Effect of high-temperature treatment on the activity of montmorillonite pillared by alumina in the conversion of 1,2,4-trimethylbenzene

Selective reduction of NO with NH3 over pillared clays modified with transition metals

“…The NH 3 desorption spectrum obtained for the Mt-Al montmorillonite is spread in the range of 130-500 • C and consist of at least two unresolved maxima centered at 170 and 280 • C, respectively. The low-temperature peak can be assigned to NH 3 desorption from weak acidic Brønsted sites localized on the montmorillonite layers, while high-temperature maximum is related to ammonia desorption from acidic centers present on the metal oxide pillars [6]. Modification of the alumina pillared clay with small amount of copper slightly decreased intensity of high-temperature desorption peak.…”

Preparation and characterization of novel composite AlCr-pillared clays and preliminary investigation for benzene adsorption

“…The acidity of PILC originates from the montmorillonite layer, from the pillaring agent, or from an interaction between both of them. The pillars are the main source of Lewis type of acidity, while a weak Brønsted acidity arises from structural hydroxyl groups of the montmorillonite layers (Matsuda et al, 1988). Considering the porous structure, pH of pillaring agent and, the adsorption amount of benzene, it suggests that AlCr-PILC(2.5;24;140) with large pore volume, large basal spacing and suitable amount and strength of acidity are the best material for the adsorption of benzene.…”

Recent Advances in the Control and Characterization of the Porous Structure of Pillared Clay Catalysts

“…Selective reduction of NOx has been the reaction of environmental interest for which PILCs have been most widely used (102, 103, 106, 109, 111 -115, 117, 132, 157 -164), other reactions, as complete oxidation of VOCs or of CFCs (104, 105, 119, 135, 136, 145, 146, 165 -168) and wet hydrogen peroxide catalytic oxidation of waste (108, 169 -189), have also been studied. Benzylation of aromatic compounds Fe-PILC [35] Benzylation of aromatic compounds Al-,FeAl-,AlCr-AlTi-PILC 60 -908C, aromatic: benzyl ¼ 10 chloride ¼ 10 [32] Benzene and benzyl chloride/ diphenylmethane Fe-,Al-,Zn-PILC 808C [36] Benzene or toluene and benzyl chloride/ diphenylmethane Al-,Cr-,Fe-PILC 258C [37] Toluene and methanol/xylenes Al-, AlGa-PILC 300 -4008C [38] Toluene and methanol/xylenes Zr-PILC [39] Toluene and methanol/xylenes Al-PILC 4008C, Toluene: methanol ¼ 2:1 [40] Toluene and methanol/xylenes Al-PILC 4008C [41] Toluene and methanol/xylenes Al-PILC 3508C, Toluene: methanol ¼ 2:1 [42] Catechol (CAT) and tert-butyl alcohol Si-PILC, SiAl-PILC 1358C; TBA:CAT ¼ 2:1; 68-77% conversion [43] (TBA)/butyl 4-tert-butylcatechol propene and biphenyl/polyalkylated products Al-PILC 2508C [44,45] Ethanol and benzene/ethylbenzene Ti-PILC 300 -4508C; Ethanol: benzene ¼ 1 and 6 [46] Benzene; chlorobenzene; anisole and benzylchloride AlFe-PILC, AlTi-PILC, AlCr-PILC 708C; Aromatic/ benzyl chloride ¼ 15 [32] 1,2,4-Trimethylbenzene and methanol/ 1,2,4,5-tetramethylbenzene Al-PILC 2808C, Methanol:1,2,4-TMB ¼ 1 [47,48] Benzene and long chain a-olefins (C 10 -C 13 ) Zr-PILC 150-1808C, Benzene: olefin ¼ 15:1 and 5:1 [49] 156 Downloaded by [University of Wyoming Libraries] at 06: 15 18 September 2013 Phenol and methanol/cresols and xylenols,methylanisols…”