Effect of the synthesis conditions of Ni/Al2O3 catalysts on the biogas decomposition to produce H2-rich gas and carbon nanofibers

Abstract

The utilization of biogas as carbon source for the co-production of filamentous-like materials and syngas is proposed. Catalysts with different Ni:Al molar ratios, Al 2 O 3 supports and preparation methods were synthesized. The suitability of the catalysts was analyzed considering activity, stability and carbon yield. Catalysts showed a good performance and similar results according to syngas compositions were obtained.However, some differences related to stability over time and carbon yields were detected. TPR analysis and TEM micrographs of the fresh catalysts revealed the presence of two different Ni particles: large Ni particles with low metal support interaction (MSI) that favoured the formation of encapsulating carbon and small Ni particles inserted in the Al 2 O 3 structure with a greater MSI that lead to NCs formation.Generally both kinds of Ni particles were observed in all catalysts, however their relative abundance was dramatically affected by the Al 2 O 3 employed, the preparation method and the Ni:Al molar ratio.

SINTESIS DE CATALIZADORES EN BASE A Ni-Cu POR IMPREGNACIÓN PARA LA OBTENCIÓN DE NANOFIBRAS DE CARBONO POR DEPOSICIÓN CATALÍTICA DEL METANO

“…The peaks at 37,2°, 43,2°, 62,8° and 75,3° in the XRD have been assigned to NiO by Jiménez 15 and De Llobet et al 16 , in accordance with the letter (JCPDS 78-0645) for a mixture of nickel and copper oxide. Lee et al 17 attribute the 43,3° and 62,8° peaks to the crystalline structure of (Ni-Cu)O.…”

Comparative Studies of Non‐noble Metal Modified Mesoporous M‐Ni‐CaO‐ZrO2 (M = Fe, Co, Cu) Catalysts for Simulated Biogas Dry Reforming

“…Although the main component of biogas is methane (50%-70%), it always contains a large portion of carbon dioxide (30%-50%) which decreases the energy efficiency and produces ignition problems in their direct utilization in gas or fuel engines. [1,2] However, from the view point of biogas reforming, high CO 2 concentration (up to 50%) makes it a perfect choice to be used as feedstock via the dry reforming process (CH 4 ＋CO 2 → 2H 2 ＋2CO, ΔH 298 ＝247.3 kJ•mol 1 ) to suitable syngas (H 2 and CO) that can be used for hydrogen production, [3] solid oxide fuel cell [4] or for hydrocarbons synthesis via Fischer-Tropsch process. [5] The development of suitable metal catalyst is considered to be one of the main problems need to be solved.…”

High Recovery of Selenium from Kesterite‐Based Photovoltaic Cells

“…Thermal oxidation in tubular furnace was performed in vertical configuration . The quartz reactor inside the furnace has 759 mm length, 15 mm inner diameter and 18 mm external diameter.…”