The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. The functional hearing loss induced by ethylbenzene and the histological patterns seen are very similar to the effects of toluene or styrene, namely, midfrequency hearing loss and selective outer cell damage (Figure 12). did use a different strain of rats of a younger age than did Fechter et al. Although the production of polyalkylated benzene can be suppressed by this mode of operation, a transalkylation step is still required. %PDF-1.3 Production of ethylbenzene is on the order of hundreds of metric tons per year in the United States alone (ethylbenzene toxicological profile draft USPHS, ATSDR). Ethylbenzene has low to moderate potential for adsorption to soil or sediment (predicted log Koc = 2.71). Styrene is primarily a synthetic chemical that is used extensively in the manufacture of plastics, rubber, and resins. � #\ Information about how to use the RightsLink permission system can be found at not otherwise permitted to reproduce, republish, redistribute, or sell any Supporting Information The conversion of light alkanes to olefins is crucial to the chemical industry. The contributions of ethylbenzene exposure from the production and uses of styrene are relatively very small. Ethylbenzene (EB) is the key intermediate in the production of styrene, which is a monomer produced in very large volumes. endobj Perego and Ingallini reported that in 2002, approximately 75% of the EB in the world was produced by zeolite-based processes, indicating that the remaining amount is still obtained by using Friedel–Crafts catalysts (298). Vogt, ... Bert M. Weckhuysen, in, Carbon Dioxide Utilization for Global Sustainability, Spillover and Mobility of Species on Solid Surfaces. BTEX compounds are volatile, so the HS–SPME mode can be used successfully in many applications. M.L. Separation and Purification Technology 2019 , 228 , 115760. Concentrations of 200 ppm ethyl benzene are known to be irritating to the eyes of humans. In addition to this intended use, ethylbenzene is present at low concentrations in fuels and may be found in automobile exhaust. <>/Filter/FlateDecode/Length 8657>> The reactor section is designed according to [1]. The combined solvent exposure did not disrupt pure tone auditory thresholds or yield a loss of hair cells–a finding that on its surface appears inconsistent with the Cappaert reports. Health effects from exposure to styrene may involve the central nervous system and include complaints of … The x-ray structure of the EBDH from Aromatoleum aromaticum has been solved to 1.88-Å resolution and shows the active site Mo ion to be located at the bottom of a 25-Å tunnel that is dominantly lined with nonpolar amino acid residues.32 The Mo ion is coordinated by two pyranopterin–dithiolenes and a monodentate aspartate. The supported catalysts originally proposed (BF3/Al2O3 and SPA) are not active for transalkylation and therefore did not play a major role in commercial application (298). The quest for improved catalytic performance for this conversion is motivated by current drawbacks including: expensive noble metal catalysts, poor conversion, low selectivity, and fast decay of efficiency. Fresh ethylbenzene is mixed with a recycle stream and vaporized. The transalkylation step is an important feature in all commercial EB production processes. Created for consumers, educators, the media, and industry employees, is a reliable, one-stop source of information on styrene and styrene-based products. A preheated mixture of ethylbenzene vapor and superheated steam passed over one of several possible dehydrogenation catalysts preheated to 620–640 °C crack 30–40% of the ethylbenzene in one pass (Eq. The spiltover oxygen from CeO2 was suggested to promote the oxidationof BTEX on Pt/CeO2 catalyst. The formation of styrene on the polynaphthoquinone was observed even at 170 °C. The process combines the dehydrogenation of ethane and ethylbenzene in one unit and integrates the processes for preparing ethylene, ethylbenzene and styrene. No evolution of hydrogen was found in the dehydrogenation reaction. from the ACS website, either in whole or in part, in either machine-readable form or any other form “Ethylbenzene (CAS 100-41-4) is a low molecular weight, highly flammable liquid with moderate volatility and an aromatic odor. Ethylbenzene’s health hazards include transient CNS [central nervous system] depression at high levels, lung aspiration, irritation, and ototoxicity. An acetate oxygen atom that derives from the buffer provides the sixth ligand bound to molybdenum and the coordination geometry is described as distorted trigonal prismatic. The ODE with CO2 was reported previously in refs. In air, ethylbenzene undergoes photodegradation (indirect photolysis) with a half-life in air of 2 days. The styrene synthesis from ethylbenzene over polynaphthoquinone was investigated in the range of temperature 170–270 °C. An improved version of the Lummus/UOP process called EBOne comprises a two-reactor system in which the initial alkylation catalyst is likely zeolite beta (297,298). The sensitivity of the SPME method using PDMS coating for these compounds is very high, allowing mid- to low ppt determinations in water. The exposure levels were 660 ppm ethylbenzene for 6 h day−1 for either 5 or 10 days. Xie, ... Y.-D. Xu, in Studies in Surface Science and Catalysis, 2001. Inhalation or ingestion of high concentrations has led to central nervous system (CNS) depression with death attributed to depression of the respiratory center. A few ppm of 4-t-butylcatechol inhibitor is added to the purified product after which it is ready to be shipped. Ethylbenzene (EB) is the key intermediate in the production of styrene, which is a monomer produced in very large volumes. system. Towson, MD 21286 1999, 2001, 2002). In the present paper, we report on a new route for the production of EB by combining the alkylation of C6H6 with the ODE using CO2 as an oxidant. The alkylation of benzene with ethylene produces … Cappaert et al. Moreover, there is a possibility that combined exposure to toluene along with ethylbenzene might have altered the rate of solvent metabolism. In the rat exposed to ethyl benzene (b), two of the three OHCs have disappeared and the remaining OHC has a shrunken balloon-like appearance but still adheres to the reticular lamina. The reaction can be carried out at a temperature lower than that required for the C2H6 pyrolysis. Virtually all of the ethylbenzene produced is destined for styrene production, ultimately leading to polystyrene and other polymers. stream The Pt/CeO2 catalyst exhibited much higher activity in comparison to the Pt/Al2O3 catalyst. Dong-Keun Lee, ... Soo-Gon Kim, in Studies in Surface Science and Catalysis, 2001. Catalyst oxidation of BTEX was investigated in the presence of Pt/CeO2 and Pt/Al2O3 catalysts. Clicking on the donut icon will load a page at with additional details about the score and the social media presence for the given article. Ethylbenzene Science. S.-J. Electronic Supporting Information files are available without a subscription to ACS Web Editions. Gangfeng Ouyang, in Handbook of Solid Phase Microextraction, 2012, BTEX has been the most investigated group of organic compounds of environmental interest. Gagnaire and Langlais (2005) also demonstrated that ethylbenzene given to rats by daily gavage for 2 weeks could produce profound loss of outer hair cells. Industrial yield (selectively) of styrene from ethylbenzene is about 90%. 400 E Joppa Road, Suite 108 endstream Vogt, ... Bert M. Weckhuysen, in Advances in Catalysis, 2015. Ethylbenzene is commercially produced from benzene and ethylene in industrial plants, and a minor amount is isolated by purifying petroleum by-product streams. General method of STM, selective thermal catalytic conversion of ethylbenzene to styrene, STM images, in situ UV irradiation experiment, results (data) of adsorption and photoreaction of ethylbenzene and p-diethylbenzene, theoretical calculations, dehydrogenation of p-diethylbenzene (PDF). Many workers, including those who make boats, tubs, and showers, are potentially exposed to styrene. Zeolites were applied in research on new EB processes from the mid-1960s, but a commercial process based on zeolites did not mature until 1980. Ethylbenzene is converted to styrene at high selectivity in a multistage process in which ethylbenzene is oxidized to ethylbenzene hydroperoxide which is reacted with ethylene or propylene to produce a mixture of 1-phenylethanol and acetophenone which are converted to styrene. It is used primarily as an intermediate for styrene production and is also a natural component of petroleum products and incomplete combustion of natural substances, and is present in tobacco smoke. And while rats are sensitive to ethylbenzene’s ototoxicity, guinea pigs are not (Cappaert et al. Styrene who is also known as ethylbenzene,vinybenzene and phenylethene is an organic compound with the chemical formula C 6 H 5 CH=CH 2. endobj Copyright © 2020 Elsevier B.V. or its licensors or contributors. It is also known as vinylbenzene, ethenylbenzene, cinnamene, or phenylethylene. [/PDF/ImageB/ImageC/ImageI/Text] Results of Two Analytical Methods for BTEX Applied to Four Non-Spiked Municipal Sludge Samples. Ethylbenzene (Figure 8a) is a high-production aromatic hydrocarbon used principally in the production of styrene. Fechter et al. Original catalysts were Friedel–Crafts-type catalysts AlCl3–HCl and BF3/Al2O3, and silica-SPA. Light micrographs showing the organ of Corti as observed in the lower part of the middle turn of the rat cochlea. Conventionally, the production of EB is based on the alkylation of C6H6 with pure C2H4. While ethylbenzene conversion over Pt/Al2O3 was 89% at 240°C, complete conversion of ethylbenzene was achieved in the presence of Pt/CeO2. The alkylation catalyst in this process is very likely also zeolite beta (298). Furthermore, EBDH can also hydroxylate a range of alkylaromatic and alkyl-heterocyclic compounds.