JPH0437841B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing hydrogenated petroleum resins. More specifically, the present invention relates to a novel method for producing hydrogenated petroleum resin that can significantly maintain catalytic activity, which is characterized by removing the sulfur content contained in the petroleum resin as a first step, and then performing hydrogenation. [Prior art] Petroleum resins obtained by polymerizing thermal decomposition products of petroleum naphtha in the presence of a Friedel-Crafts catalyst or by thermally polymerizing them are mainly used as adhesives or adhesives such as tackifier fire and plastic compounds. Resins suitable for these uses usually have a softening point of 60 to 140°C and a molecular weight of about 600 to 10,000. In particular, these hydrogenated petroleum resins have good weather resistance, color tone, stability, and compatibility with rubber, polyolefin, ethylene-vinyl acetate copolymer, etc., so they are suitable as resins for use in the above applications. Especially excellent. However, since the petroleum resin used for hydrogenation contains 100 to 500 ppm of sulfur, a large amount of catalyst is required, and the hydrogenation reaction is difficult to proceed unless under severe conditions of high temperature, high pressure, and long time. Conventionally, powdered or molded nickel catalysts, or platinum metal catalysts such as platinum, rhodium, and palladium are known as catalysts used in the hydrogenation reaction of petroleum resins. As the hydrogenation method, a batch suspended bed system, a flow suspension bubble column, or a flow fixed bed system is employed. When hydrogenating by this conventional method, in a suspended bed, a large amount of powdered catalyst is required because the catalyst is deactivated by sulfur, and it is difficult to filter a high viscosity liquid to remove the catalyst. On the other hand, in a fixed bed, sulfur adheres to the packed catalyst and the activity decreases in a short period of time, resulting in a short catalyst life and being economically impractical. In particular, it is very difficult to use expensive precious metals in fixed beds, considering the possibility of poisoning. Also, methods for removing sulfur in the form of hydrogen sulfide from petroleum resins are known, but when hydrogen gas is recycled, the generated hydrogen sulfide is adsorbed on zinc oxide, or the gas is washed with an alkaline aqueous solution. It is complicated and requires processes such as [Problems to be Solved by the Invention] The present inventors have conducted intensive research regarding the problem of the prior art, which is the reduction in the hydrogenation ability of the catalyst due to sulfur poisoning. When a small amount of the reduced powder catalyst and a petroleum resin containing a large amount of sulfur were stirred under hydrogen pressure, it was surprisingly discovered that the petroleum resin contained only a trace amount of sulfur.Based on this knowledge, the present invention was completed. I came to the conclusion. That is, in hydrogenating petroleum resins having aromatic nuclei and/or double bonds, the present invention involves placing petroleum resins and hydrogen gas in parallel in a reactor filled with a shaped catalyst whose hydrogenation capacity has been reduced due to sulfur poisoning. Sulfur is removed from the petroleum resin by heating it in a stream, and aromatic nuclei are produced by heating the desulfurized petroleum resin in a cocurrent flow with hydrogen gas into a reactor filled with a catalyst capable of hydrogenation. It is an object of the present invention to provide a novel method for producing hydrogenated petroleum resin, which is characterized by hydrogenating double bonds and/or by maintaining the life of a hydrogenation catalyst at an economically advantageous level. . [Means for solving the problem] The petroleum resin having an aromatic nucleus and/or double bond according to the present invention is an aromatic hydrocarbon having a double bond in a side chain or having a double bond in a condensed ring. Refers to a homopolymer of aromatic hydrocarbons or olefins, or a polymer of a mixture of two or more of the aromatic hydrocarbons and olefins, in the presence of a Friedel-Crafts catalyst such as aluminum chloride or boron trifluoride. It can be obtained by polymerization or thermal polymerization. Examples of aromatic hydrocarbons include styrene,
Examples include α-methylstyrene, vinyltoluene, vinylxylene, propenylbenzene, indene, methylindene, and ethylindene.
Examples of olefins include butene, pentene, hexene, heptene, octene, butadiene, pentadiene, cyclopentadiene, dicyclopentadiene, octadiene, and the like. In the present invention, the catalyst used for removing sulfur may be any catalyst that is poisoned by sulfur and has a reduced hydrogenation ability but retains desulfurization ability.
Examples include supported molded catalysts of nickel or platinum metal elements such as platinum, palladium, ruthenium, and rhodium, and catalysts containing dissimilar metals such as copper, zinc, manganese, chromium, and barium.
The poisoned catalyst may be a shaped catalyst used in the hydrogenation of petroleum resin from which sulfur has been removed in the present invention, which has been used for a long reaction and has a reduced hydrogenation activity, or it may be one from another process. . The amount of sulfur attached to the poisoned catalyst is preferably 15% or less based on the weight of the catalyst. If it exceeds 15%, the sulfur removal ability rapidly decreases, which is not preferable. As the catalyst used for hydrogenation of the petroleum resin from which sulfur has been removed, a hydrogenation catalyst is applied, such as a supported molded catalyst of nickel or a platinum metal element such as platinum, palladium, ruthenium, rhodium, etc. Catalysts containing different metals such as manganese, chromium, and barium can be proposed. This catalyst may be a commercially available shaped catalyst or a separately prepared shaped catalyst. The shape of the catalyst used may be cylindrical, extrudate, pellet, or spherical. In the present invention, the petroleum resin may be melted and charged as it is to the packed bed of the fixed bed catalyst, or it may be diluted with a suitable solvent such as cyclohexane and then charged. The reaction method includes a catalyst packed bed for sulfur removal,
A so-called gas-liquid upward parallel flow method may be used, in which petroleum resin is introduced from below into a catalyst packed bed for hydrogenation reaction, and hydrogen gas is made into fine bubbles and hydrogenated efficiently on the catalyst surface. A so-called trickle-bed method may be adopted, in which the liquid phase is allowed to drip from above to below, forming a thin film of petroleum resin to efficiently perform hydrogenation in the descending liquid phase. Further, the methods may be different for both the sulfur removal reaction and the hydrogenation reaction. Either the hydrogen gas is passed through the catalyst layer that removes sulfur and the catalyst layer that performs the hydrogenation reaction, or
It may be circulated, or the gas and liquid may flow in the same flow. The conditions for sulfur removal are as reaction pressure 30~
300Kg/cm ² , preferably 50 to 250Kg/cm ² . The hydrogen supply amount is 2 to 50% of the theoretical hydrogen absorption amount of petroleum resin.
The reaction temperature is preferably 200 to 350°C. The amount of petroleum resin supplied is the WHSV for the catalyst in the sulfur removal reaction layer.
(Weight Hourly Space Velocity; refers to the weight of petroleum resin supplied per hour relative to the weight of catalyst packed) is preferably set to 0.01 to 10. The hydrogenation conditions for the petroleum resin from which sulfur has been removed according to the present invention are such that the reaction pressure is 30 to 300 Kg/cm ² , preferably 50 to 250 Kg/cm ² . The amount of hydrogen supplied is 2 to 50 times the theoretical hydrogen absorption amount of petroleum resin, preferably 2 to 50 times.
It is 30 times more. The reaction temperature is 200-350°C, preferably 230-320°C. The supply amount of petroleum resin from which sulfur has been removed is determined by the WHSV for the hydrogenation reaction layer.
It is preferably 0.01 to 10. The reaction conditions for each layer depend on the desired sulfur removal efficiency,
It is determined as appropriate, taking into consideration the hydrogenation rate, reactor specifications, etc. [Example] The present invention will be explained in detail with reference to Examples below. Example 1 Two reactors having a length of 2 m, an inner diameter of 21 mm, and an internal volume of 0.7 were used, one of which was used as a sulfur removal reactor and the other as a hydrogenation reactor. The outside of each reactor was heated with a heater, and in order to keep the internal temperature constant, it was divided into five blocks so that the temperature could be adjusted. In the sulfur removal reactor, a molded nickel catalyst (manufactured by JGC Chemical Co., Ltd.) was used, which had 0.3% sulfur by weight attached to the catalyst and had a reduced hydrogenation capacity.
The hydrogenation reactor was filled with 600g of N111 poisoned catalyst, and the hydrogenation reactor was filled with new molded nickel catalyst N111.
(manufactured by JGC Chemical Co., Ltd.) was filled with 600 g. Temperature inside each reactor: 245-255℃, pressure: 200Kg/cm ²
Hydrogen gas 2Nm ² /h and petroleum resin ("Petrosin #120", softening point 120℃, sulfur content 100~
150ppm, aromatic content 54%, manufactured by Mitsui Petrochemicals)
was fed from the lower part of the sulfur removal reactor at a feed rate of 300 g/h, and the gas and liquid coming out from the upper part of the reactor were flowed as they were from the lower part of the hydrogenation reactor to perform hydrogenation. Next, after separating gas and liquid in a separator, the hydrogenated petroleum resin was taken out of the reaction system. Next, continuous operation was performed to confirm the deflow activity of the sulfur removal catalyst, the hydrogenation activity and life of the hydrogenation catalyst, and the hydrogenated resin obtained after each time period was analyzed. The results are shown in the table. Incidentally, the sulfur analysis in the petroleum resin was conducted according to JIS K-2264. Further, the hydrogenation rate was determined by the following measuring method. That is, 274.5nm by an ultraviolet spectrometer
The absorbance at was measured, and the hydrogenation rate was calculated using the following formula. (A-B) x 100/A (%) (In the formula, A indicates the absorbance of the raw petroleum resin, and B indicates the absorbance of the hydrogenated petroleum resin.) Example 2 The reactor in Example 1 was used to remove sulfur. The reactor was equipped with a molded nickel catalyst (ST-111 manufactured by Sakai Chemical Industry Co., Ltd.) with 0.6% sulfur attached by weight to the catalyst.
The hydrogenation reactor was filled with 600g of unused and unpoisoned ST.
600 g of -111 catalyst was charged. Inside the sulfur removal reactor
Heat the inside of the hydrogenation reactor to 265-270℃, 230-235℃, maintain the pressure at 200Kg/ ^cm2 , and add 3N of hydrogen gas.
m ³ /h and petroleum resin (Petrozin #120) at a feed rate of 300 g/h were charged from the top of the sulfur removal reactor, and the gas and liquid coming out from the bottom was directly charged from the top of the hydrogenation reactor. , hydrogenation was performed. Thereafter, the same procedure as in Example 1 was carried out. The analysis results of the hydrogenated resin obtained for each time period are shown in the table. Comparative Example 1 For comparison, a reaction was carried out in the same manner as in Example 1 except that a desulfurization reactor was not used.
The analysis results of the hydrogenated petroleum resin obtained after each time period are also shown in the table. [Effects of the Invention] As is clear from the table, the activity of the hydrogenation catalyst according to the method of the present invention continues for a long period of time, and the effect is remarkable. 【table】

Claims (1)

[Claims] 1. When continuously hydrogenating petroleum resins containing aromatic and/or double bonds in a fixed bed, a catalyst whose hydrogenation ability has decreased due to poisoning with sulfur of 15% by weight or less based on the catalyst weight. Using,
By heating under hydrogen pressure, the sulfur content contained in the petroleum resin is removed in advance, and then,
A method for producing a hydrogenated petroleum resin, characterized in that hydrogenation is carried out using a catalyst having hydrogenation ability.