KR20020010173A - A Method for Rejuvenating Hydrocarbon Conversion Catalyst - Google Patents

Abstract

The present invention relates to a method for separating a catalyst to be regenerated from a waste catalyst for hydrocarbon conversion process by magnetic screening, and regenerating it in an environmentally friendly method. The method for regenerating the spent catalyst for the hydrocarbon conversion process of the present invention comprises the steps of: separating the regenerated catalyst from the spent catalyst for the hydrocarbon conversion process using a magnetic screening method; The separated catalyst is saturated with one or more gases selected from the group comprising 1 to 20 atmospheres of N ₂ , He, Cl ₂ , CCl ₄ , CO, H ₂ S, H ₂ and O ₂ gases, and 300 to 1,000 Heat treatment at 30 ° C. for 30 minutes to 6 hours; Washing the heat treated catalyst with an aqueous washing solution containing an organic acid, an inorganic acid, an oxidizing agent or a reducing agent; And recovering the metal from the wash liquid using a precipitant or an electrical method. According to the present invention, it can be economically regenerated using the magnetic screening method, and it does not use any toxic gas, so it does not incur the cost or operating cost of a special operation facility, and does not generate a large amount of toxic wastewater including metal chlorides and bases. Do not. In addition, since the metal is easily recovered from the washing liquid, not only heavy metal-containing waste water is generated, but also the washing liquid can be reused.

Description

A Method for Rejuvenating Hydrocarbon Conversion Catalyst

The present invention relates to a method for regenerating a catalyst for a hydrocarbon conversion process. More specifically, the present invention relates to a method of separating a catalyst to be regenerated from a spent catalyst for hydrocarbon conversion process by magnetic screening, and recycling it in an environmentally friendly manner.

In the process of producing gasoline, a typical hydrocarbon conversion process, a large amount of catalyst is used in fluid catalytic cracking (FCC), resid fluid catalytic cracking (RFCC), or desulfurization. It is used. A large amount of waste catalyst generated in such a process is mainly recycled to construction materials such as landfill or cement, but the most preferable method of recycling the electric waste catalyst is to recycle the waste catalyst and use it as a catalyst again.

Recycling of such spent catalysts has been studied in various ways. The most commonly used method of regenerating spent catalysts includes catalysts and metals that cannot be used because the metals contained in the spent catalysts are contained, Including the metal component to separate the reusable catalyst particles, and reuse the catalyst particles that can be reused. For electrical separation, flotation using density and magnetic separation using magnetic properties of the metals involved are commonly used. Among these, since the flotation uses water or a solvent, the cost of treating the catalyst is additionally increased, and the steps are complicated. In recent years, magnetic screening is mainly used. U. S. Patent No. 4,406, 773 discloses a method for separating and reusing a catalyst portion retaining activity in a spent catalyst by magnetic screening, but it does not regenerate the lost portion. There was a disadvantage that it can not provide.

On the other hand, since most of the metal is deposited on the catalyst in the part where activity is lost, efforts have been made to regenerate the catalyst by removing the metal of this part. As a result of these efforts, a chloride process has been developed in which the catalyst is treated with chlorine to produce metal chlorides and washed. The electric method is very effective in removing metals, but the use of toxic chlorine gas can put the equipment and the operator at risk. Waste water containing a large amount of chlorine and metals washed with chloride is generated. In this case, the active ingredient of the catalyst can be destroyed, so it has a disadvantage of requiring a condition sensitive to active regeneration.

Thus, U.S. Patent No. 4,267,032 discloses a metal removal rate of Ni 86-92% (w / v), V 49-51% (by using two washing methods, oxidative washing and reducing washing, by pre-treatment and hydrogen sulfide treatment). w / v) and Fe 53-58% (w / v) metal removal method, US Pat. No. 4,686,197 discloses the fired waste catalyst through the chlorination reaction at 371 ℃ using water, oxidative washing and reduction washing Using a method of washing eggplant, a metal removal method having a metal removal rate of Ni 70 to 90% (w / v), V 50 to 80% (w / v) and Fe 30 to 75% (w / v) has been disclosed. , U. S. Patent No. 5,155, 073 discloses the removal efficiency of metals with Ni 95% (w / v), V 53% (w / v), Fe 77% (w / v) by sulfiding the catalyst with hydrogen sulfide prior to the chlorination reaction. Japanese Patent Application Laid-Open No. 58-202049 discloses a method in which the metal removal rate is 57% (w / v) using Ni chloride using carbon tetrachloride and hexachloroethane. As described above, the electric method is carried out by reducing the catalyst calcined at 650 to 800 ° C. with hydrogen at that temperature and contacting a gas of carbon tetrachloride, hexachloroethane at 300 to 450 ° C., and 200 ° C. using methanol or water. As a method of washing at 10 atmospheres, only vanadium (V) could be selectively removed depending on the conditions.

However, the above-mentioned regeneration methods must contain a large amount of additives in the washing liquid, the process of treating them is complicated, and the specific treatment method for the heavy metal waste water generated inevitably is not described. Since the wastewater treatment apparatus has to be installed, there is a disadvantage in that the environmental problems inevitably generated during the regeneration of the catalyst and the costs associated with the treatment thereof are high enough to be similar to the new production costs.

Therefore, there is a constant need to develop a method for regenerating the waste catalyst for the hydrocarbon conversion process in an environmentally friendly manner.

Accordingly, the present inventors have made diligent efforts to establish a technology for regenerating the waste catalyst for hydrocarbon conversion process in an environmentally friendly manner, and heat treated the catalyst separated by the magnetic separation method under saturated gas and various organic acids, After washing with an aqueous washing liquid containing an inorganic acid, an oxidizing agent, or a reducing agent, and then recovering the metal from the washing liquid using a precipitant or an electrical method, it was confirmed that the catalyst for hydrocarbon conversion process can be environmentally regenerated. To complete.

After all, the main object of the present invention is to provide an environmentally friendly method for regenerating spent catalyst for hydrocarbon conversion process.

1 is a schematic diagram showing a step of screening a waste catalyst using a continuous magnetic separator.

The method for regenerating the spent catalyst for the hydrocarbon conversion process of the present invention comprises the steps of: separating the regenerated catalyst from the spent catalyst for the hydrocarbon conversion process using a magnetic screening method; The separated catalyst is saturated with one or more gases selected from the group comprising 1 to 20 atmospheres of N ₂ , He, Cl ₂ , CCl ₄ , CO, H ₂ S, H ₂ and O ₂ gases, and 300 to 1,000 Heat treatment at 30 ° C. for 30 minutes to 6 hours; Washing the heat treated catalyst with an aqueous washing solution containing an organic acid, an inorganic acid, an oxidizing agent or a reducing agent; And recovering the metal from the wash liquid using a precipitant or an electrical method.

Hereinafter, the method for regenerating the spent catalyst for hydrocarbon conversion process of the present invention will be described in more detail by dividing the process.

Step 1 : Separation of Regenerated Catalyst

The magnetic separation method is used to separate the regenerated catalyst from the spent catalyst for the hydrocarbon conversion process. The magnetic separation is performed by using a magnetic separation device, which uses a permanent or electromagnet using rare earth metal to separate the catalyst. The magnetic force used is preferably 6,000 to 50,000 gauss, more preferably 8,000 to 20,000 gauss, most preferably 12,000 gauss, and is not limited to forms such as suspended, drum, lattice, and pulleys. Do not.

Second Process : Heat Treatment of Regenerated Catalyst

The separated catalyst is saturated with one or more gases selected from the group comprising 1 to 20 atmospheres of N ₂ , He, Cl ₂ , CCl ₄ , CO, H ₂ S, H ₂ and O ₂ gases, and 300 to 1,000 Heat-treat at 30 ° C. for 30 minutes to 6 hours: At this time, the gas used according to the catalyst may be used alone or in admixture with two or more other gases, and may be used by saturating the electric gas in the gas phase, but in the gas phase The content of the gas is not limited. The pressure of the electric gas is preferably 1 to 20 atm, more preferably 7 to 14 atm, most preferably 10 atm, preferably 300 to 1,000 ° C, more preferably 500 to 800 ° C, Most preferably, the heat treatment is performed at a temperature of 650 ° C. for 30 minutes to 6 hours, more preferably 1 to 3 hours, and most preferably 2 hours. In addition, the heat treated catalyst is preferably not cooled, but may be cooled depending on the catalyst.

3rd step : washing the heat treatment catalyst

The heat treated catalyst is washed with an aqueous washing solution containing an organic acid, an inorganic acid, an oxidizing agent, or a reducing agent: wherein the organic acid used may be lactic acid, acetic acid, succinic acid, oxalic acid, citric acid, and the like, and the inorganic acid may be HCl, HNO ₃ , H _2. SO ₄ . H ₃ PO ₄ or the like may be used, H ₂ O ₂ or O ₃ may be used as the oxidizing agent, SO _2, metal sulfide, or the like may be used as the reducing agent. In addition, the water-soluble washing liquid contains an electrical material of 0.01 to 10% (w / v) relative to the water-soluble washing liquid, it is particularly preferable that the content is 1% (w / v). The composition and the mixing ratio of the material contained in the aqueous washing solution are not particularly limited, but depend on the type of catalyst. The temperature of the water-soluble washing liquid is preferably 15 to 100 ° C, but more preferably 50 to 80 ° C, most preferably 65 ° C, and the pressure of the gas phase when washing with the water is preferably 1 to 20 atm. More preferably, it is 1-3 atmospheres, Most preferably, it is 1 atmosphere. The washed catalyst is dried and then reused.

Fourth Step : Recovery of Metal

The metal is recovered from the wash liquor using a precipitant or an electrical method: precipitants used are Na ₂ CO ₃ , Na ₂ SO ₄ , NaHCO ₃ , (NH ₄ ) ₂ SO ₄ , (NH ₄ ) ₂ CO ₃ In the case of using the electric method, the metal is attached to the electrode by recovering the metal by applying a voltage of 1 to 100 V at a normal temperature and normal pressure for 30 minutes to 90 minutes.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are only for illustrating the present invention in more detail, it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples in accordance with the gist of the present invention. .

Example 1 Separation of Waste Catalyst Using Permanent Magnet

Residual fluid catalytic cracking (RFCC) containing on average 6,200ppm, V 5,600ppm and Fe 3,600ppm metals using a continuous magnetic separator using 12,000 gauss magnetic drum-type permanent magnets 5 kg of the waste catalyst discharged from the process was separated (see FIG. 1). In Fig. 1, reference numeral 1 denotes a roller composed of a magnet, reference numeral 2 denotes a rotational direction of the belt and a direction of magnetic force, and reference numeral 3 denotes a belt. When the waste catalyst is introduced into the belt of the apparatus as shown in FIG. 1 and the roller formed of the magnet is rotated, the waste catalysts introduced into the belt fall. The waste catalyst having a difference in magnetization according to the amount of metal contained therein is Depending on the degree of magnetization, the drop position will vary. As a result of separating these into five fractions, the most highly magnetized fractions contained metals containing 8,000 ppm Ni, V 6,200 ppm and Fe 4,200 ppm. The fractions with the lowest magnetization were Ni 5,200 ppm, V 5,200 ppm and Fe 3,200. It contained ppm metal. The most susceptible fraction was about 5% (w / v) of all samples, and the least susceptible fraction was 60% (w / v).

Example 2 Separation of Waste Catalyst Using Electromagnet

5 kg of the waste catalyst was separated using a combination magnetic separator using a magnetic drum type and a suspended type electromagnet. Using the same method as in Example 1, all five fractions were used. As a result, the metals contained in the highest magnetization fraction had Ni 8,200 ppm, V 6,300 ppm and Fe 4,400 ppm, and the fraction having the lowest magnetization was Ni 4,500. It contained metals of ppm, V 4,200 ppm and Fe 2,800 ppm. Compared with Example 1, it was found that the efficiency of separation can be improved by using an electromagnet having a high magnetic force.

Example 3 Comparison of Activity of Separated Catalysts (Ⅰ)

To determine the difference in catalytic activity of each fraction of Example 2, each fraction obtained in Example 2 was subjected to the micro activity test (MAT) described in the American standard testing method (ASTM) D5154. Was carried out to measure their hydrocarbon conversion activities and to compare them. The conversion rate of the highest magnetization fraction was 76.2%, and the yield of hydrogen was 0.8920% and the yield of coke was 10.3420%. In addition, the conversion rate of the fraction with the lowest magnetization was 76.7%, the yield of hydrogen was 0.3870%, the yield of coke was found to be 8.9218%, it was confirmed that the physical properties of the product is reduced by reducing the content of metal.

Example 4 Regeneration of Spent Catalyst Using H ₂ S Gas

Of the fraction of Example 2, 1 kg of the highest magnetization part was regenerated using a regeneration method to remove metal. The metals included in the spent catalyst were Ni 8,200 ppm, V 6,500 ppm and Fe 4,400 ppm.

Hydrogen gas containing 9.62% H ₂ S gas at 400 ^° C / min is charged at 800 ^o C, and heat treated at 10 atmospheres for 2 hours, followed by 5% of 1% citric acid solution (w / v) at atmospheric pressure. Washed with. The washed catalyst was regenerated by drying at 80 ^° C. for 8 hours. The regenerated catalyst contained 1400 ppm Ni, 3200 ppm V and 2400 ppm Fe.

Example 5 Regeneration of Spent Catalyst Using Oxygen

The waste catalyst used in Example 4 was heated to 400 ml / min to saturate with oxygen at 700 ^° C., and then heat-treated for 3 hours while maintaining 10 atm, followed by 5 L of 0.05% HNO ₃ solution (w / v) at atmospheric pressure. Washed with. The washed catalyst was regenerated by drying at 80 ^° C. for 8 hours. The regenerated catalyst contained metals of Ni 7,800 ppm, V 2,800 ppm and Fe 4,100 ppm.

Example 6 Comparison of Activity of Separated Catalysts (II)

The hydrocarbon conversion activities of the regenerated catalysts of Examples 3 and 4 were measured by the method of Example 3 and these were compared. In Example 3, the conversion of the regenerated catalyst was 81.1%, the yield of hydrogen was 0.1893%, and the yield of coke was found to be 9.1324%. In addition, it was found that the conversion rate of the regenerated catalyst in Example 4 was 79.6%, the yield of hydrogen was 0.2238%, and the yield of coke was 8.8724%.

Example 7 Recovery of Metal Using Precipitant

In order to recover the metal components included in the washing solution used in Example 4, 5 g of sodium carbonate was added to 5 L of the washing solution to precipitate. The metal components included in the washing solution were Ni 78 ppm, V 39 ppm and Fe 51 ppm. In addition, since the maximum precipitation pH of Ni is 9.5, the maximum precipitation pH of Fe is 6, and the maximum precipitation pH of 8.0 is 8.0, Ni, Fe, and V dissolved in the washing solution were separated by adjusting the pH of the washing solution. After separating the metal carbonate precipitated at each corresponding pH as a filter, a metal component of Ni 7ppm, V 2ppm and Fe 3ppm remained in the washing solution.

Example 8 Recovery of Metal Using Electrical Method

An electrical method was used to recover the metal components included in the wash solution used in Example 5. Metal components included in the washing solution were Ni 8 ppm, V 42 ppm and Fe 7 ppm. A voltage of 10 V was applied to the cleaning liquid by using two carbon electrodes of the positive electrode and the negative electrode. After 1 hour, the carbon electrode turned silver white, and the metal components included in the cleaning solution were Ni 3 ppm and V 4 ppm. Fe was 2 ppm.

Through the method of Examples 7 to 8, the heavy metal which can be an environmental pollutant without special equipment can be easily purely separated and used in other processes, and since most of the metal components in the washing liquid have been recovered, the washing liquid can be used again. I learned.

As described and demonstrated in detail above, the present invention is to separate the catalyst from the spent catalyst for the hydrocarbon conversion process by magnetic separation method, and heat-treated it under conditions saturated with various gases, and then water-soluble including various organic acids, inorganic acids, oxidizing agents, or reducing agents. The present invention provides a method of regenerating a waste catalyst through an environmentally friendly method of washing with a washing liquid and then recovering metal from the washing liquid using a precipitant or an electrical method. According to the present invention, it can be economically regenerated using the magnetic screening method, and it does not use any toxic gas, so it does not incur the cost or operating cost of a special operation facility, and does not generate a large amount of toxic wastewater including metal chlorides and bases. Do not. In addition, since the metal is easily recovered from the washing liquid, not only heavy metal-containing waste water is generated, but also the washing liquid can be reused.

As described above in detail specific parts of the present invention, it is apparent to those skilled in the art that such specific descriptions are merely preferred embodiments, and thus the scope of the present invention is not limited thereto. something to do. Thus, the substantial scope of the present invention will be defined by the appended claims and their equivalents.

Claims (9)

(Iii) separating the regenerated catalyst from the spent catalyst for the hydrocarbon conversion process by using a magnetic screening method; (Ii) saturating the separated catalyst with one or more gases selected from the group comprising 1-20 atmospheres of N ₂ , He, Cl ₂ , CCl ₄ , CO, H ₂ S, H ₂ and O ₂ gases, Heat treatment at 300 to 1,000 ° C. for 30 minutes to 6 hours; (Iii) washing the heat treated catalyst with an aqueous washing solution containing an organic acid, an inorganic acid, an oxidizing agent or a reducing agent; And, (Iii) a method for regenerating a catalyst for a hydrocarbon conversion process, comprising the step of recovering a metal from the washing liquid using a precipitant or an electrical method. The method of claim 1, (Iii) The magnetic screening method of the process has a magnetic force of 6,000 to 50,000 gauss. Characterized in that it is performed using an electromagnet or permanent magnet Regeneration method of catalyst for hydrocarbon conversion process. The method of claim 1, (Iii) The organic acids contained in the aqueous wash solution of the process are lactic acid, acetic acid, succinic acid, Oxalic acid or citric acid, the inorganic acid is HCl, HNO ₃ , H ₂ SO ₄ or H ₃ PO ₄ , The oxidizing agent is H ₂ O ₂ or O ₃ , the reducing agent is SO ₂ or metal sulfide, 0.01 to 10% (w / v) relative to the wash solution, characterized in that Regeneration method of catalyst for hydrocarbon conversion process. The method of claim 1, (Iii) washing of the process using a water-soluble washing solution of 15 to 100 ℃ 1 Characterized in that it is carried out at a washing pressure of 20 to 20 atm Regeneration method of catalyst for hydrocarbon conversion process. The method of claim 1, (Iii) drying and regenerating the catalyst washed by the process. Characterized Regeneration method of catalyst for hydrocarbon conversion process. The method of claim 1, (Iii) Precipitants in the process are Na ₂ CO ₃ , Na ₂ SO ₄ , NaHCO ₃ , (NH ₄ ) ₂ SO ₄ and (NH ₄ ) ₂ CO ₃ Characterized in that the one selected from the group consisting Regeneration method of catalyst for hydrocarbon conversion process. The method of claim 1, (Iii) The electrical method of the process is 1-100V It is carried out by applying a voltage for 30 minutes to 90 minutes Regeneration method of catalyst for hydrocarbon conversion process. Catalyst for hydrocarbon conversion process, regenerated by the process of claim 1. A continuous magnetic separator using a magnetic drum-type permanent magnet is used to separate the regenerated catalyst from the spent catalyst for the residual oil-contact catalytic cracking process, and is electrically separated while maintaining 10 atm with a hydrogen gas containing H ₂ S gas. After the catalyst is heat-treated at 800 ^° C for 2 hours, the method of regenerating the waste catalyst for the residue oil-flow catalytic catalytic process comprising the step of regenerating by washing the heat-treated catalyst with an aqueous citric acid solution at normal pressure.