Selective ring opening of methylcyclopentane over Pt/γ-Al2O3, Ir/γ-Al2O3 and Pt-Ir/γ-Al2O3 catalysts with hydrogen at atmospheric pressure

Nickel Boosts Ring‐Opening Activity of Iridium

“…The peak at 120 8C may represent the reduction of highly dispersed surface Ir species, which agrees with other results. [6] The major peak at 200 8C indicates the reduction of IrO 2 , which is formed during the calcination period before the TPR, [41,42] whereas the peak centred at 272 8C resembles documented results for Ir/g-Al 2 O 3 calcined at 420 8C, attributed to the reduction of O-rich complexes. [41] The TPR spectrum of Ni/g-Al 2 O 3 reveals a major peak at 219 8C (reduction of NiO phase), [43] followed by two smaller peaks at 258 and 316 8C.…”

“…[2] Since the 1970s, RO of cyclic compounds has been studied extensively using the Pt-group supported catalysts. [1,[3][4][5][6][7] The RO of naphthenic rings relies on a metal-driven chemistry and among the different metals studied, Ir is the most selective and active ring-opening catalyst. [1,8,9] The RO of several cyclic molecules such as methylcyclopentane, ethylcyclopentane, methylcyclohexane, dimethylcyclopentane, dimethylcyclohexane, indane, decalin, perhydroindane and trimethylcyclohexane has been studied using Ir-supported catalysts.…”

“…[1,8,9] The RO of several cyclic molecules such as methylcyclopentane, ethylcyclopentane, methylcyclohexane, dimethylcyclopentane, dimethylcyclohexane, indane, decalin, perhydroindane and trimethylcyclohexane has been studied using Ir-supported catalysts. [1,2,[5][6][7][10][11][12][13][14] Mechanism of the metal-catalysed RO of naphthenic rings depends on the nature of the metal, its particle size, and support effects. [8,15] Iridium is reported to operate mostly through the dicarbene mechanism, implying perpendicular adsorption of two carbon atoms of a naphthenic ring, which results in the cleavage of unsubstituted secondary-secondary carbon atom bonds.…”

Ring Enlargement of Methylcyclopentane over Pt/(HZSM-48+pseudoboehmite) Catalysts

“…In the petrochemical process, a large amount of methylcyclopentane (MCP) is produced as a by-product, and the process of producing benzene from MCP has been steadily becoming important [2][3][4][5][6][7]. The reforming of MCP is known to be a combination of three types of competing reactions over the noble metal/solid acid catalysts as follows [2,[8][9][10][11][12][13]: Conversion to cyclohexane and benzene by ring enlargement (RE), conversion to n-hexane and iso-hexane via ring opening (RO), and generation of light molecules that contain less than 6 carbon atoms by cracking. Product selectivity is known to be related to the nature of the catalyst and the operating conditions [14].…”

“…Amorphous oxide, zeolite, mesoporous material, and hybrid supports composed of amorphous oxide and zeolite have been studied as general supports for MCP reforming catalysts. Al 2 O 3 , SiO 2 , and ZrO 2 -SiO 2 have been used as amorphous supports [12,13,[15][16][17][18]; and Y zeolite, HZSM-5, mordenite, beta zeolite, L zeolite, and AlPO 4 have been applied as zeolite supports [1,4,5,8,9,13]. Recently, studies on mesoporous materials, such as SBA-15 and MCF-17, have been reported [2,3].…”