Conversion of ethanol over metal‐exchanged zeolites

Abstract

The effects of metal exchange between zeolites and alkali metals (Li, Na, K; zeolite Y, ZSM-5, T), alkaline earths (Mg, Ca, Sr, Ba; ZSM-5), transition metals (La, Ce, Cr, Mn, Fe, Co, Ni, Pd, Cu, Zn; ZSM-5) and aluminium (ZSM-5) on the conversion of ethanol were studied, Activities of the catalysts and selectivities for ethene, C3 + olefins, paraffins and arenes strongly depended on the cation, chosen for the modification. Only ethene was formed by alkali exchanged zeolites, the most active being Li-Y. This could be confirmed by a long-term ageing test with Li-Y pellets under semi-industrial conditions. The exchange of ZSM-5 with alkaline earths or transition metals permitted the formation of a wide variety of products, ranging from high ethene to high aromatic yields. A correlation between certain product selectivities and electronegativity was only possible in a rough approximation.

Ethylene Production from Ethanol Over Metal/Phosphorus-Modified ZSM-5 Catalysts

“…Some of the elements are effective to tune the acid sites, so as to raise the ethylene selectivity, inhibit coke formation and enhance the stability of the catalysts. Schulz et al 7 extensively studied the effect of metals on the conversion of ethanol. They used alkali metals (Li, Na, K), alkaline earth metals (Mg, Ca, Sr, Ba) and transition metals (La, Ce, Cr, Mn, Fe, Co, Ni, Pd, Cu, Zn) to modify HZSM-5 zeolites.…”

“…In most cases, ZSM-5 zeolite has been used as the catalyst. [4][5][6][7][8] In order to make green ethylene plants more competitive, researchers have modified ZSM-5 by different methods with mesoporosity 9 10 or various elements. In this short review, we discuss the synthesis, characterization and catalytic performance of metal-or/and phosphorusmodified ZSM-5 catalysts for ethanol transformation to ethylene.…”

Heterobimetallic Zeolite, InV-ZSM-5, Enables Efficient Conversion of Biomass Derived Ethanol to Renewable Hydrocarbons

“…Since then, a large number of reports have appeared in literature on ethanol conversion to hydrocarbons 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 . The reaction temperature for ethanol transformation is generally >350 °C and the pressure ranges from ambient to several atmospheres 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 . The product stream is generally high in C 2 hydrocarbons (e.g., ethylene and ethane), which are not valuable for liquid fuel production or commodity chemical production (separation of pure ethylene is quite expensive from a mixed stream).…”

Metal impregnated catalysts for bioethanol conversion tested by n-hexane cracking

“…The favorable results (C 2 = + C 3 = ) were obtained over Ba-ZSM-5 [11]. The ZSM-5 zeolites modified with transition metals, such as Cu, Zn and Ag increase the yield of aromatics and reduce C 2 = + C 3 = yield in catalytic cracking of C 4 alkanes [3,12]. The effect of rare earth metals on catalytic performance of H-ZSM-5 zeolite was investigated by Wang et al The best total alkenes yield was achived over Ce/H-ZSM-5at 600°C and Nd/H-ZSM-5 at 650°C.…”