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Methods for producing needle coke: 1. Method without physical perturbation: 1.1. Preparation using a single type of raw material – (1) Direct purification method (the method currently used in industry); (2) Modification method (difficult to implement in industry); (3) Preparation method using special raw materials (difficult to implement in industry). 1.2. Co-carbonization method: (1) Traditional co-carbonization method; (2) Polymer method (difficult to implement in industry); (3) Nucleating agent method (difficult to implement in industry); (4) Separation and distribution method – first separating the components of the raw materials through extraction, and then studying carbonization or co-carbonization of different component groups to explore the optimal raw material composition for producing needle coke. Commonly used reagents include benzene, toluene, n-heptane, etc. Mochida et al. used benzene to fractionate pitch into benzene-soluble and benzene-insoluble components, which were then co-carbonized. The study found that the ratio between these two components has a significant impact on the products; a higher proportion of benzene-soluble components facilitates the formation of needle coke. However, excessively low levels of benzene-soluble components lead to a decrease in yield. Li et al. used toluene and heptane to divide alkylated petroleum asphalt into three fractions: heptane-soluble substances, heptane-insoluble–toluene-soluble substances, and toluene-insoluble substances. Now, the carbonized products of the three types of components are compared with those of naphthenic petroleum pitch. Calculations reveal that the sum of the mesophase contents in the carbonized products of the three components is not equal to the mesophase content in the carbonized product of naphthenic petroleum pitch, which proves that there are interactions between the components. Subsequently, pairwise co-carbonization studies of the components were conducted. It was found that, except for a relatively weak interaction between the insolubles in n-heptane and toluene, the co-carbonized products of the other two types of components exhibit strong interactions, thereby promoting the formation of high-quality mesophase. At the same time, by analyzing the various component groups, it was determined that cycloalkyl groups have a greater impact on the coking process than linear alkanes. 2. Physical perturbation assistance methods: mechanical stirring, electromagnetic fields, etc.