JP4071929B2 - Method and apparatus for recovering catalyst components from spent catalyst - Google Patents

Description

上表のように、実施例１および２は比較例１に比し回収した触媒粉末中の無機繊維織布の割合が大幅に低減できていることが確認された。
【００２１】
【発明の効果】
本発明によって無機繊維を含む廃触媒から触媒成分原料を効率よく回収できるとともに、従来廃棄されていた触媒を再利用できるので現在大きな問題となっている産業廃棄物削減に効果がある。
【図面の簡単な説明】
【図１】実施例で用いた廃触媒を小片にする装置の概略図。
【図２】実施例で用いた廃触媒小片を破砕するミキサの概略図。
【図３】比較例で用いた回転刃を用いた廃触媒小片を破砕するミキサの概略図。
【符号の説明】
１…廃触媒、２…切断用歯車状上ローラ、３…円筒状下ローラ、４…密閉容器、５…回転体、６…回転刃。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for recovering a catalyst component from a waste catalyst, and more particularly, a method and apparatus for physically selectively recovering a catalyst component from a waste catalyst composed of inorganic fibers and a catalyst component. Method and apparatus for recovering catalyst components from waste catalyst, which can reduce the proportion of mixed inorganic fibers as much as possible, and can effectively carry out chemical inorganic fiber separation treatment performed in the subsequent process on the recovered catalyst components About.
[0002]
[Prior art]
In recent years, in order to prevent environmental pollution, it has been a worldwide movement to prohibit the disposal of various used products as they are, and to collect and reuse as much as possible.
Conventionally, as a method of recovering a catalytically active component from a used waste catalyst, for example, a method of recovering molybdenum oxide from a catalyst containing an oxide of molybdenum (Japanese Patent Laid-Open No. 10-202114) or a raw material is recovered from a waste catalyst. A method (Japanese Patent Publication No. 58-29143) is known. The former is a method in which molybdenum oxide is changed to molybdic acid vapor with water vapor at 500 to 800 ° C., and then cooled to 500 ° C. or lower and recovered as molybdenum oxide or molybdic acid. The latter is a catalyst with a mineral acid such as sulfuric acid. Is dissolved and then neutralized with an alkaline solution such as aqueous ammonia, and the precipitate is filtered and washed to be reused as a catalyst.
[0003]
However, when inorganic fibers are added to the catalyst in order to improve the mechanical strength, the inorganic fibers are physically separated from the catalyst component part in advance, and chemical recovery treatment is performed only on the catalyst component part after separation. It is desirable to do.
For example, an example of a raw catalyst that is a source of waste catalyst is water added to a catalyst component containing titanium, molybdenum, and vanadium, and then mixed with inorganic fibers (trade name: Kao wool) mainly composed of silica / alumina. The applied catalyst raw material paste is applied to a woven fabric made of E glass fibers, coated with the E glass fiber woven fabric, and then rolled into a predetermined shape with a pair of upper and lower press dies, after drying, 300 to 500 There is a plate-like catalyst calcined at a calcining temperature of about ° C.
[0004]
In this case, the E glass fiber woven fabric gives mechanical strength to the plate-shaped catalyst formed in a predetermined shape, for example, a predetermined wave height and a predetermined wave shape, and silica / alumina mixed in the catalyst component paste is used. The inorganic fiber as the main component improves the physical and mechanical strength of the catalyst component part applied and supported on the woven fabric.
The inorganic fiber woven fabric only needs to give mechanical strength to the plate-like catalyst body, and may be a network of inorganic fibers or an inorganic fiber array arranged in parallel in the vertical or horizontal direction. Good.
[0005]
[Problems to be solved by the invention]
Chemical recovery treatment compared to the recovered catalyst component when the ratio of inorganic fiber woven fabric, etc. contained in the whole catalyst is high, as in the case of a catalyst that is calcined after rolling the catalyst paste onto the inorganic fiber woven fabric, etc. In consideration of the processing cost of chemical catalyst component recovery, the total amount of the waste catalyst to be input to the process needs to be reduced in advance by another simple method.
[0006]
As a method for separating the inorganic fiber portion from the catalyst component portion in advance, it is conceivable that the waste catalyst is crushed into small pieces and classified by a classifying means to separate the catalyst component portion and the inorganic fiber portion. As a result of these experiments, when the waste catalyst containing inorganic fiber woven fabric, etc. is pulverized with a high-speed mixer or ball mill, etc., the inorganic fiber woven fabric whose toughness is reduced due to the reaction with the sulfate radical in the catalyst component and the catalytically active component Was easily broken and powdered and mixed with the catalyst component powder, it was found that even if such powder was classified, it was impossible to effectively remove the inorganic fiber portion from the catalyst component.
The object of the present invention is to solve the above-mentioned problems of the prior art, reduce inorganic fibers contained in the catalyst component recovered from the waste catalyst as much as possible, and improve the catalyst component recovery rate from the catalyst to recover the catalyst component It is to provide a method and apparatus.
[0007]
[Means for Solving the Problems]
The invention claimed in the present application in order to solve the above problems is as follows.
(1) After cutting the waste catalyst containing the catalyst component and the inorganic fiber into small pieces, the catalyst component and the inorganic fiber are separated and the catalyst component is pulverized by colliding this with a rotary impactor installed in the container. A method for recovering a catalyst component from a waste catalyst, wherein the catalyst component is recovered by classifying them.
(2) Cutting the waste catalyst having the catalyst component supported on the inorganic fiber cloth into small pieces, then humidifying the small pieces and causing the humidified waste catalyst small pieces to collide with a plate-like or rod-like rotating body provided in the container. Thus, after separating the catalyst component and the inorganic fiber cloth, the catalyst component is separated and collected by a classifying means, and the catalyst component is recovered from the waste catalyst.
[0008]
(3) A set of rollers composed of a roller having a gear-shaped cross section and a cylindrical roller, which is a used waste catalyst of a plate-like catalyst obtained by drying and firing a catalyst component paste applied to an inorganic fiber cloth. After separating the catalyst component and the inorganic fiber cloth body by cutting them into small pieces of a predetermined size by allowing them to pass between them and colliding the waste catalyst after cutting with a plate-like or rod-like rotating body installed in the container. A method for recovering catalyst components from a waste catalyst, wherein the catalyst components are sorted and recovered by classifying them with a sieve having a predetermined opening.
[0009]
(4) A combination of a roller having a gear-like cross section and a cylindrical roller, or a gear-like roller and a gear-like shape, in which the waste catalyst having the catalyst component supported on the inorganic fiber for reinforcing the catalyst is cut into small pieces having a predetermined dimension or less. A cutting machine composed of a combination with a roller and a waste catalyst piece after cutting are accommodated, and the piece is hit from the catalyst component to prevent the inorganic fiber body from being crushed. Mixer means comprising a rotary impacting body in a container, and classification means for classifying a mixture of the catalyst component and the inorganic fiber body treated by the mixer means to selectively collect the catalyst component. An apparatus for recovering catalyst components from waste catalyst.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
In the method of the present invention, a used waste catalyst composed of a catalytically active component part and an inorganic fiber part is cut into small pieces, for example, several millimeters square, and then collided with a rotating body installed in a sealed container, and the impact of the inorganic fiber and The catalyst active component powder is separated, and the catalyst component powder having a predetermined particle size or less is classified and separated from the obtained mixture of the catalyst active component and the inorganic fiber to remove the inorganic fiber and recover the powder having a high content of the catalyst component. Is.
[0011]
The waste catalyst is efficiently cut into small pieces by passing between a pair of rollers having a gear-shaped cross section or between a roller having a gear-shaped cross section and a cylindrical roller. Further, when the small pieces crushed by the rotating body are classified with a mesh having a pore diameter of about 0.1 to 2 mm, the inorganic fiber and the catalyst component can be separated most effectively.
In the present invention, after cutting, if the strength of the inorganic fibers contained is increased by wetting or moistening the waste catalyst before crushing, and if the inorganic fibers are less likely to break during crushing, the catalyst portion and the inorganic fiber portion Separation efficiency can be increased.
By reducing the proportion of the inorganic fibers in the waste catalyst powder in this way, the volume of treatment in the chemical separation step of silica and alumina (the main component of kao wool fibers) in the inorganic fibers to be performed later is reduced. The
[0012]
The present invention is characterized in that in order to remove the inorganic fibers contained in the waste catalyst by a simple method, the catalyst is peeled off from the inorganic fibers by first cutting the waste catalyst into small pieces, colliding with a rotating body and crushing. . The rotating body is preferably a plate-shaped or rod-shaped body without a cutting blade. Normally, when powders such as catalysts are classified and recovered, powders crushed with a high-speed mixer or ball mill are classified. However, when waste catalysts containing inorganic fibers are crushed by these methods, sulfate radicals in the catalyst components and catalytic activity are classified. Inorganic fibers whose toughness is reduced by reaction with the components are easily broken and become powdery. Even if such powder is classified, it has been impossible to effectively remove inorganic fibers from the catalyst component.
[0013]
When the size of the waste catalyst piece is large, if it is sufficiently crushed until it becomes a small piece, a part of the inorganic fiber is crushed in the process. In order to prevent this, the catalyst can be peeled off with a slight impact by cutting the waste catalyst into small pieces of about several mm square. In addition, it is difficult to classify the fiber that has been powdered and the catalyst component powder, and it is necessary to use a chemical separation method.
[0014]
In the present invention, in order to crush the spent catalyst to a certain size, a roller having a gear-shaped cross section that can apply a shearing force at regular intervals and a pair of rollers consisting of a cylindrical roller circumscribing the roller, or both The most effective method is to pass the spent catalyst between a pair of rollers having a gear-shaped cross section.
In addition, since inorganic fibers have higher toughness in proportion to moisture, the catalyst components can be separated and recovered without breaking the inorganic fibers by applying an impact after putting the waste catalyst pieces into a hygroscopic or water-absorbing state. Can do.
[0015]
【Example】
Next, the present invention will be described in more detail with reference to the drawings.
The spent waste catalyst used in the embodiment of the present invention is a catalyst part (a catalyst part comprising an oxide having a molar ratio of titanium, molybdenum and vanadium of 94: 5: 1 and silica alumina fiber (trade name: Kao Wool)). : 20% by weight of the entire catalyst part) and two 0.6mm thick E glass cloth woven cloth parts sandwiching the catalyst from the upper and lower surfaces. is there. Since 22% of the total weight is woven fabric, the fiber is about 38% of the total. The above plate-like catalyst is prepared by supplying a paste obtained by adding water and kao wool to a catalyst component and mixing them between two upper and lower E glass cloths, applying them by rolling, drying and firing.
[0016]
Example 1
The above-mentioned waste catalyst is passed through a pair of cutting machines comprising a cutting gear-like upper roller 2 shown in FIG. 1 and a cylindrical lower roller 3 circumscribing it to form a plate-like catalyst having a width of 5 mm or less. The plate-shaped catalyst having a width of 5 mm or less was supplied again so that the length direction intersects the axial direction of the gear roller 2, for example, orthogonally, and cut into small pieces of 5 mm square or less. The size of the small pieces of the waste catalyst can be changed by changing the circumferential pitch of the gear portion of the cutting gear roller.
[0017]
Next, this was supplied into a mixer having a plate-like or rod-like rotating body 5 as shown in FIG. 2 in a sealed container 4 and crushed for about 10 seconds. The crushed powder was classified with a sieve having a pore size (opening) of 0.5 mm, and separated into an inorganic fiber cloth part and a catalyst component part. The shape of the rotating body 5 is not limited to a plate-shaped body or a rod-shaped body, it is used to strike a small piece of waste catalyst, and the inorganic fiber woven fabric is peeled off from the catalyst component portion without being pulverized into powder. And what is necessary is just to grind | pulverize a catalyst component part into the powder below a predetermined magnitude | size.
[0018]
Example 2
The waste catalyst 1 was cut to 5 mm square or less by the same method as in Example 1, and the obtained waste catalyst piece was mixed with 20% by weight of water, and then crushed and classified under the same conditions as in Example 1.
[0019]
Comparative Example 1
The waste catalyst 1 was cut into 5 mm square or less by the same method as in Example 1. This was replaced with a plate-like rotating body, and the mixture was supplied to the same mixer as in Example 1 except that the rotating blade 6 was provided, and crushing was performed for 30 seconds until there were no small pieces of waste catalyst. The obtained crushed material was classified with a sieve having a pore size of 0.5 mm in the same manner as in Example 1.
The concentration of calcium (contained in E glass) in the catalyst component powders recovered in Examples 1 and 2 and Comparative Example 1 was compared and used as an index of change in the amount of inorganic fibers. The results are shown in Table 1. The measurement was performed by fluorescent X-ray analysis.
[0020]
[Table 1]

As shown in the above table, it was confirmed that in Examples 1 and 2, the proportion of the inorganic fiber woven fabric in the recovered catalyst powder was significantly reduced as compared with Comparative Example 1.
[0021]
【The invention's effect】
According to the present invention, the catalyst component raw material can be efficiently recovered from the waste catalyst containing inorganic fibers, and the catalyst that has been conventionally discarded can be reused.
[Brief description of the drawings]
FIG. 1 is a schematic view of an apparatus for converting a waste catalyst used in Examples into small pieces.
FIG. 2 is a schematic view of a mixer for crushing spent catalyst pieces used in Examples.
FIG. 3 is a schematic view of a mixer for crushing a waste catalyst piece using a rotary blade used in a comparative example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Waste catalyst, 2 ... Cutting gear-shaped upper roller, 3 ... Cylindrical lower roller, 4 ... Sealed container, 5 ... Rotating body, 6 ... Rotary blade.

Claims (4)

After cutting the waste catalyst containing the catalyst component and inorganic fiber into small pieces, the catalyst component and the inorganic fiber are separated while being collided with a rotary impactor installed in the container, and the catalyst component is pulverized and classified. And then recovering the catalyst component from the waste catalyst. By cutting the waste catalyst in which the catalyst component is supported on the inorganic fiber cloth body into small pieces, then humidifying the small piece, and impinging the humidified waste catalyst small piece on a plate-like or rod-like rotating body provided in the container, A method for recovering a catalyst component from a waste catalyst, comprising separating the catalyst component and the inorganic fiber cloth and then separating and recovering the catalyst component by classification means. Passing the used waste catalyst of the plate catalyst formed by drying the catalyst component paste coated on the inorganic fiber cloth and firing it between a pair of rollers consisting of a roller having a gear-shaped cross section and a cylindrical roller After separating the catalyst component and the inorganic fiber cloth body by colliding with a plate-like or rod-like rotating body installed in the container, the waste catalyst after cutting is cut into small pieces of a predetermined size. A method for recovering a catalyst component from a waste catalyst, wherein the catalyst component is selectively recovered by classification with a sieve having a predetermined opening. A combination of a roller having a gear-shaped cross section and a cylindrical roller, or a combination of a gear-shaped roller and a gear-shaped roller, which cuts a waste catalyst in which a catalyst component is supported on an inorganic fiber for catalyst reinforcement, into pieces having a predetermined size or less. A rotary blower that accommodates a cutting machine composed of a combination and a waste catalyst piece after cutting, peels it off from the catalyst component while giving a blow to the piece to prevent the inorganic fiber body from being broken, and crushes the catalyst component Waste comprising: mixer means provided with a body in a container; and classifying means for classifying a mixture of the catalyst component and inorganic fiber body treated by the mixer means to selectively collect the catalyst component Catalyst component recovery device from the catalyst.

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