Preparation and characterization of active Ni-supported catalyst for syngas production

Abstract

A new type of Ni-based catalyst, using geopolymer as support was prepared and characterized using scanning electron microscopy (SEM), temperature programmed reduction (TPR), N2 adsorption–desorption, nuclear magnetic resonance (NMR) and transmission electron microscopy (TEM).The catalytic performance of Ni-geopolymer catalyst was investigated in steam reforming (SR), partial oxidation (POX) and autothermal steam reforming (ATR) of ethanol to syngas, at the temperature of 700°C. The gaseous mixture flow was adjusted (in terms of molar ratio) for each of the three reactions: steam reforming, steam to carbon (S/C)=2.5; partial oxidation, oxygen/carbon (O/C)=0.5; and autothermal reforming, S/C=2.5 and (O/C)=0.5.Ni species supported on the geopolymer surface resulted to be highly active, with a complete ethanol conversion and with the largest amount of hydrogen (∼70mol%) being produced under the SR conditions. In the spent catalysts, after POX reaction, some coke formation was observed by SEM and thermogravimetric (TG) analyses. The results showed that geopolymer would be a promising, low cost and environmental friendly material for reforming reactions of ethanol.