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This post was last edited by jordan569 on 2013-1-6 at 22:35. The hydrocracking process for medium- and high-temperature coal tar is an important innovation in the technology for comprehensive utilization of such resources. It not only provides new methods and approaches for the comprehensive utilization of medium- and high-temperature coal tar in China, but also brings significant economic benefits to its processing; moreover, it holds great importance for environmental protection. The medium- and high-temperature coal tar referred to in this patent is the coal tar produced during the gasification, coking, or production of semi-coke of coal. The aforementioned medium- and high-temperature kerosene, at a pressure of up to 20.0 MPA, passes through the refining and cracking reactors either in a single pass or with partial or full recycling of the residual oil; subsequent processes such as fractionation, refining, and dewaxing are then used to produce liquefied gas, naphtha, fuel oil, sulfur, and liquid ammonia. The key to this patent lies in utilizing hydrocracking process technology to achieve the ultimate goal of modifying medium- and high-temperature coal tar. The objective of this invention is to achieve rational comprehensive utilization of resources and environmental protection by applying modern technologies from the oil refining industry to the coal chemical sector in a modified manner, thereby producing high-quality products from medium- and high-temperature coal tar, enhancing the value of such coal tar, and protecting the environment. Since medium- and high-temperature coal tar originates from the coking and gasification dry distillation stages of coal, it is a product of thermal cracking. The properties of medium and high-temperature coal tar are very complex; their chemical composition consists mainly of aromatic compounds. It contains low levels of alkanes and alkenes, as well as small amounts of oxygen-containing, nitrogen-containing, and sulfur-containing compounds. Oxides are mainly various corresponding phenols with weak acidity ； Nitrogen-containing compounds are mainly pyridine, quinoline, and their derivatives, which have weak basicity ； Sulfur-containing compounds mainly include thiophenes, thiolues, thiophenols, thioethers, thiazoles, etc. These oils are rich in aromatic hydrocarbons, resins, and asphaltenes, while containing little in the form of large-molecule linear hydrocarbons. Under conditions of temperature, pressure, catalysts, and hydrogen presence, the sulfides, nitrides, and oxides present in medium- to high-temperature coal tar react with hydrogen to produce hydrogen sulfide, ammonia, and water. Resins and asphaltenes give rise to small-molecule hydrocarbons, whereas aromatic hydrocarbons and long-chain large-molecule hydrocarbons undergo saturation and cracking to produce naphthenes and short-chain small-molecule hydrocarbons, thereby achieving the goal of upgrading the material. . Note $ # , $ $