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Are you still distinguishing naphtha by "heavy or heavy"? 2016-10-20 Wang Xiaolong Petrochemical Network Energy [Introduction] The editor often hears questions from customers, "If you want to buy naphtha, how much does it cost in the current market?" Whenever I hear such a question, I always feel a headache. The editor always answers like this, you need to know what index of naphtha you need, or the purpose of buying naphtha. As we all know, naphtha is a mixture with complex and diverse components. After getting a naphtha product index and a series of numbers, you may still have doubts, does this meet the downstream requirements? What kind of naphtha should be chosen? Wang Xiao, editor of Longzhong Naphtha, will explain the composition of straight-run naphtha in naphtha and some downstream uses in this article. Straight-run naphtha, as a by-product of atmospheric and vacuum units, is mainly composed of normal alkanes, isoparaffins, naphthenes and aromatic hydrocarbons. According to its downstream uses, catalytic reforming raw materials, cracked ethylene raw materials and gasoline blending components are still its three main uses. The hydrocarbon composition requirements of naphtha vary greatly for different uses. Generally, n-alkanes are ideal raw materials for cracking to produce ethylene. The steam cracking process using naphtha as raw material is the main technical means for producing ethylene. The properties of the raw materials have a decisive impact on the cracking results. , its cracking performance and product yield are determined by the different contents of n-alkanes, isoparaffins, cycloalkanes and aromatic hydrocarbons in the raw materials, as well as the different carbon molecular weights. Therefore, when purchasing naphtha raw materials for cracking units, naphtha with high n-alkanes should be selected as much as possible. The yields of ethylene, propylene and butadiene of n-alkanes are generally higher. Naphthenes and aromatic hydrocarbons are ideal feedstocks for reforming. When the catalytic reforming process produces aromatics, the hydrocarbon composition and distillation range of the raw material have a great impact on the liquid recovery and aromatic yield of the reforming unit. Generally, the potential content of aromatic hydrocarbons or aromatic hydrocarbon index is used to indicate the quality of reforming raw materials. That is, the higher the content of alkanes and aromatic hydrocarbons in the raw material, the greater the aromatic hydrocarbon yield and the higher the octane number of the reformed oil. Some isoparaffins have high anti-knock index due to their high anti-explosion index. For more information on local refining and loading prices of crude oil, please follow the WeChat public account Longzhong Group.: longzhongjituan1988 and lower density, it is an ideal clean gasoline blending component for gasoline blending components. Some isoparaffins in naphtha have higher octane numbers and have the advantage of not containing olefins and aromatics, making them ideal clean gasoline blending components. Traditionally, naphtha is generally cut into light and heavy components. Light naphtha is used as ethylene raw material or gasoline blending component, while heavy naphtha is used as reforming raw material. However, traditional cutting and raw material selection requirements fail to fully realize the optimal utilization of naphtha in terms of hydrocarbon composition. On the one hand, the ethylene raw material (light naphtha C3~C6) contains some naphthenes and aromatic hydrocarbons, which affects the triene mass yield and is prone to coking. ； On the other hand, the reforming raw material (heavy naphtha C7~C11) contains some n-alkanes, which affects the operation of the reforming unit and the liquid quality yield. Longzhong Petrochemical Network recommends that in the process of purchasing naphtha raw materials, you should not simply classify it by "heavy", but also pay attention to the components of naphtha, so that you can efficiently utilize limited naphtha resources and obtain maximum profits.