Influence of synthesis parameters of mesocellular silica foams doped by nickel on methane reforming by CO2

O Daoura,N El Hassan,M Boutros,P Massiani,F Launay,N Moubayed

doi:10.1051/matecconf/201817103002

Abstract

New catalysts based on Ni(0) dispersed onto mesocellular silica foams (MCF) were prepared for Dry Reforming of Methane (DRM). Different synthesis methods of MCF supports (with and without using NH4F or n-butanol) were tested in order to study the influence of the textural properties of the support on the catalytic performances of the catalysts. In all cases, nickel was incorporated using the double solvents method. The resulting calcined materials were characterized by N2 sorption, X-Ray diffraction (XRD) and transmission electron microscopy. Their reducibility was tested by temperature-programmed reduction (TPR). Interestingly, particularly large specific surfaces, pores diameters and pores volumes were observed when NH4F was added to the synthesis gel (MCF(N) materials). The corresponding Ni-MCF(N) catalysts were shown to be the most attractive among other prepared samples with respect to their performances in DRM.

Highlights

In 1999, siliceous mesocellular foams (MCF) were prepared for the first time by combining self-assembly processes through a (S0H+)(X−I+) pathway used for SBA-15 synthesis and pore swelling with organic molecules [1]
Most of them are of type H2 or H1, which is in agreement with the expected presence, in mesocellular foams, of connected cells and of pores with different shapes
The influence of NH4F has been already described as being related to the mineralizing effect of fluoride ions, giving improved structural organization and higher pore volume [3]

Summary

INTRODUCTION

In 1999, siliceous mesocellular foams (MCF) were prepared for the first time by combining self-assembly processes through a (S0H+)(X−I+) pathway used for SBA-15 synthesis and pore swelling with organic molecules [1]. Four types of MCF materials with different textural properties were synthetized with the aim to select the most convenient supports for DRM catalysts preparation. The latter were obtained after deposition of 5 wt.% Ni using the double solvents method [10]. The catalysts were tested in dry reforming of methane after reduction Their catalytic performances in terms of conversions, products selectivity and stability were analyzed and compared to thermodynamic curves simulated by the HSC program considering or not carbon formation and similar reaction conditions

Catalysts preparation

Catalysts characterisations

N2 physisorption

Reducibility

Catalytic performance in DRM

CONCLUSION