BTX aromatics

BTX (benzene-toluene-xylene) mixtures are an important petroleum refinery stream that is separated by extractive distillation (Fig. 1) from a hydrocarbon stream, usually a reformate, and followed by downstream fractionation for isolation of the pure materials for further treatment and use (Fig. 2). 

The BTX stream provides the individual components of the mixture for further use (Fig. 3). 

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The sulfolane process is a versatile extractant for producing high purity BTX aromatics (benzene, toluene, and xylenes). It also extracts aromatics from kerosines to produce low-aromatic jet fuels. 

As feedstocks progress from ethane to heavier fractions with lower H/C ratios, the yield of ethylene decreases, and the feed per pound ethylene product ratio increases markedly. Table 3-15 shows yields from steam cracking of different feedstocks, and how the liquid by-products and BTX aromatics increase dramatically with heavier feeds. 

Another glance at Table XI reveals that gas make is reduced when severity is dropped while BTX aromatics produced remains about the same over the severities studied. Since the amount of Co/400°F produced increases at lower severities, the percent BTX in the C5/400°F fraction decreases in order to retain a relatively constant aromatics production. 

Figure 7 shows the effect on ethylene production cost from naphtha cracking with BTX aromatics value increases as a parameter. (The basis we have used for determining the effect of aromatics price increases is given in Table XII). Figure 7 indicates that a 5 /gal increase in BTX... 

The thermal and catalytic conversion of different hydrocarbon fractions, often with hydrotreating and other reaction steps, is characterized by a broad variety of feeds and products (Table 1, entry 4). New processes starting from natural gas are currently under development these are mainly based on the conversion of methane into synthesis gas, further into methanol, and finally into higher hydrocarbons. These processes are mainly employed in the petrochemical industry and will not be described in detail here. Several new processes are under development and the formation of BTX aromatics from C3/C4 hydrocarbons employing modified zeolite catalysts is a promising example [10],... 

Dehydrocyclodimerization of liquefied petrol gas (propane and butane) can be performed to yield BTX-aromatics (Table2, entry 21). Modified ZSM-5 based catalysts are used, for example in the UOP cyclar process [33], and the process will become attractive for extraction of aromatics from natural gas fields containing further C3-C4 fractions. 

Process Economics Program Report SRI International. Menlo Park, CA, Isocyanates IE, Propylene Oxide 2E, Vinyl Chloride 5D, Terephthalic Acid and Dimethyl Terephthalate 9E, Phenol 22C, Xylene Separation 25C, BTX, Aromatics 30A, o-Xylene 34 A, m-Xylene 25 A, p-Xylene 93-3-4, Ethylbenzene/Styrene 33C, Phthalic Anhydride 34B, Glycerine and Intermediates 58, Aniline and Derivatives 76C, Bisphenol A and Phosgene 81, C1 Chlorinated Hydrocarbons 126, Chlorinated Solvent 48, Chlorofluorocarbon Alternatives 201, Reforming for BTX 129, Aromatics Processes 182 A, Propylene Oxide Derivatives 198, Acetaldehyde 24 A2, 91-1-3, Acetic Acid 37 B, Acetylene 16A, Adipic Acid 3 B, Ammonia 44 A, Caprolactam 7 C, Carbon Disulfide 171 A, Cumene 92-3-4, 22 B, 219, MDA 1 D, Ethanol 53 A, 85-2-4, Ethylene Dichloride/Vinyl Chloride 5 C, Formaldehyde 23 A, Hexamethylenediamine (HMDA) 31 B, Hydrogen Cyanide 76-3-4, Maleic Anhydride 46 C, Methane (Natural Gas) 191, Synthesis Gas 146, 148, 191 A, Methanol 148, 43 B, 93-2-2, Methyl Methacrylate 11 D, Nylon 6-41 B, Nylon 6,6-54 B, Ethylene/Propylene 29 A, Urea 56 A, Vinyl Acetate 15 A. 

BTX aromatics (4) Maleic anhydride Upgrading steam cracker C3 cuts... 

Alpha olefins, linear BTX aromatics Butene-1 Cyclohexane... 

UOP/BP BTX aromatics LPG New technology yields petrochemical grade BTX in one-step process. 1 1995... 

Thus, in refining, they employ reformers operating at hi severity but wth greater operating stability and improved gasoline yields, and in petrochemicals, the optimization of the production of BTX aromatics by the use of high-temperature reactors. 

Asidn, G. F Persak, R. A.. BTX aromatics eztractioo , UOP Process Division Teehn4Aogy Conference, Des Plainer Blmois (SepL/Nov. 1975). 

Naphtha is likely to remain the main feedstock for petrochemical operations because of the abihty of the feedstock to not only dehver both ethylene and propylene, but also BTX aromatics from the rapidly growing fires and speciality polymers markets (nylons, polyester etc.). 

With the exception of experiments at [29] 605°C, the gas fraction is the main product (58-71%), having a maximum yield at a temperature of about 700°C. BTX-aromatics increase from 1.6% at 605°C up to 16% at 805°C. Distillation residue is higher at lower temperature (at which heavier hydrocarbons are produced) and at the highest (since more condensed aromatics are present). Chlorine is present in the water and in the solids... 

For extractive distillation, extraction and absorption processes, highly selective solvents are required. The economic importance of extraction and extractive distillation processes can be recognized from the fact that the worldwide production of the BTX aromatics (benzene, toluene, xylenes, ethylbenzene) as important primary petrochemical products for the industrial manufacturing of many chemical products... 

BTX - Aromatics Hydrocarbon resins Industrial oils Pyrolysis pitch... 

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