip-coating of the support in the zeolite suspension or zeolite gel [7]. However, our recent development on zeolite deposition revealed that the deposition of the zeolites using dipcoating from zeolite suspension does not provide the efficient support coverage and, what is more important, does not have the efficient mechanical resistance [18]. In recent study [18], we reported the comparison of the deposition of the MFI zeolite onto the metallic supports using dip-coating, in situ deposition and in situ deposition on non-calcined support.…”

“…However, our recent development on zeolite deposition revealed that the deposition of the zeolites using dipcoating from zeolite suspension does not provide the efficient support coverage and, what is more important, does not have the efficient mechanical resistance [18]. In recent study [18], we reported the comparison of the deposition of the MFI zeolite onto the metallic supports using dip-coating, in situ deposition and in situ deposition on non-calcined support. The mechanical strength of the deposited zeolite was measured by the application of ultrasound test, where the supports with the deposited zeolite material were placed in an ultrasound bath and irradiated with 35 kHz for 1 h in acetone solution.…”

“…In this study, the extraordinary activity of catalysts prepared using sonochemical preparation route was proposed. In the literature, the activity of USY and ZSM-5 catalyst was previously discussed [18,19,22,23]. However, over the cited literature reference, the copper/zeolite catalysts were prepared by classical ion-exchange method.…”

“…In the literature reports, the short channel structures as well as metallic foams have recently been reported as having a great potential as catalyst supports for gas exhaust abatement [12][13][14][15][16]. In our previous works [12,17,18], we reported the superior activity of ion-exchanged Cu/SSZ-13 and Cu/ZSM-5 zeolite catalysts deposited on kanthal plates and foams. In the literature, the deposition of the zeolites onto the metallic supports is performed via dip-coating of the support in the zeolite suspension or zeolite gel [7].…”