JPH0475078B2 - - Google Patents
Info
- Publication number
- JPH0475078B2 JPH0475078B2 JP10576983A JP10576983A JPH0475078B2 JP H0475078 B2 JPH0475078 B2 JP H0475078B2 JP 10576983 A JP10576983 A JP 10576983A JP 10576983 A JP10576983 A JP 10576983A JP H0475078 B2 JPH0475078 B2 JP H0475078B2
- Authority
- JP
- Japan
- Prior art keywords
- acid
- hydrofluoric acid
- pickling
- tank
- diffusion dialysis
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims description 72
- 238000005554 pickling Methods 0.000 claims description 37
- 238000009792 diffusion process Methods 0.000 claims description 35
- 238000000502 dialysis Methods 0.000 claims description 33
- 239000002699 waste material Substances 0.000 claims description 28
- 239000007788 liquid Substances 0.000 claims description 20
- 150000007522 mineralic acids Chemical class 0.000 claims description 15
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 12
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 10
- 229910017604 nitric acid Inorganic materials 0.000 claims description 10
- 239000002184 metal Substances 0.000 claims description 9
- 229910052751 metal Inorganic materials 0.000 claims description 9
- 150000002739 metals Chemical class 0.000 claims description 4
- 238000003672 processing method Methods 0.000 claims description 2
- 238000005406 washing Methods 0.000 claims description 2
- 229960002050 hydrofluoric acid Drugs 0.000 description 35
- 239000000243 solution Substances 0.000 description 20
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 15
- 239000002253 acid Substances 0.000 description 13
- 229910052742 iron Inorganic materials 0.000 description 8
- 238000011084 recovery Methods 0.000 description 6
- 239000003011 anion exchange membrane Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 239000012528 membrane Substances 0.000 description 4
- -1 stainless steel Chemical class 0.000 description 4
- 229910052500 inorganic mineral Inorganic materials 0.000 description 3
- 239000011707 mineral Substances 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 238000011282 treatment Methods 0.000 description 2
- 229910015475 FeF 2 Inorganic materials 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910021645 metal ion Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000010422 painting Methods 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/36—Regeneration of waste pickling liquors
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Description
【発明の詳細な説明】
本発明は弗酸含有酸洗廃液の処理方法に関し、
特に硝弗酸酸洗廃液より高価な弗酸を高率よく回
収する方法に関する。[Detailed Description of the Invention] The present invention relates to a method for treating hydrofluoric acid-containing pickling waste liquid,
In particular, it relates to a method for recovering more expensive hydrofluoric acid from nitric-fluoric acid pickling waste liquid at a high rate.
従来、ステンレス鋼などの金属にメツキや塗
装、その他の表面処理を施す場合、これらの処理
に先立つてスケール除去などの目的で酸洗が行な
われる。この場合、酸洗溶液は一般に硝弗酸水溶
液等の弗酸と鉱酸の混酸水溶液であり、該溶液中
の弗酸と鉱酸の割合は酸洗効果が最高となるよう
に選定される。金属の酸洗によつて生じた廃液は
なお多量の酸を含有している。したがつて、これ
を廃棄すれば、資源の損失であるばかりか公害を
発生するおそれがあるため、これらの廃液から
酸、特に高価な弗酸を回収することが望まれる。
近年、これらの廃液から酸を回収し再使用する方
法として、陰イオン交換膜を用いた拡散透析を組
合せた金属酸洗システムが提案されている。しか
しながら、上記した弗酸含有の酸洗廃液をそのま
ま拡散透析しただけでは、特に弗酸の回収率を上
げることが困難であつた。 Conventionally, when plating, painting, or other surface treatments are applied to metals such as stainless steel, pickling is performed for purposes such as scale removal prior to these treatments. In this case, the pickling solution is generally an aqueous mixed acid solution of hydrofluoric acid and mineral acid, such as an aqueous nitric-fluoric acid solution, and the ratio of hydrofluoric acid and mineral acid in the solution is selected so as to maximize the pickling effect. The waste liquid produced by pickling metals still contains large amounts of acid. Therefore, if this is disposed of, there is a risk that not only resources will be lost but also pollution will be generated, so it is desirable to recover acids, especially expensive hydrofluoric acid, from these waste liquids.
In recent years, a metal pickling system combining diffusion dialysis using an anion exchange membrane has been proposed as a method for recovering and reusing acid from these waste liquids. However, it has been particularly difficult to increase the recovery rate of hydrofluoric acid by simply subjecting the hydrofluoric acid-containing pickling waste solution to diffusion dialysis as it is.
本発明者等は上記問題を解決するために鋭意研
究した。その結果、弗酸含有の酸洗廃液に弗酸以
外の酸を添加して拡散透析することにより、該弗
酸の回収率を向上し得ることを見出し、本発明を
提供するに至つたものである。即ち、本発明は弗
酸と他の無機酸とにより金属を洗浄して得られる
酸洗廃液に、弗酸以外の無機酸を添加して拡散透
析することを特徴とする酸洗廃液の処理方法であ
る。特に本発明においては、上記した酸洗廃液の
弗酸以外の無機酸と同種の無機酸を添加し、該無
機酸の濃度を1N以上に維持して拡散透析に供す
ることが好ましい。 The inventors of the present invention have conducted extensive research to solve the above problems. As a result, they discovered that the recovery rate of hydrofluoric acid could be improved by adding an acid other than hydrofluoric acid to the hydrofluoric acid-containing pickling waste solution and performing diffusion dialysis, which led them to provide the present invention. be. That is, the present invention provides a method for treating pickling waste liquid, which is characterized in that an inorganic acid other than hydrofluoric acid is added to the pickling waste liquid obtained by washing metals with hydrofluoric acid and another inorganic acid, and the mixture is subjected to diffusion dialysis. It is. Particularly in the present invention, it is preferable to add an inorganic acid of the same type as the inorganic acid other than hydrofluoric acid in the above-mentioned pickling waste solution, maintain the concentration of the inorganic acid at 1N or more, and use it for diffusion dialysis.
本発明により酸洗廃液の特に弗酸を収率よく回
収できる作用機構については、十分に明確ではな
い。しかしながら、本発明者らは、酸洗廃液中に
溶解した鉄などの金属イオンが弗酸と錯イオン
（例えばFeF++、FeF2 +など）を形成するため、
拡散透析による該弗酸の回収率が低下するが、本
発明では無機酸の添加により上記の錯イオンから
弗酸が遊離するため拡散透析による該弗酸の回収
率が向上するものと推測している。 The mechanism by which the present invention enables recovery of hydrofluoric acid, particularly hydrofluoric acid, from pickling waste liquid in a high yield is not sufficiently clear. However, the present inventors found that because metal ions such as iron dissolved in the pickling waste liquid form complex ions (e.g. FeF ++ , FeF 2 +, etc.) with hydrofluoric acid,
Although the recovery rate of the hydrofluoric acid by diffusion dialysis decreases, in the present invention, it is assumed that the addition of an inorganic acid liberates hydrofluoric acid from the above complex ions, so that the recovery rate of the hydrofluoric acid by diffusion dialysis improves. There is.
本発明に用いられる弗酸以外の無機酸として
は、硝酸、硫酸又は塩酸等の鉱酸の水溶液で特に
硝酸が多用される。酸洗廃液中の無機酸の濃度
は、酸洗廃液中の鉄イオンの濃度及び弗酸の濃度
等により若干異なるが、一般に1N以上が好まし
い。上記した無機酸の濃度について上限は特に制
限されないが、余りに高濃度であつても本発明の
効果は特に良くならない。一般には6N程度あれ
ば十分である。 As the inorganic acid other than hydrofluoric acid used in the present invention, an aqueous solution of a mineral acid such as nitric acid, sulfuric acid or hydrochloric acid, in particular nitric acid, is frequently used. The concentration of the inorganic acid in the pickling waste solution varies slightly depending on the concentration of iron ions and hydrofluoric acid in the pickling waste solution, but is generally preferably 1N or more. There is no particular upper limit to the concentration of the above-mentioned inorganic acid, but even if the concentration is too high, the effects of the present invention will not be particularly improved. Generally, about 6N is sufficient.
本発明における拡散透析の処理は、一般に知ら
れている拡散透析装置を用い、透析膜として陰イ
オン交換膜が用いられる。 The diffusion dialysis treatment in the present invention uses a generally known diffusion dialysis apparatus, and an anion exchange membrane is used as the dialysis membrane.
以下、本発明の処理方法を用いた代表的な１例
を図面に基づき詳細に説明する。第１図は本発明
方法を用いた処理システムを示す工程図である。
酸洗槽１において、例えば0.5〜4Nの硝酸又は硫
酸等の鉱酸と0.5〜4Nの弗酸の混酸水溶液を酸洗
液とし、これに被処理金属を浸漬するか或いは上
記酸洗液のシヤワーに金属を曝露するなどの公知
の洗浄方式により処理される。酸洗槽内１の酸洗
廃液の少なくとも一部をパイプ１１を通して抜き
出し、必要により静定し、場合によつては一部を
パイプ１２によりバイパスして酸洗槽へ戻すと共
に残部を必要により凝集・濾過させた後、所定の
無機酸溶液を１３より添加した後、パイプ１４よ
り拡散透析装置２により処理する。一般に無機酸
溶液の添加は、酸洗槽から抜き出しラインのう
ち、拡散透析装置２以前であればどこでもよい。 Hereinafter, one typical example using the processing method of the present invention will be explained in detail based on the drawings. FIG. 1 is a process diagram showing a processing system using the method of the present invention.
In the pickling tank 1, a mixed acid aqueous solution of, for example, 0.5-4N nitric acid or sulfuric acid and 0.5-4N hydrofluoric acid is used as the pickling solution, and the metal to be treated is immersed in this or the pickling solution is showered. The metal is treated by known cleaning methods such as exposing the metal to. At least a part of the pickling waste liquid in the pickling tank 1 is extracted through the pipe 11, and is stabilized if necessary, and in some cases, a part is bypassed through the pipe 12 and returned to the pickling tank, and the remaining part is coagulated if necessary. - After filtration, a predetermined inorganic acid solution is added from 13, and then treated by diffusion dialysis device 2 through pipe 14. Generally, the inorganic acid solution may be added anywhere in the extraction line from the pickling tank as long as it is before the diffusion dialysis device 2.
拡散透析装置において、一方に水を15より供給
し、これに酸を回収してパイプ１６よりタンク３
に至る。他方、酸を除かれた液は１７より系外に
排出される。これは必要により金属成分の回収処
理などを行つた後、廃棄される。タンク３におい
ては、酸洗槽の状態に応じて追加の酸の添加、水
の補給あるいは他の薬剤の添加を行い、パイプ１
８より酸洗槽に再供給される。 In the diffusion dialysis device, water is supplied from 15 to one side, and acid is collected from this and sent to tank 3 from pipe 16.
leading to. On the other hand, the liquid from which the acid has been removed is discharged from the system through 17. This is disposed of after performing recovery processing for metal components as necessary. In tank 3, additional acid is added, water is replenished, or other chemicals are added depending on the condition of the pickling tank, and pipe 1
8, it is re-supplied to the pickling tank.
本発明において循環する酸洗廃液の量は、その
プロセスによつて異なるが、一般に酸洗槽内の撹
拌状態を良好にする目的、或いは槽内の酸濃度を
所定の範囲内に維持する目的、更には槽内に不可
避的に持ち込まれる不純物の濃度を一定限度以下
に維持する目的など必要とする目的に適合する量
を選定すればよい。 The amount of pickling waste liquid circulated in the present invention varies depending on the process, but generally the purpose is to improve the stirring state in the pickling tank, or to maintain the acid concentration in the tank within a predetermined range, Furthermore, the amount may be selected to suit the desired purpose, such as maintaining the concentration of impurities unavoidably brought into the tank below a certain limit.
以下、本発明を詳細に説明するために実施例を
示すが、本発明は以下の実施例に特に限定される
ものではない。 EXAMPLES Hereinafter, examples will be shown to explain the present invention in detail, but the present invention is not particularly limited to the following examples.
実施例 １
鉄24ｇ／、弗酸0.91N、硝酸0.41Nを含む硝
弗酸性廃液に、硝酸を加え4Nに調製し、その液
をフイルタープレス型拡散透析装置（徳山曹達(株)
製TSD−２型）で拡散透析を行なつた。拡散透
析槽は有効膜面積2dm2の陰イオン交換膜（商品
名ネオセプタAFN 徳山曹達(株)製）をくみこん
だ。水は20℃の水を用い、拡散透析槽の上部から
360ml／hrで拡散室に供給した。酸洗廃液は、拡
散透析槽の下部から供給した。その結果、透析槽
の下部から弗酸0.46N、鉄1.1ｇ／、硝酸2.6N
の拡散液を回収した。弗酸は酸洗廃液の63％が回
収された。Example 1 Nitric acid was added to a nitric-fluoric acid waste solution containing 24 g of iron, 0.91 N of hydrofluoric acid, and 0.41 N of nitric acid to adjust the concentration to 4 N, and the solution was transferred to a filter press diffusion dialysis device (Tokuyama Soda Co., Ltd.).
Diffusion dialysis was performed using a TSD-2 model (manufactured by TSD Corporation). The diffusion dialysis tank was equipped with an anion exchange membrane (trade name: NeoSepta AFN, manufactured by Tokuyama Soda Co., Ltd.) with an effective membrane area of 2 dm 2 . Use water at 20℃ and pour it from the top of the diffusion dialysis tank.
It was supplied to the diffusion chamber at 360 ml/hr. The pickling waste liquid was supplied from the bottom of the diffusion dialysis tank. As a result, 0.46N of hydrofluoric acid, 1.1g of iron, and 2.6N of nitric acid were found at the bottom of the dialysis tank.
The diffusion liquid was collected. 63% of hydrofluoric acid was recovered from the pickling waste liquid.
実施例 ２
鉄21ｇ／、弗酸1.38N、硫酸0.80Nを含む硝
酸酸性廃液に、硫酸を加え5Nに調製し、その液
をフイルタープレス型拡散透析装置（徳山曹達(株)
製TSD−２型）で拡散透析をおこなつた。拡散
透析槽は有効膜面積2dm2の陰イオン交換膜（商
品名ネオセプタ AFN 徳山曹達(株)製）をくみ
こんだ。水は20℃の水を用い、拡散透析槽の上部
から360ml／hrで拡散室に供給した。酸洗廃液は、
拡散透析槽の下部から供給した。その結果、透析
槽下部から鉄1.9ｇ／、弗酸0.84N、硫酸4.0の
拡散液を回収した。弗酸は酸洗廃液の61％が回収
された。Example 2 Sulfuric acid was added to a nitric acid waste solution containing 21 g of iron, 1.38 N of hydrofluoric acid, and 0.80 N of sulfuric acid to adjust the concentration to 5 N, and the solution was heated using a filter press diffusion dialysis device (Tokuyama Soda Co., Ltd.).
Diffusion dialysis was performed using a TSD-2 model (manufactured by TSD Corporation). The diffusion dialysis tank contained an anion exchange membrane (trade name: Neocepta AFN, manufactured by Tokuyama Soda Co., Ltd.) with an effective membrane area of 2 dm 2 . Water at 20°C was supplied to the diffusion chamber from the top of the diffusion dialysis tank at a rate of 360 ml/hr. The pickling waste liquid is
It was supplied from the bottom of the diffusion dialysis tank. As a result, a diffusion solution containing 1.9 g of iron, 0.84 N of hydrofluoric acid, and 4.0 N of sulfuric acid was recovered from the bottom of the dialysis tank. As for hydrofluoric acid, 61% of the pickling waste was recovered.
比較例 １
鉄24ｇ／、弗酸0.91N、硝酸0.41Nを含む硝
弗酸酸性廃液を、フイルタープレス型拡散透析装
置（徳山曹達(株)製TSD−２型）で拡散透析をお
こなつた。拡散透析槽は有効膜面積2dm2の陰イ
オン交換膜（商品名ネオセプタAFN 徳山曹達
(株)製）をくみこんだ。水は20℃の水を用い、拡散
透析槽の上部から360ml／hrで拡散室に供給した。
酸洗廃液は、拡散透析槽の下部から供給した。そ
の結果、透析槽下部から弗酸0.41N、鉄1.6ｇ／
、硝酸0.38Nの拡散液を回収した。弗酸は酸洗
廃液の49％が回収された。Comparative Example 1 A nitric-fluoric acid acidic waste solution containing 24 g of iron, 0.91 N of hydrofluoric acid, and 0.41 N of nitric acid was subjected to diffusion dialysis using a filter press type diffusion dialysis device (Model TSD-2 manufactured by Tokuyama Soda Co., Ltd.). The diffusion dialysis tank is an anion exchange membrane with an effective membrane area of 2 dm2 (product name Neocepta AFN Tokuyama Soda).
Co., Ltd.). Water at 20°C was supplied to the diffusion chamber from the top of the diffusion dialysis tank at a rate of 360 ml/hr.
The pickling waste liquid was supplied from the bottom of the diffusion dialysis tank. As a result, 0.41N of hydrofluoric acid and 1.6g of iron were collected from the bottom of the dialysis tank.
, a 0.38N nitric acid diffusion solution was collected. 49% of hydrofluoric acid was recovered from the pickling waste liquid.
第１図は本発明方法を用いた処理システムを示
す工程図である。図中１は酸洗槽、２は拡散透析
装置、３はタンクである。
FIG. 1 is a process diagram showing a processing system using the method of the present invention. In the figure, 1 is a pickling tank, 2 is a diffusion dialysis device, and 3 is a tank.
Claims (1)
られる酸洗廃液中に、弗酸以外の無機酸を添加し
て拡散透析することを特徴とする弗酸を含む酸洗
廃液の処理方法。 ２ 酸洗廃液中の弗酸以外の無機酸の濃度が1N
以上である特許請求の範囲第１項記載の方法。 ３ 弗酸以外の無機酸の硝酸又は硫酸である特許
請求の範囲第１項記載の方法。[Claims] 1. Hydrofluoric acid, which is characterized in that an inorganic acid other than hydrofluoric acid is added to a pickling waste solution obtained by washing metals with hydrofluoric acid and another inorganic acid, and then subjected to diffusion dialysis. Processing method for pickling waste liquid containing 2 The concentration of inorganic acids other than hydrofluoric acid in the pickling waste liquid is 1N.
The method according to claim 1, which is the above. 3. The method according to claim 1, wherein the inorganic acid other than hydrofluoric acid is nitric acid or sulfuric acid.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10576983A JPS59230691A (en) | 1983-06-15 | 1983-06-15 | Treatment of fluoric acid-containing waste pickling liquid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10576983A JPS59230691A (en) | 1983-06-15 | 1983-06-15 | Treatment of fluoric acid-containing waste pickling liquid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59230691A JPS59230691A (en) | 1984-12-25 |
| JPH0475078B2 true JPH0475078B2 (en) | 1992-11-27 |
Family
ID=14416375
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10576983A Granted JPS59230691A (en) | 1983-06-15 | 1983-06-15 | Treatment of fluoric acid-containing waste pickling liquid |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59230691A (en) |
-
1983
- 1983-06-15 JP JP10576983A patent/JPS59230691A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59230691A (en) | 1984-12-25 |
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