Catalytic Activity of Copper Oxide Impregnated HZSM‐5 in Methanol Conversion to Liquid Hydrocarbons

Abstract

M ethanol obtained from coal and natural gas can be used as a raw material for synthesis of methanol. Methanol is used as a raw material for the production of olefins and other hydrocarbons using zeolite catalysts. Zeolites such as HZSM-5 have attracted many researchers to obtain yield of gasoline range hydrocarbons. Its nature and extent of reaction depend on acid strength, acid site density, catalyst topology, temperature, pressure, space velocity and other process conditions (Alkawaldeh et al., 2003;Cañizares et al., 1998;Marchi and Froment, 1993;Mikkelsen and Kolboe, 1999). The influence of metal/metal oxide incorporation over the surface of zeolite enhanced the methanol conversion and hydrocarbon yield (Zaidi and Pant, 2004;Al-Jarallah et al., 1997;Freeman et al., 2002;Kang, 2000;Zhu et al., 2000). The catalytic conversion of methanol to gasoline range hydrocarbon over CuO, ZnO doped HZSM-5 catalyst increases the hydrocarbon yield as compared to unmodified HZSM-5 (Zaidi and Pant, 2004). It has been reported that the long life of zeolite catalysts for methanol conversion to gasoline (MTG) was due to the variation in physicochemical properties of ZnO over CuO/HZSM-5 (Stöcker, 1999;Haw et al., 2003). Arstad et al. (2004) studied the chemistry and mechanism of reaction of methanol to hydrocarbon at various reaction parameters. In a subsequent study, various techniques have been used to characterize zeolites catalyst and to study the impact of catalytic action with different type to zeolites catalysts (Donk et al., 2003; A number of CuO/HZSM-5 catalysts have been studied in a small scale fixed bed reactor for the conversion of methanol to gasoline range hydrocarbons at 673 K and at one atmospheric pressure. All the catalysts were prepared by wet impregnation technique. The copper oxide loading over HZSM-5 (Si/Al=45) catalyst was studied in the range of 0 to 9 wt%. XRD, surface area analyzer, metal trace analyzer, SEM techniques and TGA were used to characterize the catalysts. Incorporation of CuO onto HZSM-5 zeolite significantly increased conversion and liquid hydrocarbon product yields. The major liquid products of the reactions were ethyl benzene, toluene, xylene, isopropyl benzene, ethyl toluene, trimethyl benzene and tetramethyl benzene. The maximum methanol conversion and hydrocarbon product yield was obtained at a copper oxide loading of 7 wt%. Effect of run time on conversion and product distribution was also investigated to compare the performance of these catalysts and coke on the catalyst was determined. Effect of space-time and temperature on methanol conversion and products yield with 7 wt% CuO/HZSM-5 has also been investigated and analyzed qualitatively.On a étudié plusieurs catalyseurs de CuO/HZSM-5 dans un réacteur à lit fixe de petite échelle pour la conversion méthanol en hydrocarbures de type carburants à 673 K et à pression atmosphérique. Tous les catalyseurs ont été préparés par la technique d'imprégnation humide. La charge en oxyde de cuivre sur le catalyseur HZSM-5 (Si/Al=45) a été étud...

Hydrothermal synthesis of nanocrystalline H[Fe, Al]ZSM-5 zeolites for conversion of methanol to gasoline

“…Reducing the aromatic content in the produced fuels is very important to http address the global more strict environmental regulations. In the past few years, more continuous researches were reported on the modification of HZSM-5 by various metal oxide composites, such as CuO [21], ZnO/CuO [8] and Ga 2 O 3 [22,23], as well as acid or alkali treatment [2,24] in MTG process. Most studies revealed that the acidic properties and mesopore formation of ZSM-5 catalysts were well altered, and the diffusion properties of the pore channels were improved.…”

Conversion of methanol to aromatics over ZSM-5/11 intergrowth Zeolites and bimetallic Zn-Cu-ZSM-5/11 and Ga-Ag-ZSM-5/11 catalysts prepared with direct synthesis method

“…Also, agglomeration of some metal particles on the outer surface of zeolite can cause similar effects. 46,47 According to Figure 2(a), the N 2 adsorption-desorption isotherms of all samples exhibit an incremental slope in lower relative pressures which could be attributed to the typed I isotherm with H 4 -shaped hysteresis loops indicating the presence of micropores in the structure of zeolites. But at pressures of 0.45 \ p/p0 \ 0.9, the hysteresis loops of the modified samples are more distinct than ZSM-5/11 zeolite, indicating mesoporosity increases after incorporation of metals.…”

Challenges & Opportunities on Catalytic Conversion of Glycerol to Value Added Chemicals

“…This is crucial to increase the lifetime and efficiency of the catalyst. The research outcomes pointed out that direct glycerol thermochemical reaction is technologically feasible but hindered by catalyst coking that will poison the catalyst [77] and ineffective catalyst regeneration [62,78]. Table 3 explains the catalytic conversion of glycerol to different chemicals which are beneficial to us.…”