JPS63197543A - Adsorbent for recovering group viii noble metallic complex and recovering method - Google Patents

Abstract

PURPOSE:To obtain an adsorbent for recovery capable of recovering group VIII noble metallic complex nearly quantitatively by depositing organic phosphorus compd. furthermore on activated carbon previously subjected to oxidizing treatment. CONSTITUTION:Firstly activated carbon is preferably oxidized with nitric acid or oxidized with air or oxygen under high temp. Then an adsorbent for recovering group VIII noble metallic complex is obtained by depositing organic phosphorus compd. (e.g. triphenylphosphite and triphenylphosphine or the like) on activated carbon subjected to oxidizing treatment. Further activated carbon before oxidizing treatment preferably has a fine pore distribution not less than 0.35ml/g fine pore volume in a range of 20-300Angstrom fine pore diameter. The deposited amount of organic phosphorus compd. for activated carbon subjected to oxidizing treatment is preferably set at a range of 0.1-5m-mol/g.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an organic liquid containing a group Ⅰ noble metal compound complex (
For example, the present invention relates to an adsorbent for recovering a group (I) noble metal complex from a reaction solution of an unsaturated compound (hydroformylation reaction), and further relates to a method for recovering a group (I) noble metal complex from the above-mentioned organic liquid.

From the prior art, a soluble complex of a Group I noble metal compound and an organic phosphorus compound is used as a catalyst in the hydroformylation or hydrocarboxylation reaction of olefins.

Since the catalyst is uniformly dissolved in the reaction product, it is necessary to separate and recover the expensive catalyst and return it to the reaction system.

When the reaction product has a low boiling point, it is possible to separate the reaction product and the catalyst liquid by distillation and reuse the catalyst liquid in the next reaction.

However, in this reaction, various high-boiling by-products are produced, so in order to avoid accumulation of high-boiling by-products in the reaction system due to circulation of the catalyst liquid, high-boiling by-products are removed from the reaction system by distillation. It is necessary. Since the removed high-boiling byproducts contain expensive Group III noble metals,
It is necessary to collect this efficiently.

However, at high temperatures of 150°C or higher, the Okuki complex undergoes thermal deterioration and its catalytic activity decreases. In some cases, it may be necessary to carry out a special activation treatment to activate the separated catalyst.

If the reaction product has a high boiling point, it can be removed by a method other than distillation, such as adsorption or extraction, in the same manner as above.
It is necessary to recover the Group noble metal complex or, if by distillation, to carry out a special activation treatment to activate the separated catalyst.

Conventionally, the following method has been proposed as a method for recovering a soluble complex of a group (I) noble metal compound and an organic phosphorus compound or a group (I) noble metal from a reaction solution used in the hydroformylation reaction of an olefin.

JP-A No. 49-121793 discloses that after hydroformylation of butene and tonos reflexine is carried out using a rhodium-tertiary phosphine complex catalyst, the low-boiling point portion is separated by distillation, and then the high-boiling point distillation residue is obtained. As a method for separating a rhodium-tertiary phosphine complex catalyst from A method is shown in which high-boiling organic distillation residues are washed away from the adsorbent using a group hydrocarbon solvent, and the catalyst adsorbed on the adsorbent is further eluted using a polar solvent containing a small amount of tertiary amine. There is.

Japanese Patent Publication No. 53-3993 discloses that in adsorbing and separating a group (I) noble metal from an organic liquid containing a group (I) noble metal complex using activated carbon, methanol is allowed to coexist in the organic liquid. . In this method, for example, propylene is subjected to a hydroformylation reaction in the presence of a rhodium-phosphorous compound complex catalyst, and then the aldehyde product is separated by distillation, and an organic liquid containing a high-boiling by-product and a catalyst is produced. When carrying out a hydroformylation reaction by charging rhodium into a reactor repeatedly as necessary, rhodium can be recovered from an organic liquid containing high-boiling byproducts and a catalyst by adding methanol and activated carbon to the organic liquid to remove the catalyst. This is done by adsorption. It is said that Group Ⅰ noble metals can be recovered from activated carbon after adsorption treatment by conventional methods such as roasting.

Japanese Patent Publication No. 53-3994 discloses the use of activated carbon that has been previously treated with nitric acid when adsorbing and separating group (III) noble metals from an organic liquid containing group (III) noble metal complexes using activated carbon. . In this method, for example, propylene is subjected to a hydroformylation reaction in the presence of a rhodium-phosphorus compound complex catalyst, and then the product aldehyde is separated by distillation, while the aldehyde containing high-boiling by-products and the catalyst is separated by distillation. The organic liquid is added to the activated carbon treated with nitric acid, and methanol is further added to make the activated carbon treated with nitric acid adsorb rhodium. It is said that Group Ⅰ noble metals can be recovered from the nitric acid-treated activated carbon after adsorption treatment by conventional methods such as roasting.

Japanese Patent Publication No. 53-3995 discloses that an alkane having 5 to 14 carbon atoms is used to adsorb and separate a group (III) noble metal from an organic liquid containing a group VIII noble metal complex using activated carbon.
It has been shown that Group I noble metals can be recovered by coexisting a compound selected from alkenes having 6 to 14 carbon atoms, polyhydric alcohols having 2 to 6 carbon atoms, aliphatic carboxylic acids having 2 to 6 carbon atoms, and dioxane. ing. In this method, for example, propylene is subjected to a hydroformylation reaction in the presence of a rhodium-phosphorus compound complex catalyst, and then the aldehyde product is separated by distillation, and the aldehyde is separated by distillation. When the hydroformylation reaction is carried out by repeatedly charging the organic liquid into the reactor as necessary, rhodium can be recovered from the organic liquid containing high-boiling byproducts and catalyst by adding the above-mentioned compound to the organic liquid and adding activated carbon. In addition, this is done by adsorbing a catalyst. Part ■ from activated carbon after adsorption treatment
The collection of family jewelery notifications will be carried out through normal methods such as roasting.

JP-A No. 60-212233 discloses a method for separating and recovering rhodium by extraction with a complexing reagent from the product of oxo synthesis, in which a cationic, anionic or nonionic surfactant is dissolved in an aqueous solution of the complexing agent. A method of adding auxiliaries is shown.

E, J, Dufek and G, R, Li5t.
, Journal of the American
Oil Chetsists” 5ociet7
．． 54. 2713-278 (1137?) describes a method of using an aqueous HCN solution containing triethanolamine as an extractant in extracting rhodium from hydroformylated vegetable oil or its ester.

J, P, Fr1edrich, G, R, Li5
t and V, E.

5obns, Journal of the Ame
rican Oil ChemistS'5ociet
2.50.455-458 (1973), methyl oleate is subjected to a hydroformylation reaction in the presence of triphenyl phosphite and an active rhodium catalyst supported on an alumina support, and then filtered to remove the filtration residue on an alumina support. The filtrate is distilled to separate the hydroformylated methyl stearate and the soluble rhodium catalyst, and the separated soluble rhodium catalyst is combined with the alumina carrier and calcined in a kiln. It has been shown that catalysts on alumina supports activated by calcination can be reused in hydroformylation reactions.

Problems to be Solved by the Invention However, JP-A-49-121 uses an alkaline earth metal silicate such as magnesium silicate as a recovery adsorbent.
According to Publication No. 793, the recovery rate of the catalyst is about 99.5%, but when the present inventors implemented this method, they found that the adsorption properties of the catalyst were extremely poor. There was also a problem in that the elimination properties of the catalyst (soluble complex) were also poor.

Furthermore, when the activated carbon described in Japanese Patent Publication No. 53-3993 or Japanese Patent Publication No. 53-3995 is used as an adsorbent for recovery, the adsorption rate of the Group Ⅰ noble metal complex, which is the catalyst, to the activated carbon is low, and There was a problem in that the desiliconization of the catalyst adsorbed on activated carbon was also poor.

On the other hand, as an adsorbent for recovery,
When using the nitric acid-treated activated carbon described in the publication, although the adsorption rate of group (III) noble metal complexes is excellent, it is difficult to remove the adsorbed group (III) noble metal complexes, and as a result, the overall recovery rate is low. There was a problem that it was inferior.

Journal of the American O
il ChemistS'5ociety, 54.2
78-278 (197?) and JP-A-60-21223
The extraction method described in Publication No. 3 is difficult to adopt industrially due to the insufficient extraction rate of the catalyst and problems in handling HCN.

Journal of the Aa+erican
Oil ChemistS'5ociety, 50.
455-458 (1973)) requires a calcination step at a high temperature (600°C), the recovery rate of the catalyst is about 98%, and the loss of the catalyst cannot be ignored, and the method described in It has not been industrially satisfactory because the organic phosphorus compound added cannot be recovered, the organic phosphorus compound mixes into the product, and the process is complicated.

The present invention is based on extensive research into activated carbon-based adsorbents, with the aim of efficiently recovering a Group II noble metal complex, which is more expensive than an organic liquid containing a soluble complex of a Group III noble metal compound and an organic phosphorus compound. This is what we achieved as a result.

Means for Solving the Problems The adsorbent for recovery of group (I) noble metal complexes of the present invention is made by carrying an organic phosphorus compound on activated carbon that has been previously oxidized.

The method for recovering a group (III) noble metal complex of the present invention includes contacting an organic liquid containing a group (III) noble metal complex with an organic phosphorus compound as a ligand with an adsorbent, thereby recovering the group (III) noble metal complex in the organic liquid. In adsorbing and separating , the adsorbent is characterized in that activated carbon that has been previously oxidized and further supports an organic phosphorus compound is used as the adsorbent.

The present invention will be explained in detail below.

As mentioned above, the recovery adsorbent of the present invention is made by carrying an organic phosphorus compound on activated carbon that has been previously oxidized.

The activated carbon before oxidation treatment has a pore diameter of 20 to 3 ooA.
It has a pore distribution with a pore volume in the range of 0.35 ml/3 or more (in other words, the value obtained by integrating the pore volume of only pores with a pore diameter in the range of 20 to 300 0.35
It is preferable to use activated carbon (having a concentration of at least ml/3); if activated carbon that does not meet this limit is used as a raw material, the adsorption rate of the Group (I) noble metal complex will decrease.

The following method is adopted as an oxidation treatment method for activated carbon.

(a) Method of oxidizing with nitric acid Activated carbon is immersed in a nitric acid aqueous solution and stirred as necessary. The treatment temperature is usually set in the range from room temperature to the boiling point of the nitric acid aqueous solution, and may be cooled if necessary. The processing time is several minutes to several hours. The higher the nitric acid concentration, the lower the treatment temperature or the shorter the treatment time, and the lower the nitric acid concentration, the higher the treatment temperature or the longer treatment time. Practical conditions include a nitric acid aqueous solution concentration of about 10 to 60% by weight or more, a treatment temperature of room temperature to about 90° C. or more, and a treatment time of about 5 minutes to 3 hours or more. For example, when the nitric acid concentration is 60% by weight, the treatment is performed at room temperature for about 5 to 20 minutes, and when the nitric acid concentration is 10% by weight, the treatment is performed at 90° C. for about 3 hours.

After nitric acid treatment, wash with water to remove nitrate ions,
Further dry if necessary.

(b) Method of oxidizing with air or oxygen Activated carbon is oxidized by keeping it under high temperature conditions in air or oxygen atmosphere. The oxidation temperature is usually 300 to 600°C, preferably 350 to 550°C in the case of air, and usually 200 to 45°C in the case of oxygen.
The temperature is selected from the range of 0°C, preferably from 250 to 400°C, and the treatment time is 0.5 to 2 hours.

Among the above oxidation methods, the nitric acid oxidation method is industrially most suitable, and the oxidation method using air or oxygen can also be employed industrially.

As the organic phosphorus compound supported on the oxidized activated carbon, phosphites or phosphines are used.

Examples of the phosphites include trimethyl phosphite, triethyl phosphite, tricyclohexyl phosphite, triphenyl phosphite, chlordiphenyl phosphite, and tetraphenylethylene diphosphite. Particularly suitable are triethyl phosphite and triphenyl phosphite.

Examples of phosphine include trimethylphosphine, triethylphosphine, tributylphosphine, tricyclohexylphosphine, triphenylphosphine, chlordiethylphosphine, tris(aminoamyl)phosphine, tris(N,N-dimethylanilyl)phosphine, tris(0-tolyl) Examples include phosphine, phenyldiisopropylphosphine, phenyldiamylphosphine, methyldiphenylphosphine, dimethylphenylphosphine, ethyldiphenylphosphine, chlordoxylylphosphine, and trianylylphosphine.

The amount of the organic phosphorus compound supported on the oxidized activated carbon is preferably set in the range of 0.1 to 5 mmol/g. If the amount of the organic phosphorus compound supported is too small, the ability to desorb the Group I noble metal complex from the adsorbent will be insufficient, while if the amount supported is too large, the adsorption ability of the Group W noble metal complex to the adsorbent will be reduced. .

As described above, the method for recovering a group (III) noble metal complex of the present invention is performed by bringing an organic liquid containing a group (III) noble metal complex having an organic phosphorus compound as a ligand into contact with an adsorbent. In adsorbing and separating the Group (1) noble metal complex in the organic liquid, the above-mentioned adsorbent is used as the adsorbent, i.e., activated carbon that has been oxidized in advance and further supports an organic phosphorus compound. That is.

A Group Ⅰ noble metal complex having an organophosphorus compound as a ligand can be easily prepared from a Group Ⅰ noble metal compound and an organophosphorus compound such as phosphites or phosphines by a known complex formation method. . In this case, it may further contain a ligand other than the organic phosphorus compound, such as an acetylacetonate group, a cyclopentagenyl group, a carbonyl group, a carboxyl group, a halogen atom, or a hydrogen atom. It is also possible to form a complex by supplying a group (I) noble metal compound and an organic phosphorus compound to the reaction system.

Compounds of Group II noble metals used to form complexes include oxides, chlorides, bromides, and fluorides of Group II noble metals, such as ruthenium, rhodium, palladium, osmium, iridium, and platinum.

Examples include iodides, nitrates, sulfates, acetates, cyanides, hydrides, carbonyl complexes, and amine complexes. Among these, rhodium compounds are particularly important.

Examples of rhodium compounds include rhodium oxide,
Examples include rhodium nitrate, rhodium trichloride, rhodium acetate, rhodium sulfate, rhodium dicarbonyl chloride, and chlorpentaamino rhodium chloride.

As the organic phosphorus compound used to form the complex, the above-mentioned organic phosphorus compounds supported on oxidized activated carbon, that is, phosphites or phosphines, are used. The organic phosphorus compound used to form the complex and the organic phosphorus compound supported on the oxidized activated carbon are
They may be of the same kind or of different kinds, but it is more advantageous to use the same kind of materials.

Examples of organic liquids containing a Group Ⅰ noble metal complex with an organic phosphorus compound as a ligand include olefin hydroformylation reaction liquid, olefin hydrocarboxylation reaction liquid, and olefin, carbonyl compound, and aromatic compound hydrogenation reaction liquid. etc. can be mentioned. Among these, important are reaction solutions containing hydroformylated higher fatty acids or esters thereof obtained by hydroformylation of olefins, particularly higher unsaturated fatty acids or esters thereof.

The above-mentioned adsorbent can be introduced into the organic liquid to adsorb the No. 1 noble metal complex dissolved therein, and then separated from the organic liquid by means such as filtration or centrifugation.

However, industrially, a column is filled with this adsorbent, and an organic liquid such as a hydroformylation reaction solution is supplied to the column and brought into contact with this adsorbent, thereby adsorbing the group (I) noble metal complex. is desirable.

The organic liquid may be passed in either an upward flow or a downward flow, but an upward flow is more efficient because it is less likely to cause drift.

The higher the adsorption temperature in the adsorption step, the greater the amount of group VIII noble metal complex adsorbed, but if it is too high, it may cause deterioration of the group VIII noble metal complex and alteration of the target product contained in the organic liquid. .

Usually it is set at room temperature to around 120°C.

After the Group 1 noble metal complex in the organic liquid introduced into the adsorption tower is adsorbed by the adsorbent, a solvent is flowed through the tower to remove the organic liquid remaining in the tower or attached to the adsorbent. As the solvent, for example, aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, cumene, and diethylbenzene, and aliphatic hydrocarbons such as heptane and hexane are used.

After removing the organic liquid, the desorbed liquid is passed through the column to desorb the group (I) noble metal complex adsorbed on the adsorbent. The desorption liquid is
Although it is preferable to introduce the organic liquid containing the group (I) noble metal complex in the direction of introduction in the previous adsorption operation, it is preferable to introduce the organic liquid in a countercurrent direction, but this is not necessarily the case.

Examples of the removing liquid include ethers such as diethyl ether, tetrahydrofuran, and dioxane, ketones such as acetone, diethyl ketone, and methyl ethyl ketone, methanol,
Polar solvents such as alcohols such as ethanol and impropatol, and esters such as methyl acetate, ethyl acetate, butyl acetate, and amyl acetate are suitable.

In this case, it is preferable to mix an organic base with these polar solvents. As the organic base, amines are suitable, such as ethylamine, propylamine, butylamine, diethylamine, trimethylamine, triethylamine, tributylamine, diisopropyl. Ethylamine, dicyclohexylethylamine, N-methylpyrrolidine, N-methylpiperidine, dimethylaniline, diethylaniline, etc. are used.

More preferably, it is recommended to use a mixture of an organic phosphorus compound together with a polar solvent and an organic base.

Examples of the organic phosphorus compound include the phosphites and phosphines mentioned above.

The mixing amount of the organic base is about 0.05 to 5 to the polar solvent.
The amount of the organic phosphorus compound mixed is preferably about 0.01 to 1 mol/molar relative to the polar solvent.

When the organic liquid is a hydroformylation reaction liquid, the most preferable composition of the removing liquid is a combination of an ether, an organic base, and an organic phosphorus compound.

The amount of desorbed liquid is often about 3 to 15 times the amount of adsorbent packed in the column.

The temperature of the desorption operation using the desorption liquid is generally desirably higher, but in consideration of the boiling point and thermal efficiency of the desorption liquid, it is usually set at about room temperature to 50°C.

By the above desorption operation, 99.9% or more of the Group 1 noble metal complex adsorbed on the adsorbent is eluted into the desorption solution. When the solvent in the desorbed liquid extracted from the tower is distilled off,
A Group Ⅰ noble metal complex is recovered.

Since the recovered group (I) noble metal complex does not have a decrease in catalytic activity, it can be reused as it is in a reaction such as a hydroformylation reaction without any activation treatment. Also,
The activated carbon adsorbed with the Group (I) noble metal complex described above can also be used as it is as a catalyst for the next reaction.

Function: In the present invention, the first method using specially treated activated carbon is
By adsorbing the Group 1 noble metal complex and desorbing the Group 1 noble metal complex from the adsorbent using a desorption liquid, the expensive Group 1 noble metal complex can be recovered without deterioration of catalytic activity. In this way, Group I noble metal complexes can be recovered without loss.

This is thought to be based on the following reasons.

The activated carbon used in the present invention has been selected to have a specific pore distribution, and has been subjected to oxidation treatment.
The number of adsorption active sites on the surface increases, and the ability to adsorb group (I) noble metal complexes is improved. In addition, since this oxidized activated carbon is further treated with an organic phosphorus compound, the adsorption points on the surface of the activated carbon that are so active that it becomes difficult to desorb when adsorbing the Group I noble metal complex, This is controlled in advance by supporting an organic phosphorus compound.

EXAMPLES Next, the present invention will be further explained with reference to Examples. below"
"parts" and "%" are expressed on a weight basis.

Example 1 U blood bean 11 Pore volume in the range of 20 to 300 pore diameter is 0.51 m
30 g of 6% nitric acid was added to a reprinted activated carbon (Diahope manufactured by Mitsubishi Chemical Industries, Ltd.) log having a pore size distribution of 1/g, and the mixture was left at room temperature for 15 minutes, with occasional stirring. Next, the activated carbon is filtered out, thoroughly washed with water, and then heated to a temperature of 1.
Vacuum drying was performed at 20°C for 2 hours.

Next, this nitric acid-treated activated carbon was added to triphenylphosphine (
Reagent grade 1) 2.13 g (1 m-ma for activated carbon
t/g) in a tetrahydrofuran solution containing 30
It was left at room temperature for a minute, then taken out and vacuum-dried at room temperature for 2 hours.

As a result, an adsorbent for recovery of group (I) noble metal complexes was obtained.

Hydroformyl - 100 parts of oleic acid, rhodium oxide o, o in a high pressure reactor
ti, 0.5 part of triphenylphosphine was added,
Hz/CO gas at a reaction sensitivities of 120℃ and 60kg/
It was press-fitted so that the temperature was "c+s", and the reaction was carried out at 120° C. for 4 hours.

In the reaction from oleic acid to formylstearic acid, both the conversion rate and the selectivity were 99% or more, and rhodium was dissolved in the reaction solution in looILg/g.

100 g of the above hydroformylation reaction solution was added to an adsorption tower (9 tmm φ
The temperature of the reaction solution was set to 100° C. and the space velocity was set to 1hr.

Even after passing 100 g of the reaction solution, no rhodium was detected in the eluate.

1j 50 g of toluene was passed through the upper part of the adsorption tower to wash away the reaction liquid in the adsorption tower. This effluent contained no rhodium.

Next, in order to desorb the rhodium complex adsorbed on the adsorbent, a desorption solution consisting of a mixture of 80 g of tetrahydrofuran, 20 g of n-butylamine, and triphenylphosphine Ig was passed through the top of the adsorption tower. The temperature of the desorption solution was set at 35°C.

When the amount of rhodium in the effluent in this desorption operation was measured, it was found that 8% of the rhodium used in the hydroformylation reaction.
It was found that more than 9.9% was recovered.

After the solvent was distilled off under reduced pressure from the effluent after the desorption operation, the hydroformylation reaction of oleic acid was carried out under the same temperature and pressure conditions as above, using the remaining liquid as a catalyst. did.

Oleic acid was converted to formylstearic acid with both conversion rate and selectivity of 99% or more.

Example 2 The raw material activated carbon in Example 1 was aerated at 400"C for 1 hour using a rotary kiln, and further treated with triphenylphosphine in the same manner as in Example 1 to produce an adsorbent for the recovery of group (I) noble metal complexes. I got it.

Adsorption operation using this adsorbent under the same conditions as in Example 1,
Then, a desorption operation was performed.

When the amount of rhodium in the effluent from the desorption operation was measured, it was found that 99.8% or more of rhodium was recovered.

Example 3 The same experiment as in Example 1 was repeated except that triphenylphosphine was replaced with triethylphosphite. That is, the treatment of activated carbon treated with nitric acid with an organic phosphorus compound (triethylphosphite) 1. The hydroformylation reaction was carried out by charging 0.32 parts of triethyl phosphite with 0.012 parts of rhodium oxide, and 80 g of tetrahydrofuran, n
-20 g of butylamine and triethyl phosphite
0.8g of the mixture was used.

When the amount of rhodium in the effluent from the desorption operation was measured, it was found that 38.8% or more of rhodium was recovered.

Example 4 Hydridocarbonyltris(triphenylphosphine)rhodium complex (H) (Go) [P(Cz Hr)J13 Rh was used instead of rhodium oxide as the catalytic rhodium compound, and methyl oleate was used instead of oleic acid. Otherwise, the same experiment as in Example 1 was conducted. The amount of catalyst was 0.05 parts per 100 parts of methyl oleate.

In the reaction from methyl oleate to methyl formyl stearate, both conversion rate and selectivity were 99% or more.

Next, using this adsorbent, an adsorption operation and then a desorption operation were performed under the same conditions as in Example 1.

When the amount of rhodium in the effluent from the desorption operation was measured, it was found that more than 99.9% of rhodium was recovered.

Comparative Example 1 The same experiment as in Example 1 was repeated, except that the nitric acid-treated activated carbon (not treated with triphenylphosphine) in Example 1 was used as an adsorbent.

As a result, no rhodium was detected in the effluent from the adsorption operation, confirming the excellent adsorption ability of nitric acid-treated activated carbon.However, when the amount of rhodium in the effluent from the desorption operation was measured, the recovery rate of rhodium was approximately 50%, indicating poor desorption performance of the rhodium complex from the adsorbent. When only triethylphosphine was omitted from the composition of the desorbed solution, and when triethylphosphine and n-butylamine were omitted, the rhodium recovery rates were 40% and 20%, respectively, and the rhodium recovery rates further decreased.

Comparative Example 2 The same experiment as in Example 1 was repeated except that magnesium silicate having a particle size of 30 to 60 mesh was used as the adsorbent.

Measurement of the amount of rhodium in the ejected liquid during the adsorption operation revealed that about 50% of the rhodium had flowed out.

In addition, when measuring the amount of rhodium in the effluent during the desorption operation, the recovery rate of rhodium was about 40%, and the recovery rate of the catalyst used in the hydroformylation reaction was about 20% (
50X 40/100) There was.

When only triethylphosphine was omitted from the composition of the desorbed solution, and when triethylphosphine and n-butylamine were omitted, the recovery rate of rhodium further decreased.

Effects of the Invention By using the adsorbent of the present invention, it is possible to almost quantitatively remove group
It is possible to adsorb the Group No. 1 noble metal complex, and furthermore, the adsorbed Group I noble metal complex can be almost quantitatively desorbed from the adsorbent after this adsorption. Therefore, it is advantageous because the expensive Group I noble metal complex can be reused without loss.

In particular, even Group I noble metal complexes that are uniformly dissolved in high-boiling products can be recovered almost quantitatively by the adsorbent of the present invention before distillation or other processes that may cause thermal deterioration. Since it can be reused without any activation means, it has great significance in the chemical industry.

In addition, according to the method of the present invention that utilizes an adsorbent, the organic phosphorus compound added as a ligand does not mix with the target product, and the entire process can be significantly simplified compared to conventional methods.

Claims (1)

[Claims] 1. An adsorbent for recovering Group VIII noble metal complexes, which is made of activated carbon that has been previously oxidized and further supports an organic phosphorus compound. 2. The recovery adsorbent according to claim 1, wherein the activated carbon before oxidation treatment has a pore distribution with a pore diameter in the range of 20 to 300 Å and a pore volume of 0.35 ml/g or more. . 3. The recovery adsorbent according to claim 1, wherein the oxidized activated carbon is obtained by nitric acid oxidation. 4. The recovery adsorbent according to claim 1, wherein the oxidized activated carbon is obtained by oxidation with air or oxygen at high temperatures. 5. The recovery adsorbent according to claim 1, wherein the amount of the organic phosphorus compound supported on the oxidized activated carbon is 0.1 to 5 mmol/g. 6. The recovery adsorbent according to claim 1, wherein the organic phosphorus compound is a phosphite or a phosphine. 7. The recovery adsorbent according to claim 1, wherein the Group VIII noble metal is rhodium. 8. In adsorbing and separating the Group VIII noble metal complex in the organic liquid by contacting the organic liquid containing the Group VIII noble metal complex with an organic phosphorus compound as a ligand with an adsorbent,
A method for recovering a Group VIII noble metal complex, characterized in that the adsorbent is activated carbon that has been previously oxidized and further supports an organic phosphorus compound. 9. The recovery method according to claim 8, characterized in that the adsorbent is packed in a column and brought into contact with the organic liquid containing the Group VIII noble metal complex. 10. Recovery according to claim 8, characterized in that the group VIII noble metal complex adsorbed on the adsorbent is desorbed by contacting the adsorbent after adsorption treatment with a desorption liquid. Method. 11. The recovery method according to claim 8, wherein the desorption liquid has a composition consisting of a polar solvent, an organic base, and an organic phosphorus compound.