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Shape Selective Catalysis
Published in Subhash Bhatia, Zeolite Catalysis: Principles and Applications, 2020
Until recently, all commercial plants that make ethylbenzene via alkylation of benzene with ethylene employed Friedel craft-type catalysts, mostly aluminum chloride. A solid acid catalyst avoids pollution problems, reduces catalyst consumption, and eliminates the need for corrosion-resistant materials of construction.
Chemicals from Aromatic Hydrocarbons
Published in James G. Speight, Handbook of Petrochemical Processes, 2019
Ethylbenzene (C6H5CH2CH3) is a highly flammable, colorless liquid which is an important chemical as an intermediate in the production of styrene, the precursor to polystyrene. It is one of the C8 aromatic constituents of the products (reformates) of reforming processes. Ethylbenzene can be obtained by intensive fractionation of the aromatic extract but most of the ethylbenzene is obtained by the alkylation of benzene with ethylene. C6H6+CH2=CH2→C6H5CH2CH3
Organic Pollutants
Published in Paul Mac Berthouex, Linfield C. Brown, Chemical Processes for Pollution Prevention and Control, 2017
Paul Mac Berthouex, Linfield C. Brown
Benzene has an impressive history as a commercial chemical, but its use has diminished because it is a carcinogen. The annual U.S. production of benzene is almost 7 billion metric tons, and the world production is seven times this amount. Today about 80% of benzene is consumed in the production of ethylbenzene, cumene, and cyclohexane. Ethylbenzene is a precursor to styrene, which is used to make polymers and plastics. Cumene is converted to phenol for resins and adhesives. Cyclohexane is used in the manufacture of nylon. Smaller amounts of benzene are used to make some types of rubbers, lubricants, dyes, detergents, drugs, explosives, and pesticides. Benzene is a natural constituent of crude oil and an important component of gasoline. Gasoline in the U.S. cannot contain more than 1.3% benzene by volume.
Area under the blood concentration-time curve (AUC) of ethylbenzene concentration in rats: relationship to inhalation and oral administration route-dose
Published in Journal of Environmental Science and Health, Part A, 2020
Makoto Take, Tomoki Takeda, Hiroaki Ishikawa, Michiharu Matsumoto, Kasuke Nagano, Shoji Fukushima
Ethylbenzene (EB) is almost exclusively used as an intermediate for the manufacture of styrene.[1–3] The styrene used in paint solvents can include up to 15% EB. EB is also found in crude oil and products such as kerosene and gasoline that are refined from crude oil.[3] The Ministry of the Environment, Government of Japan has reported that EB is present in outdoor and indoor air, and community drinking water.[3] The primary route of exposure of humans to EB is ingestion, inhalation, and dermal absorption.
Probabilistic health risk assessment of occupational exposure to BTEX in a paint manufacturing plant using Monte-Carlo simulation
Published in Human and Ecological Risk Assessment: An International Journal, 2023
Maedeh Hosseinzadeh, Rasoul Hemmatjo, Zahra Moutab Sahihazar, Sadjad Galvani, Mohammad Hajaghazadeh
Table 5 and Figure 5 present the results of the cancer risk simulation for benzene and ethylbenzene inhalation exposure in various workshops of the paint manufacturing plant. In cancer risk classifications, a lifetime cancer risk (LTCR) greater than 1E-4 is considered a "definite risk," while an LTCR between 1E-4 and 1E-5 is categorized as a "probable risk," and an LTCR between 1E-5 and 1E-6 is classified as a "possible risk" (Khoshakhlagh and Morais 2022). According to Table 5, the mean cancer risk of benzene ranged from 2.37E-4 in the plastic container production workshop to 6.20E-3 in the spray paint production workshop, indicating a definite cancer risk for all workers. Similarly, the cancer risks of ethylbenzene exceeded the 1E-4 level in all workshops, indicating a definite cancer risk. Given the high concentration of ethylbenzene in the putty production and thinner packing workshops, the cancer risk of ethylbenzene were 5.07E-2 and 7.34E-2, respectively, for these workshops. In other words, exposure to ethylbenzene alone could result in the development of 507 and 734 additional cases of cancer per 10,000 putty production workers and thinner packing workers, respectively. According to Ghobakhloo et al. the high levels of ethylbenzene compounds in the paint industry are attributed to the presence of ethylbenzene impurity in solvents and excessive use of thinner for surface cleaning (Ghobakhloo et al. 2023). Mo et al. found that in the paint and coatings industry, toluene, m/p-xylene, and ethylbenzene accounted for more than 70% of total VOC emissions. Ethylbenzene has been linked to unacceptable cancer risks in a variety of industries, including spray paints (9.71E-4), wooden furniture manufacturing (1.75E-5), municipal solid waste (1.71E-6), electronic waste dismantling processes (6.2E-3), rubber footwear industry (>1E-4), and oil refineries (6.091E-3). (Mo et al. 2021). From a health perspective, it is essential to prioritize the removal of ethylbenzene during paint manufacturing.
Room-temperature BTEX sensing characterization of nanostructured ZnO thin films
Published in Journal of Asian Ceramic Societies, 2019
P. Nagaraju, Y. Vijayakumar, M. V. Ramana Reddy
Monoaromatics hydrocarbons such as benzene, toluene, ethylbenzene, and xylene (BTEX) are a group of hazardous pollutants which originate from sources such as gas and oil extraction fields and refineries and the paint, glue and petrochemicals industries. Among them, benzene-based compounds have been commonly using in the paint industry during the recent past. Hence, gaseous pollutants have been released into the atmosphere. Toluene is used in the rubber industry, printing inks, leather tanners, adhesives, and disinfectants. It is also used as an octane booster reagent in gasoline fuels for internal combustion engines and as solvents, paint thinners, and many chemical reactants. Ethylbenzene is widely used in the petrochemical industry as an intermediate compound for the production of styrene. It is used as a fuel and solvent and in the preparation of other chemicals. Xylene is a sweet-smelling, colorless aromatic hydrocarbon available in vapor or liquid form. It is extensively used in the rubber and petrochemical industries and refineries. Inhalation of these BTEX gases may lead to dizziness, nausea, vomiting, headache, carcinogenic and mutagenic problem, and effects on other severe health issues [20]. A mechanism for recognizing these gases as quickly and accurately as possible, notably in very low concentrations (ppm levels), is, therefore, essential. The various available methods for recognizing BTEX gases have many drawbacks, such as slow response, high equipment costs, and complications in analysis as well as energy consumption. Recently, many researchers have been working on gas sensors to overcome the above shortcomings. The sensors facilitate detection of these gases and feature very high sensitivity and selectivity with low cost and high portability. The present study examines the deposition of ZnO thin films by a spray pyrolysis technique at various precursor concentrations with optimized deposition parameters. Showing the influence of the precursor concentrations on their microstructures is systematically reported, and the films are also exposed to different concentrations (in ppm) of benzene, toluene, ethylbenzene, and xylene to measure their sensitivity and selectivity as sensors.