Sono-dispersion of bimetallic Ni-Co over zeolite Y used in conversion of greenhouse gases CH4/CO2 to high valued syngas

Bio Gas Reforming (BGR) process is an interesting route for the removal of greenhouses gases. The presented research deals with nanocatalyst development by sonochemical method for bio gas reforming. The main aim of this study is achieving the optimized composition of Ni-Co bimetallic catalyst over zeolite Y. The zeolite Y and Ni-Co/Y nanocatalysts were characterized by XRD, FESEM, EDX, BET and FTIR techniques. The XRD patterns displayed the formation of appropriate phases. EDX analysis revealed the presence of all elements and uniform dispersion of active metal phase. Also, the FESEM images showed that Ni7Co3Y catalyst had smaller particles size and more limited distribution than Ni3Co7Y catalyst. Based on BET analysis results, when the composition of nickel and cobalt changed, catalysts had different surface area. Actually, changing in Co and Ni composition had the reverse effect on specific surface area. Moreover, the formations of desired functional groups were proved by FTIR characterization. The reforming reactions were carried out at GHSV = 24 l/g h, P = 1 atm, CH4/CO2 = 1 and at the temperature range of 550-850 degrees C. The activity tests displayed that Ni7Co3/Y activity was higher than zeolite Y and Ni3Co7/Y catalyst at all temperatures and the activity Ni7Co3/Y catalyst remained stable during 10 h. Furthermore, the proposed reaction mechanism showed that there are six major reaction channels for NiCo/Y catalyst in biogas reforming process. (C) 2015 Elsevier B.V. All rights reserved.