Removal of Olefins from Reforming Aromatic Hydrocarbons over Metal-Halide-Modified Acid-Activated Palygorskite

Abstract

A series of acid-activated palygorskite (PAL)-supported metal halides catalysts were synthesized and applied to remove trace olefins from aromatic hydrocarbons. The structural properties and surface acidity of acid-activated PAL were determined by X-ray diffraction (XRD), N2 adsorption/desorption, and NH3-TPD. According to experimental results, the optimum metal halide was CoCl2, and its loading content was 7 wt % with an olefin conversion of 92.1%. Furthermore, the 10%CoCl2/PAL-B21 catalyst before and after the olefin removal reaction was characterized by XRD, FE-SEM, FTIR, N2 adsorption/desorption, NH3-TPD, and XPS. The BET surface area (S BET) of PAL-B21 decreased by 129 m2/g after modification by 10%CoCl2. It was indicated that the interaction between CoCl2 and PAL-B21, the textural properties, and the surface acid sites are all important for the adsorption and conversion of olefins from reforming aromatic hydrocarbons by an alkylation reaction. The low cost, high olefin conversion, and good stability of the CoCl2-modified PAL-B21 catalyst provide industrial application potential for olefin removal from reforming aromatic hydrocarbons.

Selection of suitable bentonite and the influence of various acids on the preparation of a special clay for the removal of trace olefins from aromatics

“…Colloidal inorganic particles with size of less than 2 μm are generally categorized as "clay". This definition is presented regardless of their composition and crystal structure (Guo et al, 2020;Rautureau et al, 2017;Stawinski, 2017). Bentonite is a type of clay with multiple applications in oil, gas, petrochemical, food, pharmaceutical, building and agriculture industries (Abuchenari et al, 2020;Javed et al, 2020;Mannu et al, 2018;Qureshi et al, 2021;Rouhani and Farhadi, 2020;Shakiba et al, 2021).…”

“…Two processes are typically used for the removal of olefins from aromatic streams: (1) clay treating and (2) catalytic hydrotreating (Liu et al, 2017;Guo et al, 2020). In catalytic hydrotreating, olefins are saturated during the hydrogenation reactions on selective hydrogenation catalysts.…”

Optimizing temperature and introducing new process arrangements for elevating clay's longevity based on the known poisons in the separation process of trace olefins from aromatics

“…Production of these components is accompanied by the production of unsaturated aliphatic components that can be harmful to downstream units and poison their catalysts 1‐4 . Clays and hydrotreating catalysts have been widely used for removing these trace aliphatic components from aromatics 5‐8 . Clay treatment is simple but the particular clay used has a limited lifetime.…”

“…[1][2][3][4] Clays and hydrotreating catalysts have been widely used for removing these trace aliphatic components from aromatics. [5][6][7][8] Clay treatment is simple but the particular clay used has a limited lifetime. Hydrotreating catalysts could remove olefins and have a longer service life, but hydrogenation is costly and may lead to loss of aromatics.…”

Highly efficient debromination of 4,4′-dibrominated diphenyl ether by organic palygorskite–supported Pd/Fe nanoparticles

“…The clay minerals commonly used for water treatment are divided into 2:1 and 1:1 structural groups (Ezzatahmadi et al 2017). Palygorskite (PAL) is one type of clays composed of ribbons with speci cally alternating layers, has high speci c surface area and surface groups (Guo et al 2020). These properties are bene cial for PAL to be a catalyst support (Chen et al 2020b).…”