Catalytic reforming aromatic hydrocarbons production

Cyclic Hydrocarbons. The cyclic hydrocarbon intermediates are derived principally from petroleum and natural gas, though small amounts are derived from coal. Most cycHc intermediates are used in the manufacture of more advanced synthetic organic chemicals and finished products such as dyes, medicinal chemicals, elastomers, pesticides, and plastics and resins. Table 6 details the production and sales of cycHc intermediates in 1991. Benzene (qv) is the largest volume aromatic compound used in the chemical industry. It is extracted from catalytic reformates in refineries, and is produced by the dealkylation of toluene (qv) (see also BTX Processing). 

Liquid solvents are used to extract either desirable or undesirable compounds from a liquid mixture. Solvent extraction processes use a liquid solvent that has a high solvolytic power for certain compounds in the feed mixture. For example, ethylene glycol has a greater affinity for aromatic hydrocarbons and extracts them preferentially from a reformate mixture (a liquid paraffinic and aromatic product from catalytic reforming). The raffinate, which is mainly paraffins, is freed from traces of ethylene glycol by distillation. Other solvents that could be used for this purpose are liquid sulfur dioxide and sulfolane (tetramethylene sulfone). 

In Europe naphtha is the preferred feedstock for the production of synthesis gas, which is used to synthesize methanol and ammonia (Chapter 4). Another important role for naphtha is its use as a feedstock for steam cracking units for light olefins production (Chapter 3). Heavy naphtha, on the other hand, is a major feedstock for catalytic reforming. The product reformate containing a high percentage of Ce-Cg aromatic hydrocarbons is used to make gasoline. Reformates are also extracted to separate the aromatics as intermediates for petrochemicals. 

Naphta catalytic reforming (CR) is one of the basic processes in the petroleum industry. Catalytic reforming is an important process for the production of aromatic hydrocarbons, as well as being employed to enhance octane number (RONC) in gasolines and an important hydrogen producer [1]. 

Petroleum refining for the production of fuels and lubricants remains the dog that wags the taiP when chemicals from petroleum are considered. This does not mean that the dog never circles after his tail witness the success of catalytic reforming processes, greatly stimulated by the need for aromatic hydrocarbons as chemicals. But it does mean that when petroleum or its frac-... 

Eight carbon aromatics (xylenes and ethylbenzene) represent another very important chemical intermediate derived from catalytic reforming (43,99). These products can be formed by a similar combination of reactions—directly from octanes or from higher hydrocarbons by the loss of alkyl groups. The isomer distribution is the result of secondary reactions which are influenced strongly by operating conditions. 

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