JPH05434B2 - - Google Patents

Description

[Detailed description of the invention]

B. Object of the Invention Industrial Application Field The present invention relates to a method for low polymerizing a raw material containing _C4 to _C10 olefins and converting it into a high value-added middle distillate. Conventional technology As a conventional technology regarding the low polymerization of olefin,
There is UOP's Catalytic Condensation Process, which produces polymerized gasoline by polymerizing _C3 and _C4 olefins using solid phosphoric acid as a catalyst.
This process has no experience with _C6 or higher olefins or mixed olefins, and cannot handle the wide range of _C4 to _C10 olefin fractions. Similarly, C ₃ and C ₄ olefins are low-polymerized using ZSM-5 type zeolite to produce gasoline, kerosene,
Mobil's MOGD process for producing light oil may be applicable to a wide range of mixed olefins, but there are economical problems because the catalyst used is expensive zeolite. Furthermore, with conventional silica-alumina catalysts, which are the basis of solid acid catalysts, when reacting with such a wide range of mixed olefins, a large amount of heavy components are produced and coke accumulates on the catalyst. The regeneration cycle was short, making industrialization difficult. Problems to be Solved by the Invention The present invention provides a method for underpolymerizing raw materials containing olefins in the range of _C4 to _C10 and converting them into high value-added fractions such as gasoline, kerosene, and light oil. The purpose is to provide. (b) Means for solving the structural problems of the invention The method for producing a low polymer of olefin according to the present invention is to use a raw material containing an olefin in the range of C ₄ to _{C 10} with an alumina content of 10 to 50 Wt% and a surface area of
^50-600m2 /g, amorphous silica alumina with an average pore diameter of 10-100Å, 150-400℃, 30-100Kg/ ^cm2G
It is characterized by having a low polymerization step of contacting under reaction conditions. Note that the surface area is a value determined by PET surface area measurement method, and the average pore diameter is a value determined by mercury intrusion method and nitrogen adsorption method. The reaction conditions are 150-400℃, 30-100Kg/
The range of cm ² G is preferable, and by appropriately selecting reaction conditions within this range, gasoline in the low polymer,
The ratio of each fraction of kerosene and gas oil can be adjusted, and the yield of the desired fraction can be increased. The raw material for the reaction may be any raw material containing one or more olefins in the range of _C4 to _C10 . For the purpose of controlling the heat of reaction, it may be used as a raw material after being diluted with paraffin-based hydrocarbons. Alternatively, a mixture of C ₄ to _{C 10} mixed olefin and paraffin, such as catalytic cracking naphtha or pyrolytic naphtha, may be used as the raw material. By fractionating the low polymer obtained in this low polymerization step, a gasoline fraction, a kerosene fraction, and a gas oil fraction are obtained. In order to improve the yield of oligomers, it is desirable to recycle the unreacted olefin obtained during fractional distillation to the oligomerization step. Further, when paraffin is contained in the low polymerization product, the reaction heat may be suppressed by recycling the paraffin content to the low polymerization step. Each fraction obtained by fractional distillation is then hydrogenated to obtain a preferred product. Since the resulting gasoline fraction undergoes skeletal isomerization of olefins, the octane number necessary for the gasoline fraction is slightly improved. Regarding kerosene fractions, even if the raw material contains about 5% aromatics, on this catalyst, the alkylation reaction of olefins to aromatics is suppressed to the same extent as on a zeolite catalyst. It does not lower the smoke point required by product specifications. Such favorable results are obtained by using as a catalyst an amorphous silica alumina having a uniform average pore diameter of 10 to 100 Å, preferably 10 to 50 Å, similar to zeolite. On the other hand, the acid site that becomes the active site for the reaction can be controlled by controlling the aluminum content. The present invention will be specifically explained below using Examples. Examples 1 to 3 Into a reactor filled with 40 ml of amorphous silica alumina with an alumina content of 28 wt%, a surface area of 444 m ² /g, and an average pore diameter of 40 Å, a C ₄ -C ₁₀ mixed olefin distillate having the properties shown in Table 1 was charged. 40 minutes under the reaction conditions shown in Table 2.
A contact reaction was carried out by feeding at a flow rate of ml/hr. Product yields are shown in Table 2.

【table】

[Table] In this way, by selecting the reaction conditions, the production ratio of gasoline, kerosene (kerosene), gas oil (light oil), and heavy oil can be changed. Next, an example will be shown in which each fraction obtained by low polymerization under the conditions of Example 1 was hydrogenated. Using a Co-Mo catalyst, which is a common hydrogenation catalyst, each fraction was hydrogenated under the conditions of a reaction pressure of 50 Kg/cm ² G, LHSV = 1 hr ^-1 , and a hydrogen supply amount of 300 N/oil (low polymer). The reaction was carried out. However, the reaction temperature is 250℃ for gasoline fraction, 275℃ for kerosene fraction, and 275℃ for gas oil fraction.
The test was carried out at 300°C, and at 350°C for heavy oil fractions. Table 3 shows the physical properties of each fraction.

[Table] By hydrogenating each fraction, each fraction can be stabilized and its quality can be improved. In particular, kerosene and gas oil fractions pass the standards as products, and it can be seen that they can be made into desirable products by hydrogenation. Example 4 Average pore diameters of 20 Å, 40 Å and 150 Å shown in Table 4
Using amorphous silica alumina as a catalyst, the same raw material as in Example 1 was heated at 260℃, 50Kg/cm ² G, LHSV.
Figure 1 shows the relationship between the average pore diameter and the catalyst activity and life when the reaction was carried out at = 1 hr ^-1 . In Figure 1, the horizontal axis represents elapsed time, and the vertical axis represents catalytic activity (olefin conversion rate), where ○ indicates an average pore diameter of 20 Å, ● indicates an average pore diameter of 40 Å, and △ indicates amorphous with an average pore diameter of 150 Å. This data corresponds to silica alumina.

[Table] The smaller the average pore diameter, the higher the catalytic activity;
It can be seen that it is preferable to set the thickness to 100 Å. When the average pore diameter exceeds 100 Å, the lifetime becomes long but the activity is low. C. Effects of the Invention _C4 to _C10 olefins can be low-polymerized and converted into high value-added fractions such as gasoline, kerosene, and light oil.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the relationship between the average pore diameter, catalyst activity, and life of a catalyst when amorphous silica alumina is used as a catalyst.

Claims (1)

[Claims] 1. A raw material containing olefin in the range of C ₄ to _{C 10} , with an alumina content of 10 to 50 Wt% and a surface area of 50 to 50%.
600m ² /g, an average pore diameter of 10 to 100 Å, is brought into contact with amorphous silica alumina under reaction conditions of 150 to 400°C and 30 to 100 kg/cm ² G. Method for producing polymers. 2. A method for reducing olefins consisting of three steps: the step of lower polymerization described in claim 1, the step of fractionating the effluent from the lower polymerization step, and the step of hydrogenating the fractionated low polymer fraction. Method for producing polymers.