JP3497539B2 - Catalytic hydrocracking of resins - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a cracked product oil having good properties from resins (including waste resins) or a mixture of resins and heavy hydrocarbons (hereinafter referred to as resins). The present invention relates to a catalyst for obtaining the catalyst and a catalytic hydrocracking method using the catalyst.

[0002]

2. Description of the Related Art At present, the following methods have been proposed as cracking / oilification technologies for obtaining cracked oils from resins. (1) Pyrolysis method (2) Catalytic pyrolysis method (3) Catalytic hydrocracking method

[0003]

Each of the methods for obtaining a decomposition product oil from the above-mentioned resins has the following problems. Pyrolysis method of (1) High reaction temperature is required compared with catalytic pyrolysis method and catalytic hydrogenolysis method. In the temperature range where the decomposition of the resins proceeds sufficiently, problems such as the recombination of reaction intermediates and the formation of carbonaceous matter by polycondensation and the coloration of the oil produced by decomposition are caused.
The production of carbonaceous matter not only lowers the yield of cracked oil, but industrially causes clogging of the equipment and piping, which hinders smooth operation of the equipment. (2) Catalytic pyrolysis method In the catalytic pyrolysis method using a solid acid catalyst such as zeolite, the reaction temperature may be lower than that in the pyrolysis method, but the amount of carbonaceous substances is increased and the carbonaceous substance adheres to the surface of the catalyst, resulting in catalytic activity. It is necessary to remove carbonaceous matter in order to reduce The catalytic hydrogenolysis catalyst represented by Ni / SiO ₂ —Al ₂ O ₃ in (3) is a technology already established in the field of petroleum refining, but when resins are used as raw materials, Poisoning of the catalyst occurs due to the inclusion of various kinds of impurities such as pigments and plasticizers contained therein and metals such as V represented by heavy hydrocarbons such as V. The basic problem in applying a catalyst to the decomposition and oilification of resins is how to prevent the formation of carbonaceous matter on the solid acid catalyst. When using an acid catalyst, the temperature is lower than that of the thermal decomposition method.
Decomposition progresses with>, but precipitation of carbonaceous substances on the catalyst and coloring of the decomposition product oil due to polycondensation based on the acid function cannot be avoided. In general, solid acids have pores with an inner diameter of several Å to several hundred Å, and macromolecules such as resins cannot enter into these pores and the catalytic active sites cannot be effectively utilized. Therefore, most of the currently proposed decomposition and oilification of resins is a method of converting it into high-quality oil using a solid catalyst after lowering the molecular weight by a thermal decomposition method, which also complicates the equipment. , High energy efficiency cannot be obtained.

[0004]

According to the present invention, a carbon carrier is provided with dehydrogenating ability instead of a conventional solid acid catalyst, and hydrogen dehydrogenated from resins moves on the carrier to improve hydrogenating ability. Another object of the present invention is to provide a method for decomposing and oiling resins using a bifunctional catalyst having a dehydrogenation and hydrogenation ability, which utilizes the reverse spillover effect of hydrogenating a hydrocarbon on a metal. That is, the present invention belongs to the catalytic hydrocracking process of (3),
Using resins as a raw material, in a one-step reaction, little gaseous hydrocarbons are generated, and high-quality light / medium oil is converted into cracked product oil with high yield and high conversion rate, and cracked residue is catalyzed. It is intended to provide a method of using as fuel without being separated from. Such an object is that the ash content of the present invention is 3% by weight.
Pyrophores on the carbon carrier obtained by activating carbonized carbon obtained by dry distillation of brown coal of less than 400 to 800 ℃ in carbon dioxide atmosphere at 600 to 900 ℃ in carbon dioxide or steam atmosphere. A catalyst obtained by supporting one or more metals selected from Table VIII group, reducing the supported metal, and then subjecting to sulfurization treatment, and a resin or resins and heavy hydrocarbons It can be achieved by a method for catalytic hydrogenolysis of resins, which comprises heating the mixture in the presence of hydrogen.

The catalyst for catalytic hydrocracking of resins of the present invention and the method for catalytic hydrocracking of resins using the same are described in detail below. The most important point of producing a carbon support having a dehydrogenation ability and selecting a carbon support is the most important point of a bifunctional catalyst composed of a metal having a hydrogenation ability. As a raw material of a carbon support suitable for the purpose, elemental analysis value wt% (C; 60 to 80, O; 40 to 20)
And lignite having an average number of aromatic ring groups in the range of 0.5 to 1.5 is used. It is necessary that the ash content in the brown coal is less than 3% by weight, the smaller the ash content, the more desirable, and 1.5% by weight or less is particularly preferable. In the case of lignite with a high ash content, for example, Morwell coal, which generally contains 10% by weight of ash, cannot be used as a raw material of the present invention, but it is deashed to obtain an ash content of 3% by weight.
If it is less than the value, it can be used. Particularly preferred types of brown coal include Yallourn coal, demineralized Morwell coal and the like.

The method for producing the catalytic carbon carrier used in the present invention is as follows. Lignite in a CO ₂ stream at 400-800 ℃
The dry-distilled charcoal obtained by heating and dry distillation is further activated at 600 to 900 ° C. in a CO ₂ or steam atmosphere or in the coexistence of CO ₂ · steam to obtain a carbon carrier. The activation is particularly effective when treated in CO ₂ at 800 to 900 ° C. Next, the above carbon support is immersed for several hours in an aqueous solution of a metal salt selected from Group VIII of the Periodic Table, preferably 0.5 to 5 N, and the metal is supported by an impregnation method. Since the carbon carrier is activated, it quickly adsorbs most dissolved metal salts. In this case, the amount of metal supported is 0.1% by weight.
From 10% by weight is sufficient.

After the carbon support on which the metal is adsorbed is dried, the supported metal salt is thermally decomposed in an N ₂ atmosphere at 300 to 500 ° C., reduced and then sulfurized to be used. Alternatively, it is also possible to catalytically hydrocrack the resin with the carbon support carrying the metal salt in the presence of a sulfiding agent and hydrogen. When decomposing / oilifying sulfur-containing resins, this sulfurization treatment or addition of a sulfurizing agent is not necessary. When applying to sulfur-free resins, the above sulfurization treatment or sulfurizing agent is used. The same effect can be obtained by using it.

Examples of the Group VIII metal of the periodic table supported on a carbon carrier include iron, cobalt, nickel and the like. Iron is particularly preferable in terms of cost and easiness of handling, and its nitrate and acetic acid are preferable because of easiness of reduction. It is preferable to use salt or the like. For the reduction, H ₂ or CO, or a mixture of H ₂ and CO can be used. Preferably 400-500 under H ₂ atmosphere
Reduce at ℃ for several hours. The sulfurization treatment can be carried out by treating the reduced metal-supported carbon support in a gas containing H ₂ S or with a sulfur-containing inorganic or organic compound, for example, a sulfurizing agent such as mercaptan, disulfide or carbon disulfide. Alternatively, even if the carbon support carrying the metal salt is used as it is as a catalyst in the presence of hydrogen and a sulfiding agent such as mercaptan, disulfide or carbon disulfide, the same effect as the sulfidized catalyst can be obtained.

The catalyst thus obtained becomes a bifunctional catalyst having a hydrogen transfer phenomenon effect and exhibits the following characteristics. The catalytic hydrocracking accompanied by this hydrogen transfer phenomenon is based on thermal decomposition and hydrocracking and hydrogen transfer from a coke precursor to a light fraction by a catalyst. The hydrogen transfer phenomenon is also called the reverse spillover phenomenon and is a theory that explains the catalytic phenomenon.The hydrogen of asphaltene or pre-asphaltene adsorbed on activated carbon is desorbed, and the hydrogen moves on the activated carbon, and the hydrogen on the activated carbon The catalytic hydrogenolysis reaction of heavy hydrocarbons can be explained by transferring the hydrogen to a raw material hydrocarbon on a metal having a chemical conversion ability.
In the catalytic hydrocracking reaction between the catalyst and the resins, when the resin to be decomposed and oiled is thermoplastic polyethylene, polypropylene, polystyrene, etc., the catalyst is melted in the reaction temperature range shown below, and the catalyst and H ₂ are sufficiently contacted with each other. react. It is also possible to mix the resin and heavy hydrocarbons (ultra-heavy oil, oil sand bitumen, etc.) and perform decomposition and oilification.

The decomposition / oilification reaction of resins according to the present invention is
For example, as in the examples described below, it is performed in a batch system,
The catalyst can be molded and filled in a fixed bed type / moving bed type reactor for reaction, or can be applied to a fluidized bed type reactor. The reaction conditions for the decomposition and oilification of resins are: general-purpose thermoplastic resins such as polyethylene, polypropylene, polystyrene, etc., when a catalyst supporting iron is used, the reaction temperature is 340 to 490 ℃, and the hydrogen pressure is 10 to 80 kg. / Cm ² , catalyst / resins (weight ratio) = 1/100 to 1/10, reaction time (min) 10
To 100, particularly preferably a reaction temperature of 360 to 450 ° C,
Hydrogen pressure 20-70kg / cm ² , catalyst / resins (weight ratio) = 2
/ 100 to 8/100, reaction time (min) 15 to 70.

[0011]

[Composition of raw material lignite]

Weight% C: 67.2, H: 4.3, N: 1.0, S: 0.2,
O: 27.2, ash content: 0.6 The properties of the obtained catalyst were as follows. Iron loading 5% by weight / Carbon carrier specific surface area 840 m ² / g Pore volume 0.18 cm ³ / g MCH conversion 70.7% Particle size 20-60 mesh [decomposition / oilification method] Reaction with shaking autoclave with internal volume of 50 ml Used as a container. After 10 g of polypropylene, 0.3 g of the catalyst obtained as described above (catalyst addition amount: 3% by weight) and 0.015 g of carbon disulfide were charged into a reaction vessel, hydrogen pressure was 30 kg / cm ² and the results are shown in Table 1. The reaction was performed at a predetermined reaction temperature and reaction time. The obtained gaseous hydrocarbon was analyzed by gas chromatography and the liquid product was analyzed by distillation gas chromatography. Further, the insoluble matter of n-hexane was used as a solid. The results are shown in Table 1.

[0012]

[Table 1]

Examples 3 to 4 and Comparative Examples 5 to 6 The decomposition and oilification reactions were carried out in the same manner except that polyethylene was used as the resin. The results are shown in Table 2.

[0014]

[Table 2]

[0015]

INDUSTRIAL APPLICABILITY The present invention utilizes a catalyst in which a metal of Group VIII having a hydrogenating ability is carried on a carbon carrier having a dehydrogenating ability, which is prepared from brown coal having a low ash content as a raw material, and is used for contacting resins. Since hydrocracking is performed, it has the following excellent effects. (1) The conversion rate of the raw material is high, the yield of oil is high, and high-quality oil is obtained. (2) It is possible to use one-stage oil instead of the conventional two-stage oil type. (3) The used catalyst can be used as a fuel without separating the reaction residue.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-60-58239 (JP, A) JP-A-48-52866 (JP, A) Takashi Asano, 3 others, Coal and Petroleum Separate Co-Processing, Japan Petroleum Institute Annual Meeting Abstracts, 1992, 35, 60-61 (58) Fields investigated (Int.Cl. ⁷ , DB name) B01J 21/00-38/74

Claims (2)

(57) [Claims] 1. A dry-distilled coal obtained by carbonizing brown coal having an ash content of less than 3% by weight in a carbon dioxide gas atmosphere at 400 to 800 ° C. is activated at 600 to 900 ° C. in a carbon dioxide gas or steam atmosphere. Catalytic hydrogen of resins obtained by supporting one or more metals selected from Group VIII of the Periodic Table on the carbon carrier obtained by the above, reducing the supported metals, and then subjecting to sulfurization treatment. Chemical decomposition catalyst and resin or resins and heavy hydrocarbons
Characterized by heating the mixture with and in the presence of hydrogen.
Method for catalytic hydrogenolysis of resins. 2. Lignite having an ash content of less than 3% by weight is added to a carbon dioxide gas atmosphere.
Dry-distilled charcoal obtained by carbonization at 400-800 ℃
Activated at 600-900 ℃ in acid gas or steam atmosphere
The carbon carrier thus obtained was selected from Group VIII of the Periodic Table.
After supporting one or more metals, the supported metal
A catalyst for catalytic hydrocracking of resins obtained by reducing
Sulfide resins or mixtures of resins and heavy hydrocarbons
Of resins that are heated in the presence of an agent and hydrogen
Catalytic hydrocracking method.