Combining Carbon Fibers with Ni/γ–Al2O3 Used for Syngas Production: Part A: Preparation and Evaluation of Complex Carrier Catalysts

Abstract

To promote the adsorption and activation of carbon dioxide in the dry reforming of methane (DRM), Ni and Al2O3 were coprecipitated on activated carbon fibers (ACF). Various characterization methods were adopted in order to investigate the surface characteristics of different catalysts. Chemisorption characterization results, such as H2-temperature programmed reduction (H2-TPR), H2-temperature programmed desorption (H2-TPD), and CO2-temperature programmed desorption (CO2-TPD) illustrated that ACF in a nickel-based catalyst could enhance the basic sites and improve the metal dispersion on a catalyst surface, which is beneficial for the adsorption and activation of feed gas. The coprecipitated coating on ACF proved by scanning electron microscope (SEM) can prevent the carbon of ACF from participating in the reaction, while retain good surface properties of carbon fibers. X-ray diffraction (XRD) patterns illustrated that the ACF in a nickel-based catalyst could decrease the crystallite size of the spinel NiAl2O4, which is beneficial for methane reforming. In addition, the Fourier transform infrared spectroscopy (FTIR) of different catalysts revealed that the added ACF could provide abundant functional groups on the surface, which could be the intermediate product of DRM, and effectively promote the reaction. Different to the catalyst supported on single alumina, the performance evaluation and stability test proved that the catalyst added with ACF exhibited a better catalytic performance especially for CO2 conversion. Moreover, based on the characterization results as well as some related literature, the dry reforming mechanism over optimum catalyst was derived.

Catalytic co‐pyrolysis of packaging plastic and wood waste to achieve H 2 rich syngas

“…In the case of AC catalyst supporter, one peak can be recognized at 660 C. Contrary, two adequately separated peaks are seen in case of metal loaded catalysts: one small peak at around 280 C and the main at 550 C. Yu et al demonstrate comparable results for Ni on AC fibers catalyst. 42 The intensities follow the Ni content at both peaks; however, a little temperature shift can be observed. The temperature of the maximum rate of reduction is decreased by increase the Ni content.…”

Recent Progresses in the Design and Fabrication of Highly Efficient Ni-Based Catalysts With Advanced Catalytic Activity and Enhanced Anti-coke Performance Toward CO2 Reforming of Methane

“…Wei et al (2020) demonstrated that the carbon fiber with layered silicate could improve the sintering performance of the Ni-based catalyst at high temperature of CRM because carbon fiber favored the decomposition of CO 2 . Yu et al (2018) prepared Ni-based catalysts with different ratios of Al 2 O 3 /ACF for CRM reaction. They found that the incorporation of the activated carbon fibers (ACF) to the Ni/γ-Al 2 O 3 /ACF catalyst was beneficial to improvement of the CRM catalytic activity.…”

Intrinsic Kinetics Study of Biogas Methanation Coupling with Water Gas Shift over Re-Promoted Ni Bifunctional Catalysts

“…The conventional routes to employ biomass are diverse, including combustion to produce heat, pyrolysis to extract bio-oil, and gasification to obtain biogas [3]. Particularly under the background of rapid urbanization in China, converting biomass to biogas by means of gasification is of both social and economic significance, as it not only can supply centralized gas for urban residents, but also could largely reduce the dependence on fossil fuels [4,5].…”

“…Due to the issues of high CO content and low heating value, the biogas needs to be upgraded before it is finally transported to downstream users via pipelines. Water gas shift (Equation 1)is an efficient technical method to reduce the CO content in biogas, and the methanation reaction (Equation (2)) is able to increase the heating value by producing CH 4 . As a result, the above two reactions are frequently applied in the upgrading process of biogas into urban gas [6][7][8].…”

“…Yuan et al prepared the SiO 2 supported Ni-Ru bimetallic catalyst, which exhibited an outstanding synergistic effect on methanation and water gas shift. The CH 4 and CO 2 selectivity under the condition of 593 K and 1 MPa could reach around 80% and 10%, respectively [10]. Mei combined Co and Ru together to obtain Co-Ru bimetallic nanoparticles for water gas shift.…”