Methane reforming to syngas over LaNi x Fe 1x O 3 (0  x  1) mixed-oxide perovskites in the presence of CO 2 and O 2 Hamidreza Arandiyan a , Junhua Li a, *, Lei Ma a , S.M. Hashemnejad b , M.Z. Mirzaei b , Jinghuan Chen a , Huazhen Chang a , Caixia Liu a , Chizhong Wang a , Liang Chen a,c a State Key Joint Laboratory of Environment Simulation and Pollution Control (SKLESPC), School of Environment, Tsinghua University, Beijing 100084, China b Chemical Engineering Department, Iran University of Science and Technology, Tehran, Iran c CPI Yuanda Environmental-Protection Engineering Co., Ltd, Chongqing, China 1. Introduction Hydrogen or mixtures of H 2 , CO and CO 2 (synthesis gas) are used extensively in a wide range of industrial processes [1]. H 2 is predicted to become a major source of energy in the future. It is an important raw material in the chemical and petroleum industries; large quantities are used in the manufacture of NH 3 and CH 3 OH and in a variety of petroleum hydro treatment processes [2,3]. CH 4 can be converted into synthesis gas by steam reforming, CO 2 (DR) reforming or by conversion with O 2 through secondary reforming and POM [4]. Although DR reaction reforming has attracted much attention from both industrial and environmental perspectives, it has not been widely used due to the high level of carbon formation from CH 4 and CO (CH 4 $ C + 2H 2 ; 2CO $ CO 2 + C) [5]. This process offers certain advantages, such as a lower H 2 /CO ratio, and seems to be more suitable for the Oxo and Fischer–Tropsch processes [6]. The POM reaction of CH 4 , expected to afford synthesis gas with a H 2 /CO ratio of 2, makes CH 3 OH synthesis an ideal follow-up process [7]. One of the most serious problems in CO 2 methane reforming is catalysts deactivation by coke. Since the reaction is endothermic, it proceeds at high temperature, thermodynamically favoring coke formation [8]. O 2 addition to CO 2 reforming reaction reduces carbon deposition on the catalyst surface and increases CH 4 conversion [8]. The possibility of uniting a slightly exothermic POM reaction of CH 4 with a highly endothermic reaction of CO 2 reforming has already been proposed and experimentally demon- strated in the literature [9]. Over the past years, many approaches to control these properties of CH 4 reforming to syngas have been extensively investigated. In particular, many mixed-oxide perovskite types have been studied in the CH 4 reforming and emerge as effective catalysts [6,8,10–14]. Therefore, activity and selectivity to syngas, H 2 /CO molar ratio, carbon deposit and also specific surface area, dispersion stability and morphological characteristics of the catalysts have been identified as the important parameters that influence the high-performance for synthesis gas [5,8,13,15]. Numerous materials like Ni, Co, Fe [16,17] and noble metals (Pt, Rh, Pd, Ir) [18,19] have been reported to be active for CH 4 reforming. However, the main problem is quick deactivation of the catalysts due to a strong carbon formation. Some works have studied deactivation [19,20]. Noble metals are reported to be less sensitive to coking as compared to Ni. Some improvements for Ni like bimetallic structure (Ni–Mn; Ni–Fe) [21,22] or addition of alkali earth or rare earth [23] are very important for reducing carbon deposition. The noble metals based catalysts are less sensitive to coking compared to Ni based catalysts. Nevertheless, it is still worthwhile to develop the Ni-based catalysts resistant to the formation of coke because the noble metals are expensive and of limited availability. An alternative is to use Ni and/or Fe based precursors with a well-defined structure, as the perovskite-type Journal of Industrial and Engineering Chemistry 18 (2012) 2103–2114 A R T I C L E I N F O Article history: Received 5 April 2012 Accepted 11 June 2012 Available online 19 June 2012 Keywords: Perovskite catalyst Dry reforming Combined reforming Partial oxidation Syngas A B S T R A C T The perovskite metal-oxides LaNi x Fe 1x O 3 (0  x 1) were synthesized by a sol–gel method and investigated for the DR, POM, and CRM into synthesis gas. The catalysts were characterized by using XRD, BET, CA, SEM, EDS, HR-TEM, EDX and TPR in order to investigate the influence of the preparation parameters and evaluation condition. LaNi 0.4 Fe 0.6 O 3 showed great stability, and fewer carbon deposits were detected on the spent catalyst after 1800 min evaluation on TOS. The effect of GHSV on the catalytic performance was investigated. The results obtained showed the H 2 /CO molar-ratio was around 0.9, 1.7, and 1.1 over different catalysts for DR, POM and CRM, respectively. ß 2012 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved. * Corresponding author. Tel.: +86 10 62771093; fax: +86 10 62771093. E-mail address: lijunhua@tsinghua.edu.cn (J. Li). Contents lists available at SciVerse ScienceDirect Journal of Industrial and Engineering Chemistry jou r n al h o mep ag e: w ww .elsevier .co m /loc ate/jiec 1226-086X/$ – see front matter ß 2012 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.jiec.2012.06.004