1075-38-3Relevant articles and documents
Influence of n Si/n Al ratio of HY zeolite catalysts on alkylation of toluene with tert-butanol
Wang, Yuanyuan,Song, Hua,Sun, Xinglong,Song, Hua Lin
, p. 2503 - 2507 (2016)
The highly selective synthesis of 4-tert-butyltoluene from toluene and tert-butanol over HY zeolites was performed in liquid phase. The effect of Si/Al ratio (6.3, 7.5, 11, 12) of HY zeolites on the alkylation performance was studied. The catalysts were characterized by SEM, XRD, FT-IR, and NH3-TPD methods. With increase of Si/Al ratio, the conversion of toluene and the selectivity towards 4-tert-butyltoluene increased gradually. HY-12 was found to be more suitable for the tert-butylation of toluene. When the alkylation reaction was conducted at 180°C for 4 h using HY-12 catalyst, the conversion and the selectivity of 4-tertbutyltoluene reached 40.74 and 70.91%, respectively.
Tert-butylation of toluene with tert-butanol over transition metal oxide-modified HBEA zeolite
Han, Yixian,Song, Hua,Wang, Yuanyuan,Sun, Xinglong,Sun, Zhigang
, p. 160 - 165 (2018)
A series of transition metal oxide-modified HBEA (MxOy/HBEA) zeolite catalysts were prepared by the wetness impregnation method, and investigated for the alkylation of toluene with tert-butanol to synthesise 4-tert-butyltoluene (4-TBT). Their physico-chemical properties were characterised by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller and NH3 temperature-programmed desorption methods. MxOy/HBEA zeolite showed higher para-selectivity than parent HBEA due to its improved structural and acidic properties. Though the toluene conversion of MxOy/HBEA catalyst decreased, the 4-TBT selectivity increased significantly at 190 °C after 4 h. The narrowed pores after loading the MxOy prompted an increase in selectivity for 4-TBT by increasing the shape selectivity. In addition, the decrease in strong acid sites increased selectivity for 4-TBT by suppressing further isomerisation of the 4-TBT formed on acid sites. Among all the modified HBEA zeolites, Fe2O3/HBEA exhibited the best catalytic activity and para-selectivity. The factors affecting the reaction over Fe2O3/HBEA have also been investigated extensively.
A process scheme involving transalkylation reactions to prepare o-bromophenol from phenol
Trivedi, Nikhil R.,Chandalia, Sampatraj B.
, p. 5 - 9 (1999)
The bromination of phenol to o-bromophenol was carried out by protecting the para position with a tert-butyl group. The latter group was subsequently transferred to toluene using aluminum chloride as a catalyst. The resulting mixture of p-and m-tert-butyltoluene could be converted back to p-tert-butylphenol by transalkylation of the former with phenol in the presence of Engelhard, F-24. Thus, a process scheme based on transalkylation reactions as the intermediate steps has been proposed to synthesize o-bromophenol from phenol via p-tert-butylphenol. The effect of reaction parameters on overall conversion to and selectivity with respect to the desired product was studied for the transalkylation reactions involved in the process.
Alkylation of Toluene with tert-Butyl Alcohol over Different Zeolites with the Same Si/Al Ratio
Han, Yixian,Song, Hua,Sun, Xinglong,Wang, Wenyi,Wang, Xueqin,Wang, Yuanyuan,Zhang, Jiaojing
, p. 991 - 997 (2020)
Three zeolites (Beta, Mordenite and ZSM-5), with different pore channels but the same Si/Al ratio (25), were applied as catalysts to evaluate the effects of acidity and channel structure on the catalytic activity for toluene butylation at 180°C in an automated high-pressure stainless steel reactor. The same Si/Al ratio of the three zeolites resulted to different catalytic activity, since both acidity and channel structures of zeolites influenced catalytic activity. Zeolite Beta possessing a three-dimensional, 12-ring channel system, the smallest crystal size and larger amount of B acid sites demonstrated the highest toluene conversion (54percent). Mordenite, with 32.7percent toluene conversion, exhibited higher para-selectivity than Beta, which could be explained by the shape-selective catalysis. ZSM-5 with the largest amount of B acid sites presented the lowest catalytic activity, since alkylation can occur only on the surface active sites.
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Schlatter,Clark
, p. 361,362 (1953)
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Preparation of H-mordenite/MCM-48 composite and its catalytic performance in the alkylation of toluene with tert-butanol
Zhou, Zhiwei,Cheng, Fuling,Qin, Juan,Yu, Pengcheng,Xu, Lin,Gu, Zhiqiang,Liu, Xiaoqin,Wu, Wenliang
, p. 1669 - 1675 (2017)
A series of HM/MCM-48 samples with different SiO2/Al2O3 molar ratio were prepared by sol-gel method. The prepared catalysts were characterized by XRD, N2 adsorption-desorption, NH3-TPD, FT-IR, SEM, and TEM techniques, and their catalytic performance was investigated in alkylation of toluene with tert-butanol. The adsorption capacity and the acid sites amount of HM/MCM-48-4 sample prepared by growing MCM-48 on the surface of HM zeolite are much higher than that of their mechanical mixture (HM/MCM-48(4) sample) due to its biporous structure; it shows higher catalytic performance than other HM/MCM-48 samples. The influence of reaction conditions on the catalytic performance of HM/MCM-48-4 zeolite was discussed. Toluene conversion of 41.4% and p-tert-butyltoluene selectivity of 73.5% were obtained at the weight ratio of toluene to HM/MCM-48-4 of 5, reaction temperature of 453 K, reaction time of 5 h and the molar ratio of toluene to tert-butanol of 0.5.
Acyl iodides in the reaction of photochemical Friedel-Crafts acylation
Vlasova,Vlasov,Grigor'eva,Albanov,Voronkov
, p. 294 - 296 (2010)
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Giacomello,Cacace
, p. 1823,1824,1825 (1976)
tert-Butylation of Toluene Catalyzed by Phosphotungstic Acid Supported on HBEA Zeolite
Yuanyuan Wang,Han, Yixian,Sun, Xinglong,Song, Hua
, p. 250 - 254 (2019)
Abstract: The performance of the catalysts prepared by impregnation of phosphotungstic acid (HPW) in HBEA zeolite with different HPW load (HPW(x)/HBEA) was evaluated in alkylation of toluene with tert-butanol with formation of 4-tert-butyltoluene (4-TBT). The obtained results showed that the HPW was highly dispersed on the HBEA support. The specific surface area of HPW(x)/HBEA zeolites decreased along with a decrease in pore volume. The Br?nsted acidity of HPW(x)/HBEA showed a significant increase initially, reaching a maximum at x = 30% and then decreased with further increasing x. The Br?nsted acidity of HPW(30%)/HBEA was 143.0 μmol/g, which is an increase of 69.8% when compared with that found for HBEA (84.2 μmol/g). The HPW(x)/HBEA zeolite with HPW loading of 30% exhibits the best catalytic activity at 180°C after 4 h. Toluene conversion over HPW(30%)/HBEA reached 73.1% with para-selectivity of 80.9%, which much higher than those found for HBEA (activity of 54.0% with para-selectivity of 69.5%). The improved toluene conversion over HPW(x)/HBEA can be attributed to their higher Br?nsted acidity after loading HPW, while the improved selectivity can be attributed to the narrowed pores of HPW(x)/HBEA catalysts.
HIGH CATALYTIC ACTIVITY OF IRON OXIDE FOR BENZYLATION, t-BUTYLATION, AND ACETYLATION OF TOLUENE WITH BENZYL, t-BUTYL, AND ACETYL CHLORIDES
Arata, Kazushi,Hino, Makoto
, p. 1479 - 1480 (1980)
Iron oxides obtained by calcining at 300-500 deg C Fe(NO3)3 or iron hydroxides, precipitated by hydrolyzing FeCl3 and Fe(NO3)3 with ammonia, showed exceedingly high catalytic activities for the title reactions at room temperature.
Flow Friedel–Crafts alkylation of 1-adamantanol with arenes using HO-SAS as an immobilized acid catalyst
Kasakado, Takayoshi,Hyodo, Mamoru,Furuta, Akihiro,Kamardine, Aina,Ryu, Ilhyong,Fukuyama, Takahide
, p. 2253 - 2257 (2020)
In this communication flow Friedel–Crafts alkylation was studied using hydroxy-substituted sulfonic acid-functionalized silica as a catalyst and 1-adamantanol as a model substrate. The reaction of 1-adamantanol (1a) with toluene (2a) proceeded well with 5 min of residence time at 120°C to give good yield of 1-tolyladamantane (3a) as a 1:9 mixture of meta and para isomers. When the flow synthesis was carried out over 2.5 hr of running time, the collected five fractions contain the product 3a in 97–92% yields, suggesting the durability of the catalyst.
Surface Modification of a Supported Pt Catalyst Using Ionic Liquids for Selective Hydrodeoxygenation of Phenols into Arenes under Mild Conditions
Ohta, Hidetoshi,Tobayashi, Kanako,Kuroo, Akihiro,Nakatsuka, Mao,Kobayashi, Hirokazu,Fukuoka, Atsushi,Hamasaka, Go,Uozumi, Yasuhiro,Murayama, Haruno,Tokunaga, Makoto,Hayashi, Minoru
supporting information, p. 14762 - 14766 (2019/11/13)
The selective and efficient removal of oxygenated groups from lignin-derived phenols is a critical challenge to utilize lignin as a source for renewable aromatic chemicals. This report describes how surface modification of a zeolite-supported Pt catalyst using ionic liquids (ILs) remarkably increases selectivity for the hydrodeoxygenation (HDO) of phenols into arenes under mild reaction conditions using atmospheric pressure H2. Unmodified Pt/H-ZSM-5 converts phenols into aliphatic species as the major products along with a slight amount of arenes (10 % selectivity). In contrast, the catalyst modified with an IL, 1-butyl-3-methylimidazolium triflate, keeps up to 76 % selectivity for arenes even at a nearly complete conversion of phenols. The IL on the surface of Pt catalyst may offer the adsorption of phenols in an edge-to-face manner onto the surface, thus accelerating the HDO without the ring hydrogenation.
