CO2 reforming of methane over Zr-promoted Ni/SBA-15 catalyst : effect of zirconium loading

In the present time, increased concerns on anthropogenic greenhouse gas emissions and abundance of natural gas resources have renewed interest in the CO2 (dry) reforming process as an alternative to steam reforming for synthesis gas production from natural gas. The catalytic performance of catalyst is considered the most crucial field of study in CO2 reforming of methane. Various researches were conducted in order to optimize the conversion and minimize the deactivation rate of catalyst. In this research, the effect of Zirconium promoter on the Ni/SBA-15 catalyst at normal reaction temperature of CO2 reforming of methane had been carried out using a continuous-flow fixed-bed quartz reactor. A series of Zirconium promoted Ni/SBA-15 catalyst with different Zirconium contents (1, 3, 5, 7 wt %) prepared using modified sol-gel method. In addition, the catalyst samples with different Zirconium loadings characterized using BET surface measurement, Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) and Thermal Gravimetric Analysis (TGA). The synthesized Zr/Ni/SBA-15 catalyst tested for CO2 reforming of methane. This reaction is considered to be a great alternative to produce synthesis gas since it utilizes two abundant greenhouse gases. CO2 reforming of methane yields low hydrogen to carbon monoxide (H2/CO) ratio, which is desirable for many industrial synthesis processes. On the other hand, Zirconium promoted Nickel species enhances the formation of active center for the reaction. As a result, the promoted catalyst with 1wt% of Zr perform with optimum catalytic activity and producing higher amount of H2 at reaction temperature of 800oC compared to others. Zirconium species is well dispersed and promote the Nickel to be confined to the pores of SBA-15. The wall of SBA-15 limited the sintering of the Ni components. Thus, the Nickel species not undergone sintering as it is well embedded to SBA-15 which can withstand higher temperature

Structural effect of Ni/SBA-15 by Zr promoter for H2 production via methane dry reforming

5 wt% of Ni/SBA-15 supported with numerous Zr loading (1–7 wt%) were produced using sol-gel technique at 60 °C. The influence of Zr promoter on the physiochemical properties of Ni/SBA-15 catalysts for methane dry reforming were examined in a fixed-bed reactor at 800 °C. Analytical characterizations including XRD, BET, FTIR, N2 adsorption desorption, TEM and TGA were conducted to study the physiochemical properties of Zr/Ni/SBA-15 catalysts for the sake of identification of the amount of coke deposition formed on the spent catalyst. Increasing the amount of Zr loading from 1 to 7 wt% supported on Ni/SBA-15 reduced the catalyst's surface area as was proven from the physiochemical properties of Zr/Ni/SBA-15 catalyst. The catalytic activity test revealed that the optimum Zr loading was 1 wt% at which CH4 and CO2 conversions were 87.07% and 4.01%, meanwhile H2:CO ratios was 0.42. This result was owing to the existence of the Zr species in promoting a good dispersion of Nickel (Ni) active sites on the catalyst surface as affirmed from XRD and FTIR results. The latest discovery indicates that promotion of 1 wt% Zr onto Ni/SBA-15 can prompt excellent catalytic performance in CRM

Syngas production via CO2 reforming of CH4 over Zr-Ni/SBA-15

In the present study, the effect of Zirconium (Zr) loading (1-7wt %) as promoter on the properties of Ni/SBA-15 catalyst for production of syngas by CO2 reforming of CH4 were studied. Zirconium promoted Ni/SBA-15 catalyst was prepared using one pot sol-gel method as described in the literature [1]. The physiochemical properties of Zr-Ni/SBA-15 catalysts were characterized using XRD, BET and FTIR meanwhile the catalytic performances of the of the catalyst was carried out in a stainless steel fixed bed reactor at 800°C, atmospheric pressure and CO2/CH4 feed ratio of 1/1. The ordered mesoporous structure of SBA-15 was proven by N2 adsorption desorption isotherms. The surface area and pore volume of catalyst were decreased with the increase of Zr loading as ZrO2 particles were occupied in SBA-15 frameworks and thus destroyed SBA-15 structured [2]. ZrO2 peak of 1Zr-Ni/SBA-15 was not detected in XRD result (Fig. 1) indicates to well dispersion of the Zr species on the SBA-15 surfaces [3]. The catalytic activity test revealed that the optimum Zr loading was at 1 wt% with CH4 conversion, CO2 conversion and H2/CO ratio were 87.07%, 74.01%, and 0.42, respectively as illustrated in Fig. 2. This was due to the well dispersion of Zr that promote the Nickel (Ni) species to confine in the SBA-15 pores as proven by XRD and FTIR analysis. All catalysts showed a good stability up 900oC with less than 5 % weight loss as analyzed by TGA. The addition of 1wt % of Zr enhance the Ni dispersion which create a proper active site for CH4 and CO2 accessibility and also reduce carbon formation