JPS6354991A - Method for removing lead - Google Patents

Abstract

PURPOSE:To efficiently adsorb and remove lead in a lead-contg. soln. by bringing the soln. into contact with a chelate resin having a functional group contg. a phosphorous atom or pyridine group. CONSTITUTION:The lead-contg. soln. is brought into contact with the chelate resin having the functional group contg. the phosphorus atom (e.g., phosphine group) or pyridine group. As a result, the lead can be selectively adsorbed and removed from the soln. contg. Co, Ni, copper, etc. The adsorption is preferably executed at 0.5-10pH of the lead-contg. soln. in order to prevent the deterioration in adsorptivity of the lead on the chelate resin. The rare metals adsorbed by the chelate resin can be eluted and recovered by using a hydrochloric acid, nitric acid, etc. The chelate resin subjected to the desorption of the lead is repeatedly usable as an adsorptive capturing agent for the lead after the resin is treated by an aq. sodium hydroxide soln., etc.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for removing lead from a lead-containing solution.

More specifically, the present invention relates to a method for efficiently adsorbing and removing lead in a solution using a special chelate resin.

(Prior art) Many heavy metal trapping agents and trapping methods have been proposed so far.
However, the adsorption treatment method using a chelate resin has an extremely low lower limit concentration after treatment, and various proposals have been made as a preferable method.

A method for removing lead contained in an aqueous solution using an ion exchange resin or chelate resin is a method in which lead is adsorbed using a chelate resin with polyaminopolythioic acid as a ligand (Japanese Patent Laid-Open No. 55-8
4309), a method of adsorption with a chelate resin containing polyaminopolycarboxylic acid as a ligand (Japanese Unexamined Patent Publication No. 55-84
310), a method of adsorption with a chelating agent having a mercapto group as a ligand (JP-A-48-79185 Ig
) is publicly known.

<Problems to be solved by the invention> The present invention proposes a new chelate resin for adsorbing lead. In this case, known chelate resins are susceptible to the effects of coexisting ions present in the solution, and therefore have disadvantages such as a marked decrease in the amount of adsorbed fF of lead and a high equilibrium concentration of lead adsorption.

In view of these circumstances, the present inventors conducted intensive research to find a method for removing lead that is less susceptible to the influence of coexisting ions and can lower the equilibrium adsorption concentration, and as a result, the present invention was completed.

<Means for solving the problem> That is, the present invention provides a method for removing lead contained in a solution, which is characterized by bringing a lead-containing solution into contact with a chelate resin having a functional group containing a phosphorus atom or a pyridine group. It is.

The chelate resin used in the present invention is a chelate resin having a phosphorus atom-containing functional group or a pyridine group in its molecule, and if the resin has such a functional group, a resin base,
There are no particular limitations on the shape or manufacturing method.

Examples of the functional group containing a phosphorus atom include a phosphine group, a phosphonium base, a phosphinic acid group, a phosphinic acid ester group, a phosphonic acid group, a phosphonic acid ester group, an aminoalkylenephosphonic acid group, and an aminoalkylenephosphonic acid ester group. .

Examples of such chelate resins include the following.

(1) Polymers such as styrene-divinylbenzene copolymers, phenol resins, polyethylene, and polypropylene containing halogenated alkyl groups such as chloromethyl groups and bromomethyl groups, or halogen atoms such as bromine and iodine, as well as lithium diphenylphosphine and sodium diphenyl. A chelate resin having a phosphine group or a phosphonium base obtained by reacting a phosphine compound such as phosphine, lithium phenylphosphine, or tricresylphosphine, or a mixture thereof.

(2) Styrene-divinylbenzene copolymers, phenol resins, aniline resins, m-phenylene polymers containing halogenated alkyl groups such as chloromethyl groups and bromomethyl groups (hereinafter referred to as resins having halogenated alkyl groups) and phosphorous acid derivatives such as triethyl phosphite, triphenyl phosphite, and trimethyl phosphite, or mixtures thereof (hereinafter referred to as phosphorous acid derivatives).
A chelate resin having a phosphonic acid ester group obtained by reacting.

(3) A chelate resin having a phosphonic acid group obtained by hydrolyzing the chelate resin having a phosphonic acid ester group or the chelate resin having a phosphonium base.

(4) A chelate resin having a phosphinic acid group obtained by reacting a styrene-divinylbenzene copolymer, polystyrene, etc. with trichloride and then hydrolyzing it.

(5) A chelate resin containing a phosphinic acid ester group obtained by reacting a resin containing an amino group with a chloromethylphosphinic acid ester.

(6) Resins having primary or secondary amine groups containing halogenated alkyl phosphates such as diethyl chloromethylphosphonate, ethyl chloromethylphosphonate, diphenyl chloromethylphosphonate, dicresyl chloromethylphosphonate, ethyl chloromethylphosphinate, or these esters. A chelate resin containing an aminoalkylene phosphate group obtained by reacting a mixture.

(7) Hydrolyzing the chelate resin having an aminoalkylene phosphate group or reacting in exactly the same manner except that the phosphorous acid derivative used in the production of the aminoalkylene phosphate group-containing resin is changed to phosphorous acid. A chelate resin containing an aminoalkylene phosphate group obtained by

(8) A chelate resin containing an alkali metal such as sodium, potassium, calcium, or alkaline earth metal salt of the above-mentioned acid.

In particular, a chelate resin having a phosphorus compound-based functional group is preferably used because it forms a strong chelate bond with lead via an amino group.

Examples of the chelate resin having a pyridine group include the following.

(1) Polymers of monomers such as 4-vinylpyridine and 2-vinylpyridine, or copolymers of these monomers and other monomers that can be copolymerized.

(2) Styrene-divinylbenzene copolymers, phenol resins, polyethylene resins, polypropylene resins, etc. containing halogenated alkyl groups such as chloromethyl groups and bromomethyl groups, halogen atoms such as bromine and iodine, epoxy groups, and isocyanate groups. polymer, acrylonitrile,
A copolymer of vinyl cyanide monomers such as α-chloroacrylonitrile and methacrylonitrile with other ethylenically unsaturated monomers that can be copolymerized with 2-aminopyridine,
4-aminopyridine, 2-amino-3-picoline, 2-
A chelate resin obtained by reacting amino-4-picoline, 2-amino-4,6-dimethylpyridine, 2-(aminomethyl)pyridine, 3-(aminoethyl)pyridine, etc.

(3) Polymers having primary or secondary amino groups, such as styrene-divinylbenzene copolymers, phenol resins, and polyethylene resins, include 2-chloropyridine, 3-chloropyridine, 2-bromopyridine, 3-bromo pyridine,
Chelate resin obtained by reacting 2-amino-5-bromopyridine, 2-bromo-5-methylpyridine, etc.

In the present invention, a chelate resin having such a specific functional group is brought into contact with a lead-containing solution. Examples of the lead-containing solution include mine wastewater, zinc smelting factory wastewater, etc.
Effective against lead-containing solutions such as mineral acid leachate from catalyst scrap.

Furthermore, the present invention can selectively adsorb and remove lead from a solution containing lead, such as a rare metal.

When adsorbing and removing lead from solutions containing rare metals, etc., the selective adsorption of lead varies depending on the type of chelate resin, the type of coexisting metals, pH, etc., and this can be determined by conducting preliminary experiments as appropriate. .

Rare metals are not particularly limited as long as they are not adsorbed or are difficult to adsorb to chelate resins having a functional group containing a phosphorus atom or a pyridine group, but generally include cobalt, nickel, copper, gallium, indium, Examples include aluminum, germanium, manganese, and the like.

When performing contact treatment between a lead-containing solution and a chelate resin,
In order to prevent a decrease in adsorption of lead to the chelate resin, the pH of the lead-containing solution is preferably 0.5 to 10.

The method of contacting the lead-containing solution with the chelate resin is not particularly limited; for example, a method of passing the lead-containing solution into a tower filled with the chelate resin, or a method of introducing the chelate resin into the lead-containing solution is possible. A method such as immersion and then 5-filtration separation is adopted.

The contact temperature between the lead-containing solution and the chelate resin is also not particularly limited, and is usually carried out at 0-100°C.

The contact time is also not particularly limited.

The rare metals adsorbed by the chelate resin of the present invention can be eluted and recovered using a suitable eluent. As the eluent, an acidic aqueous solution such as hydrochloric acid, nitric acid, or phosphoric acid is used.

After lead has been desorbed in this way, the chelate resin can be used as is or, if necessary, treated with water and/or a basic aqueous solution such as sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, or ammonia. After that, it can be used repeatedly as a lead adsorption collector.

<Effects of the Invention> As detailed above, the method for recovering lead from a lead-containing solution using the chelate resin having the specific functional group of the present invention has the following effects:
The adsorption capacity of the chelate resin for lead can be increased and the adsorption equilibrium concentration can be significantly lowered, and its industrial value is great.

<Examples> Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited by the following Examples unless the gist thereof is exceeded.

Example 1 0.5 g of a resin containing a phosphonate group (hereinafter, this polymer is referred to as chelate resin A) obtained by reacting 200 parts by weight of chloromethylated polystyrene with 500 parts by weight of triethyl phosphite in a toluene solvent. , lead concentration 105m
After adding 5 Qml of a pH 4 aqueous solution of g/f and performing shaking and contact treatment for 3 hours, the lead content of the treated solution was analyzed and found to be 2.3 mg/l, and the adsorbed amount of lead was 10.3 mg/l.
g resin.

Examples 2-12 Chelate resin B; Commercially available resin with phosphonic acid groups.

[DEOLITE @ ES-63 (manufactured by Diamond Sham Lofta)] Chelate resin C: Aminated polyacrylonitrile obtained by reacting 60 parts by weight of polyacrylonitrile with 103 parts by weight of diethylenetriamine in an aqueous solvent, and further in the presence of 36% hydrochloric acid. , a resin having an aminoalkylene phosphate group obtained by reacting 281 parts by weight of an aqueous formalin solution with 498 parts by weight of triethyl phosphite.

Chelate resin D: A resin having a quaternary phosphonium base obtained by reacting 200 parts by weight of chloromethylated polystyrene and 200 parts by weight of tributylphosphine in a dimethylformamide solvent.

Chelate resin E: A resin containing a quaternary phosphonium base obtained by reacting 200 parts by weight of chloromethylated polystyrene and 260 parts by weight of triphenylphosphine in a dimethylformamide solvent.

Chelate resin F: Lithium polystyrene was obtained by reacting 150 parts by weight of brominated polystyrene with 64 parts by weight of a 1.6 mol% n-butyllithium-hexane solution in a tetrahydrofuran medium.

A resin having a phosphine group was obtained by reacting this with 300 parts by weight of chlordiphenylphosphine in a tetrahydrofuran solvent and further oxidizing with 371 parts by weight of 40% peracetic acid in a methylene chloride solvent.

Chelate resin G: A resin containing a sodium salt of phosphonic acid obtained by hydrolyzing a chelate resin in a 20% aqueous solution of caustic soda.

Chelate Resin H: A resin having phosphinic acid groups obtained by reacting 100 parts by weight of polystyrene with 150 parts by weight of trichloride in a chloroform solvent, followed by hydrolysis reaction.

Chelate resin I; 100 parts by weight of aminated polystyrene in 1,2-dichloroethane solvent, cresyl chloromethylphosphinate 12
A resin having a phosphinate group obtained by reacting with 0 parts by weight.

Sumikylate MC-95 (manufactured by Sumitomo Chemical Co., Ltd.) A resin having an aminomethylene phosphonic acid group as a chelate resin.

For the chelate resin: A bead-shaped resin containing a pyridine ring obtained by polymerizing 105 g of 4-vinylpyridine and 60 g of divinylbenzene with a purity of 55%.

Chelate resin L: Sumikylate ■CR-2 (Sumitomo Chemical Co., Ltd.) A resin containing a pyridine ring.

Each of the above chelate resins was subjected to a contact shaking treatment in the same manner as in Example 1, and the treated solution was analyzed for lead, and the results shown in Table 1 were obtained.

Table 1 Example 13 20 ml of chelate resin J was packed into a column with an inner diameter of 12 mmφ, and the pH was 6, containing 97 mg/1 lead from the top of the column.
1000mj of aqueous solution! When the liquid was passed for 2 hours and the lead in the effluent was analyzed, the lead concentration was O.1 mg/j!
Met.

Example 14, Comparative Examples 1 to 3 Chelate resin J, commercially available sumichelate MC-30 having 1 group of iminonicider rJ, sumichelate 9MC-10 having polyethylene polyamino group, and sumichelate QIOR having dithiocarbamate group (manufactured by Kagakusha), 0.5g each, and 103mg/j of lead! ,knee/
Kel 115 mg/l, Cobalt 9”Img
50ml of pH 1.3 aqueous solution containing /l! In addition, after shaking and contact treatment for 3 hours, the metal concentration of the treated solution was measured, and the results shown in Table 2 were obtained.

Table 2 Example 15, Comparative Example 4.5 Instead of the aqueous solution used in Example 14, lead 8
9 mg/1, gallium 96 mg/1
, pH 1,147) containing 103 mg/l of aluminum and a contact treatment using different types of chelate resins.The metal concentration of the treatment solution was measured, and the results shown in Table 3 were obtained.

Table 3

Claims (4)

[Claims] (1) A method for removing lead, which comprises bringing a lead-containing solution into contact with a chelate resin having a functional group containing a phosphorus atom or a pyridine group. (2) The functional group containing a phosphorus atom is a phosphine group, a phosphonium base, a phosphinic acid group, a phosphinic acid ester group, a phosphonic acid group, a phosphonic acid ester group, an aminoalkylenephosphonic acid group, an aminoalkylenephosphonic acid ester group, and their The method for removing lead according to claim 1, wherein the method is a metal salt of an acid. (3) The method for removing lead according to claim 1 or 2, wherein the functional group containing a phosphorus atom is bonded to the polymer main chain via an amino group. (4) The method for removing lead according to claim 1, which comprises selectively adsorbing and removing lead from a solution containing lead and rare metals.