JPH08199366A - Treatment of waste electroless nickel plating solution - Google Patents
Treatment of waste electroless nickel plating solutionInfo
- Publication number
- JPH08199366A JPH08199366A JP5341081A JP34108193A JPH08199366A JP H08199366 A JPH08199366 A JP H08199366A JP 5341081 A JP5341081 A JP 5341081A JP 34108193 A JP34108193 A JP 34108193A JP H08199366 A JPH08199366 A JP H08199366A
- Authority
- JP
- Japan
- Prior art keywords
- soln
- nickel
- waste
- iron
- complexing agent
- 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.)
- Pending
Links
Abstract
Description
【０００１】[0001]
【産業上の利用分野】この発明は無電解ニツケル鍍金処
理の工程に於いて生成する、ニツケルイオン次亜燐酸イ
オン、有機錯化剤を含有する、化学ニツケル鍍金廃液の
無害化処理法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detoxifying a chemical nickel plating waste liquid containing nickel ion hypophosphite ion and an organic complexing agent, which are produced in the process of electroless nickel plating treatment. is there.
【０００２】[0002]
【従来の技述】化学メツキ液中に、金属、プラスチツ
ク、ガラス、等を浸漬してメツキする方法で、外部電源
を用いず、メツキが行えるのが無電解メツキと呼ばれ
る。化学ニツケルメツキは硬く緻密な厚い膜で。しか
も、均一に析出させる特徴がある。製造工程よりニツケ
ルイオン、次亜燐酸イオン、有機錯化剤を含有する、無
電解ニ、ツケルメツキ廃液が発生する、これお無害化す
る必要がある、無害化の処理方法としては電解酸化法等
が公知である。電解酸法は電解槽でニツケルイオン、次
亜．イオン、有機錯化剤を含有する廃液の電解酸化を行
い、有機錯化剤を、アルデヒド、一酸化炭素等酸化中間
体を経て、最終的には二酸化炭素に酸化してＣＯＤ成
分を減少させ、最終的にはニツケルイオンを陰極上に析
出させて無害化するのであるが、この廃液は前もつて、
金属錯塩と有機錯化剤とが分離処理が不可能な為、混合
状態のままにて電解酸化する為、電解処理時間が１２０
時間と長く、現実的処理方法に対して、連続的に排水処
理を行う場合は不適当である。2. Description of the Related Art A method of immersing metal, plastic, glass, etc. in a chemical plating solution to perform plating is called electroless plating, which can perform plating without using an external power source. Chemical nickel powder is a hard, dense and thick film. Moreover, it has a characteristic that it is uniformly deposited. Nickel ion, hypophosphite ion, containing organic complexing agent from the manufacturing process, electroless D, luciferous effluent is generated, it is necessary to detoxify, electrolytic oxidation method etc. as a detoxification treatment method It is known. The electrolytic acid method uses nickel ions in the electrolytic cell, hypoxia. Electrolytic oxidation of the waste liquid containing ions and organic complexing agent is carried out, and the organic complexing agent is finally oxidized into carbon dioxide through an aldehyde, an intermediate such as carbon monoxide, and finally COD formation.
The amount is reduced, and nickel ions are finally deposited on the cathode to make it harmless, but this waste liquid is
Since the metal complex salt and the organic complexing agent cannot be separated from each other, they are electrolytically oxidized in the mixed state.
It takes a long time, and it is not suitable for continuous treatment of wastewater, which is a practical treatment method.
【０００３】[0003]
【発明が解決しようとする課題】本発明はエネルギー消
費が少なく、処理時間が短く、金属イオンの除去効率が
優れている。ニツケルイオン、リンイオン、有機錯化剤
を含有する、無電解ニツケル廃液の処理方法を提供する
ことを目的とする。The present invention consumes less energy, has a shorter processing time, and has excellent metal ion removal efficiency. An object of the present invention is to provide a method for treating an electroless nickel waste liquid containing nickel ions, phosphorus ions and an organic complexing agent.
【０００４】[0004]
【課題を解決するための手段】本発明はニツケルイオ
ン、次亜燐酸イオン、有機錯化剤を含有する無電解ニツ
ケル廃液に塩酸を混合してＰＨを一定範囲に調整し、還
元鉄に一定時間接触させた直後、カセイソーダを添加し
て中和し、水酸化ニツケルを生成させる。ニツケルと錯
塩化しているリン酸イオンは鉄イオンに置換反応して、
リン酸鉄となり、水酸化ニツケルと共に凝集分離するこ
とよりなる。塩酸は３６％の形態で廃液に添加する、塩
酸は濃度が１５〜３６重量％として添加するのが良い、
添加量は廃液１００重量部に対し上記溶液を１〜１・５
重量部、好ましくは１〜１・２重量部とする。還元鉄は
金属球３ｍ／ｍ〜４・５ｍ／ｍの形状に焼結造粒化した
形状の球を塔状の容器に充填する。塩酸によりＰＨを一
定に調整された廃液がポンプによつて塔中を上向流して
いる間に還元鉄と接触反応して溶出する。その溶出量は
２・０００ＰＰｍ〜３・０００ＰＰｍ溶出するのが好ま
しい。混合した溶液にカセイソーダで中和する、中和点
は厳密にコントロールすることが望ましく、ＰＨ−１３
を維持するようにする。中和温度は常温でよい。この様
にして中和すると、ニツケルイオンは水酸化ニツケル、
鉄イオンはリンイオンと吸着重合して、リン酸鉄という
不溶性物質に成り、水酸化ニツケルとフロツク状に成長
し包含された状態になる。中和後の反応時間として３０
分又はそれ以上を与えることが好ましい。その後、濾過
処理を行えばリン酸鉄、水酸化ニツケルのフロツクと共
に有機錯化剤を含む溶液中から重金属類は分離出来る。
以上のように重金属類を分離した液体に硫酸を注入して
ＰＨ−１に調整する、次に直流電気分解を行う、電圧及
び電流は、１５Ｖ２・５Ａ／ｄｍ２で陽極にカーボン電
極、陰極にはＳＵＳ−２７電解して６時間、直流電気分
解を行うと、３０・０００ＰＰｍ／ＬのＣＯＤ物質（有
機錯化剤）はアルデヒド、一酸化炭素の中間体を経て最
終的には二酸化炭素に酸化してＣＯＤ成分を３０ＰＰｍ
以下まで減少させることが可能うと成る。前処理として
重金属を除外した液であるため、電気分解によるＣＯＤ
の分解時間は６時間と短縮するので現実的にも経済的に
も利用価値がある優れた方法である。According to the present invention, hydrochloric acid is mixed with an electroless nickel waste liquid containing nickel ions, hypophosphite ions and an organic complexing agent to adjust pH to a certain range, and reduced iron for a certain time. Immediately after the contact, caustic soda is added for neutralization to form nickel hydroxide. Phosphate ion complexed with nickel is replaced by iron ion,
It becomes iron phosphate and is coagulated and separated together with nickel hydroxide. Hydrochloric acid is added to the waste liquid in the form of 36%, hydrochloric acid is preferably added at a concentration of 15 to 36% by weight,
Addition amount is 1 to 1.5 for 100 parts by weight of waste liquid.
Parts by weight, preferably 1 to 1.2 parts by weight. The reduced iron is filled in a tower-shaped container with spheres having a shape in which the metal spheres are sintered and granulated into a shape of 3 m / m to 4.5 m / m. While the pH of the waste liquid is adjusted to be constant with hydrochloric acid, the waste liquid is eluted by catalytic reaction with reduced iron while flowing upward in the tower by a pump. The elution amount is preferably 2,000 PPm to 3,000 PPm. Neutralize the mixed solution with caustic soda. It is desirable to strictly control the neutralization point.
Try to maintain. The neutralization temperature may be room temperature. When neutralized in this way, the nickel ions are nickel hydroxide,
Iron ions are adsorbed and polymerized with phosphorus ions to form an insoluble substance called iron phosphate, which grows in the form of nickel hydroxide and blocks and becomes contained. 30 as the reaction time after neutralization
It is preferred to give minutes or more. After that, if a filtration treatment is performed, heavy metals can be separated from the solution containing the organic complexing agent together with the block of iron phosphate and nickel hydroxide.
Sulfuric acid is injected into the liquid from which heavy metals have been separated as described above to adjust to PH-1, and then direct current electrolysis is performed. The voltage and current are 15 V 2.5 A / dm 2 and the anode is a carbon electrode and the cathode is a cathode. Is electrolyzed by SUS-27 for 6 hours and subjected to direct current electrolysis for 6 hours, the COD substance (organic complexing agent) of 30,000 PPm / L is oxidized to carbon dioxide through an intermediate of aldehyde and carbon monoxide. And COD component is 30PPm
It will be possible to reduce to below. COD by electrolysis because it is a liquid that excludes heavy metals as pretreatment
Since the decomposition time of is shortened to 6 hours, it is an excellent method that is practically and economically useful.
【０００５】[0005]
【作用】ニツケルイオン、燐酸イオン、有機錯化剤を含
有する、無電解ニツケル廃液を単にカセイソーダで中和
するだけではニツケル成分や燐酸成分は、この錯塩化溶
液から析出分離出来ない、又、還元鉄イオンのみの存在
下に廃液をカセイソーダで中和しても、ニツケル成分及
びリン成分を効果的に分離することは出来ない。しか
し、塩酸によりＰＨ−１〜１・５に調整し、還元鉄イオ
ンを２０００ＰＰｍ〜３０００ＰＰｍ／Ｌ混合した溶液
にカセイソーダを添加しＰＨ−１３を維持するように添
加すると、下記実施例に示す如く、ニツケル成分とリン
酸成分を殆ど完全に、廃液中から除去することができ
る。以上のように重金属を分離した液体には錯化剤が残
留していてＣＯＤ成分の濃度が高く、安全放流出来ない
場合には、液中から回収又は除外処理を行わなければな
らない。これ等の溶液は活性汚泥処理としては分解効率
が悪く、二酸化炭素や窒素ガスに分解するに至るには相
当な時間を必要とするし、生物分解を行うにしても、菌
類に対して抵抗性を有うする困難な物質である。この溶
液を硫酸でＰＨ−１に調整して直流電気分解を行う、電
圧、電流は１５Ｖ ２・５Ａ／ｄｍ２で６時間バツチ式
で、３００００ＰＰｍ／ＬのＣＯＤ物質はアルデヒド、
一酸化炭素の酸化中間体を経て最終的には二酸化炭素に
酸化してＣＯＤ成分を３０ＰＰｍ／Ｌまで減少させるこ
とが可能である。重金属を除外した溶液の電気分解処理
の時間は６時間と短く経済的に使用できる方法である。[Function] Nickel components and phosphoric acid components cannot be precipitated and separated from this complex chloride solution by simply neutralizing the electroless nickel waste liquid containing nickel ions, phosphate ions and organic complexing agent with caustic soda Even if the waste liquid is neutralized with caustic soda in the presence of only iron ions, the nickel component and the phosphorus component cannot be effectively separated. However, when the pH was adjusted to PH-1 to 1.5 with hydrochloric acid, caustic soda was added to the solution in which reduced iron ions were mixed at 2000 PPm to 3000 PPm / L to maintain PH-13, as shown in the following examples. The nickel component and the phosphoric acid component can be almost completely removed from the waste liquid. As described above, if the complexing agent remains in the liquid from which the heavy metals have been separated and the concentration of COD components is high and it is not possible to safely discharge it, it is necessary to recover or exclude it from the liquid. These solutions have low decomposition efficiency for activated sludge treatment, and it takes a considerable time to decompose into carbon dioxide and nitrogen gas, and even if they are biodegraded, they are resistant to fungi. It is a difficult substance. This solution is adjusted to PH-1 with sulfuric acid and subjected to direct current electrolysis. The voltage and current are 15 V 2.5 A / dm 2 in a batch type for 6 hours. The COD substance of 30,000 PPm / L is an aldehyde,
It is possible to reduce the COD component to 30 PPm / L by finally oxidizing it to carbon dioxide through an oxidation intermediate of carbon monoxide. The time for electrolysis of the solution excluding heavy metals is as short as 6 hours, which is an economically usable method.
【０００６】[0006]
【実施例１】無電解ニツケルメツキ工程から排出された
溶液中に含んでいるニツケル金属は５０００ＰＰｍ，次
亜リン酸１００００ＰＰｍ，有機錯化剤３００００ＰＰ
ｍ、ＰＨ−４の無電解ニツケルメツキ廃液１００重量部
に塩酸１重量部を混合しＰＨ−１に調整し造粒還元鉄の
充填した塔にポンプにて塔下部より注入し上向流させ、
ＳＶ−７０にて一定量の還元鉄を溶出し混合させる。常
温にて、攪拌しつつ、濃度２０重量％のカセイソーダ水
溶液を添加してＰＨ−１３とする、３０分軽過後、固形
分を濾過し、廃液中のニツケルを測定したところ０・５
ＰＰｍであり、又リンを測定したところ０・８ＰＰｍで
あつた。Example 1 The nickel metal contained in the solution discharged from the electroless nickel plating process is 5000 PPm, hypophosphorous acid 10000 PPm, and organic complexing agent 30000 PPm.
m, 1 part by weight of hydrochloric acid was mixed with 100 parts by weight of the electroless nickel smelt waste solution of PH-4, adjusted to PH-1, and injected into the tower filled with granulated reduced iron from the lower part of the tower with an upward flow,
A certain amount of reduced iron is eluted with SV-70 and mixed. At room temperature, with stirring, a caustic soda aqueous solution having a concentration of 20% by weight was added to obtain PH-13. After 30 minutes of lightening, the solid content was filtered and the nickel in the waste liquid was measured to be 0.5.
It was PPm, and when phosphorus was measured, it was 0.8 PPm.
【０００７】[0007]
【実施例２】無電解ニツケルメツキ工程から排出された
含んでいるニツケル６０００ＰＰｍ次亜燐酸９０００Ｐ
Ｐｍ，有機錯化剤３５０００ＰＰｍＰＨ−６の無電解ニ
ツケル廃液１００重量部に塩酸１・２重量部を混合しＰ
Ｈ−１・５に調整し造粒還元鉄の充填した塔にポンプに
て塔下部から注入し上向流させ、ＳＶ−８０にて一定量
の還元鉄を溶出し混合させ、常温にて攪拌しつつ、濃度
２０重量％のカセイソーダ水溶液を添加してＰＨ−１３
とした、３０分経過後固形分を濾過した、廃液中のニツ
ケルを測定したところ０・７ＰＰｍであり、又リンを測
定したところ０・９ＰＰｍであつた。[Example 2] Nickel contained 6000PPm hypophosphorous acid 9000P discharged from the electroless nickel plating process
Pm, organic complexing agent 35000PPmPH-6 100 parts by weight of the electroless nickel waste liquid is mixed with 1.2 parts by weight of hydrochloric acid, and P
It is adjusted to H-1.5 and granulated into a column filled with reduced iron from the bottom of the column by a pump and allowed to flow upward, and a certain amount of reduced iron is eluted and mixed with SV-80 and stirred at room temperature. While adding caustic soda aqueous solution with a concentration of 20% by weight, PH-13
After the lapse of 30 minutes, the solid content was filtered, and the nickel in the waste liquid was measured to be 0.7 PPm, and the phosphorus was measured to be 0.9 PPm.
【０００８】[0008]
【実施例３】無電解ニツケルメツキ工程から排出された
廃液中からニツケルイオン、及びリン酸イオンを化学的
に除外しした廃液中に有機錯化剤（１例クエン酸ナトリ
ウム）が溶解している、この溶液を硫酸でＰＨ−１に調
整し溶液を攪拌しながら直流電気分解を行う。電圧電流
は１５Ｖ、２・５Ａ／ｄｍ２で６時間バツチ式にて電気
分解を行うとＣＯＤ３００００ＰＰｍの濃度は６時間の
分解で３０ＰＰｍ以下であつた。Example 3 An organic complexing agent (one example sodium citrate) is dissolved in a waste liquid obtained by chemically removing nickel ions and phosphate ions from the waste liquid discharged from the electroless nickel plating process. This solution is adjusted to PH-1 with sulfuric acid, and DC electrolysis is performed while stirring the solution. When the voltage and current were 15 V and 2.5 A / dm 2 and electrolysis was carried out by the batch method for 6 hours, the concentration of COD 30000 PPm was 30 PPm or less after 6 hours of decomposition.
【０００９】[0009]
【比較例１】実施例１で用いたのと同じ廃液１００重量
部をＰＨ−１にして温度を常温にて攪拌しつつ、造粒還
元鉄を充填した還元塔にポンプにてＳＶ−６０で上向流
させた液を攪拌しながら、濃度１５％カセイソーダ水溶
液を添加してＰＨ−１３とした。３０分経過後固形分を
濾過し排水中のニツケルを測定した所ろ、０、６ＰＰｍ
であり、リンを測定した所ろ０・７ＰＰｍであつた。Comparative Example 1 100 parts by weight of the same waste liquid as used in Example 1 was brought to PH-1 and stirred at room temperature while stirring, and a reducing tower filled with granulated reduced iron was pumped at SV-60. PH-13 was prepared by adding an aqueous solution of caustic soda with a concentration of 15% while stirring the liquid which was allowed to flow upward. After 30 minutes, the solid content was filtered, and the nickel in the waste water was measured.
When phosphorus was measured, it was 0.7 PPm.
【０００１０】[00010]
【比較例２】実施例１で用いたのと同じ廃液１００重量
部に塩酸１・６重量％を混合しＰＨ−１・８に調整し温
度は常温にて攪拌して造粒還元鉄充填塔にＳＶ−５０に
てポンプ注入して上向流させ、排出した溶液を攪拌しな
がら濃度２０％のカセイソーダ水溶液を添加してＰＨ−
１３とした、３０分経過後固形分を濾過し排水中のニツ
ケルを測定した所ろ０・９ＰＰｍであり、リンを測定し
た所ろ１ＰＰｍであつた。、[Comparative Example 2] 100 parts by weight of the same waste liquid as used in Example 1 was mixed with 1.6% by weight of hydrochloric acid to adjust to PH-1.8, and the temperature was agitated at room temperature to a granulated reduced iron packed tower. The solution was pumped up with SV-50 to make it flow upward, and while stirring the discharged solution, a caustic soda aqueous solution having a concentration of 20% was added to PH-
13, the solid content was filtered after 30 minutes and the nickel in the waste water was measured at 0.9 PPm, and the phosphorus was measured at 1 PPm. ,
【０００１１】[00011]
（１）廃液処理に要する時間が短い。 （２）ニツケルイオン及びリンイオンの除去効率が優れ
ている。 （３）特種な薬品を必要としない。 （４）本発明方式により重金属を除外化した後の排水は
重金属イオンを殆ど含まない。ＣＯＤの放流規制がある
場合は直流電気分解を別記の通り行えば、短時間で無害
水として放流可能である。(1) The time required for waste liquid treatment is short. (2) The removal efficiency of nickel ions and phosphorus ions is excellent. (3) No special chemical is required. (4) The waste water after the heavy metals are excluded by the method of the present invention contains almost no heavy metal ions. If there is a COD discharge regulation, direct current electrolysis can be performed as described below to discharge the harmless water in a short time.
Claims (1)
化剤、を含有する、無電解ニツケルメツキ廃液に塩酸を
混合してＰＨを調整し、還元鉄に一定時間接触すると、
液中に含有している、次亜燐酸イオンは、亜燐酸、燐
酸、の順に還元を誘起し次亜燐酸イオンを強制約に分解
する、還元鉄の溶解した液体にカセイソーダを添加して
中和し、水酸化ニツケルを生成させ、ニツケルと錯塩化
している燐イオンは鉄イオンに置換反応して、リン酸鉄
となり、水酸化ニツケルを生成すると共に凝集分離する
ことよりなる、ニツケルイオン、次亜燐酸イオン、有機
錯化剤を含有する、無電解ニツケル廃液の処理方法。1. An electroless nickel smelt waste liquid containing nickel ions, hypophosphite ions, and an organic complexing agent is mixed with hydrochloric acid to adjust the pH, and when the reduced iron is contacted for a certain period of time,
The hypophosphite ion contained in the liquid induces reduction in the order of phosphorous acid and phosphoric acid, and decomposes the hypophosphite ion into about forcibly. Neutralize by adding caustic soda to the liquid in which reduced iron is dissolved. Then, nickel hydroxide is formed, and the phosphorus ion complexed with nickel is replaced with iron ion to form iron phosphate, which forms nickel hydroxide and aggregates and separates. A method for treating an electroless nickel waste liquid containing a phosphate ion and an organic complexing agent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5341081A JPH08199366A (en) | 1993-12-01 | 1993-12-01 | Treatment of waste electroless nickel plating solution |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5341081A JPH08199366A (en) | 1993-12-01 | 1993-12-01 | Treatment of waste electroless nickel plating solution |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH08199366A true JPH08199366A (en) | 1996-08-06 |
Family
ID=18343078
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5341081A Pending JPH08199366A (en) | 1993-12-01 | 1993-12-01 | Treatment of waste electroless nickel plating solution |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH08199366A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100686985B1 (en) * | 2004-05-10 | 2007-02-27 | 박재호 | The nickel collecting method from waste nickel fluid and oxidic acid nickel sludge |
| JP2007521402A (en) * | 2003-12-31 | 2007-08-02 | ザ・ビーオーシー・グループ・インコーポレーテッド | Method for treating metal-containing solution |
| CN116425134A (en) * | 2023-02-10 | 2023-07-14 | 乐清力川环保科技有限公司 | Method for preparing super-battery-level ferric phosphate by using chemical nickel plating aging liquid |
-
1993
- 1993-12-01 JP JP5341081A patent/JPH08199366A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007521402A (en) * | 2003-12-31 | 2007-08-02 | ザ・ビーオーシー・グループ・インコーポレーテッド | Method for treating metal-containing solution |
| KR100686985B1 (en) * | 2004-05-10 | 2007-02-27 | 박재호 | The nickel collecting method from waste nickel fluid and oxidic acid nickel sludge |
| CN116425134A (en) * | 2023-02-10 | 2023-07-14 | 乐清力川环保科技有限公司 | Method for preparing super-battery-level ferric phosphate by using chemical nickel plating aging liquid |
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