KR970002898B1 - Recovery of zinc chloride from zinc ash or zinc flux - Google Patents
Recovery of zinc chloride from zinc ash or zinc flux Download PDFInfo
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- KR970002898B1 KR970002898B1 KR1019940003364A KR19940003364A KR970002898B1 KR 970002898 B1 KR970002898 B1 KR 970002898B1 KR 1019940003364 A KR1019940003364 A KR 1019940003364A KR 19940003364 A KR19940003364 A KR 19940003364A KR 970002898 B1 KR970002898 B1 KR 970002898B1
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Abstract
Description
본 발명은 아연재, 아연플럭스(ZnO·Zn(OH)C1·NH4C1)로부터 고순도의 염화아연을 회수하는 방법에 관한 것이다.The present invention relates to a method for recovering high purity zinc chloride from a zinc material and zinc flux (ZnO.Zn (OH) C1.NH 4 C1).
아연은 습기 있는 공기 중에서 쉽게 산화되어 점착성이 강한 염기성 탄산염의 피막을 형성한다.Zinc is easily oxidized in humid air to form a film of sticky basic carbonate.
2Zn+O2+H2O+CO2→ ZnCO3·Zn(OH)2 2Zn + O 2 + H 2 O + CO 2 → ZnCO 3 · Zn (OH) 2
이 피막은 금속이 그 이상 침식되는 것을 막고, 금속을 보호하게 된다. 아연은 철과 같이 쉽게 산화되는 금속을 도금하는데 유용하게 사용되고 있다. 더욱이 중공업이 발달하게 됨에 따라 강관회사 등에서 아연도금을 하는 것이 거의 필수적 공정으로 되고 있으며, 근래의 아연 도금은 염화아연을 염화암모늄과 플럭스를 형성하여 수행하고 있다. 이러한 도금공정에서 부생물로 발생하는 아연재, 아연플럭스에는 다량의 염화암모늄의 동반이 필히 따르게 된다. 즉, 아연도금욕 표면에 살포한 염화아연암모늄, 표면 세척용 약품인 암모늄단독의 과다 사용으로 인함 염화암모늄이 다량 함유된 아연재 및(또는) 아연플럭스가 발생하게 되며, 이들 부산물을 분석해 본 결과, 평균 5∼15%의 암모늄 화합물이 존재하고 있다. 그런데 이렇게 함유된 암모늄 화합물은 고순도 염화아연을 합성생산하는데 항상 장해요인으로 되어 왔다 즉, 암모늄 화합물을 함유하는 아연재나 아연플럭스는 그의 발생원에 따라 차이가 있으나, Zn(OH)C1, ZnO·NH4C1, ZnC12·NH4C1, ZnO, 납, 칠 화합물 등과 같이 복염의 형태나 기타 금속성분으로 혼합되어 있으며, 이중 특히, 복염의 형태인 Zn(OH)C1, ZnO·NH4C1, ZnC12·NH4C1 등은 암모니아 성분이 용이하게 떨어지지 않기 때문에 아연재나 아연플럭스로부터 고순도 염화아연이나 아연을 회수하는 것은 매우 곤란하였다.This coating prevents the metal from further erosion and protects the metal. Zinc is useful for plating metals that are easily oxidized, such as iron. Moreover, with the development of heavy industry, galvanizing has become an almost essential process in steel pipe companies. In recent years, zinc plating is performed by forming zinc chloride with flux with ammonium chloride. Zinc material and zinc flux generated as by-products in this plating process is accompanied by a large amount of ammonium chloride. In other words, zinc ammonium chloride and / or zinc flux containing a large amount of ammonium chloride are generated due to excessive use of zinc ammonium chloride sprayed on the surface of the galvanizing bath and ammonium alone as a surface cleaning agent. An average of 5 to 15% of ammonium compounds is present. However, the ammonium compound thus contained has always been a barrier to the synthesis and production of high-purity zinc chloride. That is, zinc materials or zinc fluxes containing ammonium compounds vary depending on their source, but Zn (OH) C1, ZnO.NH 4 C1, ZnC 12 · NH 4 C1, ZnO, lead, is mixed in the form of a double salt or other metal components, such as compounds, among others, Zn (OH) C1, ZnO · NH 4 C1, ZnC Since 12.NH 4 C1 or the like does not easily fall off of the ammonia component, it is very difficult to recover high-purity zinc chloride or zinc from the zinc material or the zinc flux.
따라서, 종래, 이들 불순물이 다량 함유된 아연재, 아연플럭스로부터 염화아연을 회수하기 위하여 소위 고온 배스(Bath)법, 즉, 아연재, 아연플력스 등을 1000∼1500℃의 고온에서 가열하여 암모늄을 승화, 분해법으로 제거한 후, 이를 처리하여 순도가 높은 아연재를 만든 후, 이로부터 염화아연을 제조하였다. 그러나, 이러한 종래의 방법으로는 98% 이상의 고순도의 염화아연을 제조할 수 없었다 또한 이러한 방법은 공해가 발생하고, 그의 처리 비용이 과다하고, 고온 가열로 및 그의 흡수 유도체들의 공해방지 설비에 대한 투자비 및 이들 설비의 부식에 의한 시설 유지비가 과다하게 소요되고, 또한 에너지의 소모가 많아서 제조원가가 높게되는 원인으로 되는 등의 결점이 있었다.Therefore, in order to recover zinc chloride from zinc materials and zinc fluxes containing a large amount of these impurities, a so-called high temperature bath method, that is, zinc materials, zinc fluxes, and the like are heated at a high temperature of 1000 to 1500 ° C. After removal by sublimation and decomposition method, it was treated to make a high purity zinc material, and zinc chloride was prepared therefrom. However, such a conventional method could not produce high purity zinc chloride of more than 98%. In addition, this method has pollution, its treatment cost is excessive, and the investment cost for the pollution prevention facility of the high temperature furnace and its absorption derivatives is high. In addition, there are drawbacks such as excessive facility maintenance costs due to corrosion of these facilities, high energy consumption, and high manufacturing costs.
본 발명자는 상기의 문제점을 해결하기 위하여 예의 연구 검토한 결과, 아연재, 아연플럭스의 원료에 염산을 가하여 액화시켜서 염화아연·암모늄(ZnC12·NH4Cl)의 액체 형태로 만든 후, 질산아연을 가하여 염화아연과 질산암모늄으로 복분해시키고, 얻어진 용액을 240∼300℃에서 가열 농축하여 질산암모늄을 질소, NO, NO2상태로 열분해하고, 이를 기상에서 중화 흡수시키고, 농축된 염화아연은 물에 용해시켜 통상의 정제방법으로 정제하여 고순도의 염화아연을 액상으로 얻을 수 있음을 발견하고 본 발명을 완성하게 되었다.In order to solve the above problems, the present inventors have studied diligently and liquefied by adding hydrochloric acid to the raw material of zinc materials and zinc flux, and then made into a liquid form of zinc chloride and ammonium (ZnC 12 · NH 4 Cl), followed by zinc nitrate. The solution was metathesized into zinc chloride and ammonium nitrate, and the resulting solution was concentrated by heating at 240 to 300 ° C. to thermally decompose ammonium nitrate into nitrogen, NO and NO 2 states, neutralized and absorbed in the gas phase, and the concentrated zinc chloride was dissolved in water. The present invention was completed by discovering that zinc chloride of high purity can be obtained by dissolving and purifying by a conventional purification method in a liquid phase.
이하 본 발명을 상세히 설명한다.Hereinafter, the present invention will be described in detail.
본 발명은 강관회사 등에서 배출되는 염화암모늄이 함유된 아연재, 아연플럭스의 원료에 염산을 가해 액화시킨다. 이때 사용되는 염산의 농도는 특별히 한정되는 것은 아니나, 공정의 용이성 때문에 농염산(약 35%)을 사용하여, 그의 첨가량은 원료인 아연재, 아연플럭스의 아연에 상응하는 당량의 염산을 첨가한다.The present invention is liquefied by adding hydrochloric acid to the raw material of the zinc material, zinc flux containing ammonium chloride discharged from steel pipe companies and the like. At this time, the concentration of hydrochloric acid to be used is not particularly limited, but concentrated hydrochloric acid (about 35%) is used because of the ease of the process, the addition amount of the hydrochloric acid corresponding to the zinc material, zinc flux zinc zinc is added.
액화된 액은 염화아연 암모늄의 성분으로서 ZnC12·NH4Cl의 분자형태로 용해된다. 평균농도는 염화아연의 품위로 약 50%, 염화암모늄은 약 5∼10% 존재하나, 원료에 따라 일정하지 않다.The liquefied liquid is dissolved in the molecular form of ZnC1 2 NH 4 Cl as a component of zinc ammonium chloride. The average concentration is about 50% zinc chloride grade and about 5-10% ammonium chloride, but it is not constant depending on the raw materials.
이렇게 얻어진 액체의 성분을 정량분석하여 염화암모늄의 함유량을 측정하여 이와 반응하는 질산아연을 첨가하여 반응시킨다 이 반응은 반응식으로 나타내면 아래와 같다.The components of the liquid thus obtained are quantitatively analyzed, the content of ammonium chloride is measured, and zinc nitrate reacted with the reaction is added. The reaction is represented by the following equation.
2NH4C1+Zn(NO3)2→ ZnC12+2NH4NO3상기 반응식에 나타난 바와 같이 염화암모늄은 질산아연과 반응하여 염화아연과 질산암모늄을 생성하게 된다. 이때 첨가되는 질산아연의 양은 염화암모늄의 양에 대해 12∼2.0몰비량, 바람직하기로는 1.2∼1.7몰비량이다. 이렇게 약간 과량의 질산아연을 가하여도 후술하는 열분해 공정에 의해 모두 제거되기 때문에 하등의 지장이 없다.2NH 4 C1 + Zn (NO 3 ) 2 → ZnC 12 + 2NH 4 NO 3 As shown in the above scheme, ammonium chloride reacts with zinc nitrate to produce zinc chloride and ammonium nitrate. The amount of zinc nitrate added at this time is 12 to 2.0 molar ratio, preferably 1.2 to 1.7 molar ratio with respect to the amount of ammonium chloride. Thus, even if a slight excess of zinc nitrate is removed by the thermal decomposition process described later, there is no problem.
이렇게 얻어진 용액을 240∼300℃에서 가열 농축하면 질산암모늄은 열분해하여 질소, NO, NO2상태로 열분해되고 이를 기상(氣相)에서 중화 흡수시켜 처리한다.When the solution thus obtained is heated and concentrated at 240 to 300 ° C., ammonium nitrate is thermally decomposed to be thermally decomposed into nitrogen, NO, and NO 2 states, and neutralized and absorbed in a gas phase to be treated.
상기에서 얻어진 농축된 염화아연 용융액에 물을 가하여 다시 용해시키고, 탈철 및 여과하여 고순도의 액체를 50∼55%의 농도로 얻는다.Water was added to the concentrated zinc chloride melt obtained above to dissolve again, de-ironed and filtered to obtain a liquid of high purity at a concentration of 50 to 55%.
또한, 상기의 방법에서 아연재나 아연플럭스를 염산을 가해 염화아연으로 생성 반응시킬 때, 일부의 미반응의 아연재나 아연플럭스가 잔존하도록, 염산량을 약간 적게 넣고, 다음 반응인 질산아연을 가하는 대신에 질산을 가하면 잔존하는 산화아연과 반응하여 질산아연과 물이 생성되고 질산아연을 염화암모늄과 반응하여 염화아연을 생성하개 된다. 따라서 동일 반응기중에서 염화아연과 질산암모늄이 함유된 액상물을 생성하며,In the above method, when the zinc material or the zinc flux is added with hydrochloric acid to react with zinc chloride, a small amount of hydrochloric acid is added so that some unreacted zinc material or zinc flux remains, and the next reaction is zinc nitrate. Instead of adding nitric acid, zinc nitrate and water react with the remaining zinc oxide and zinc nitrate reacts with ammonium chloride to produce zinc chloride. Therefore, in the same reactor to produce a liquid containing zinc chloride and ammonium nitrate,
이를 열분해시킴으로서 목적으로 하는 염화아연을 얻게 된다.By pyrolyzing this, the desired zinc chloride is obtained.
이러한 방법의 잇점으로서는 별도의 질산아연을 첨가할 필요없이 소량의 질산을 가해 미반응 산화아연과 반응시켜 질산아연을 동일 반응기에서 생성시켜, 이를 적접 염화암모늄과 반응시킴으로서 반응시간, 반응비용을 절감할 수 있다.As an advantage of this method, a small amount of nitric acid is added to react with unreacted zinc oxide without the need to add a separate zinc nitrate to produce zinc nitrate in the same reactor. Can be.
상기 반응에서 첨가하는 질산의 양은 용액중에 잔존하는 염화암모늄과 반응할 수 있는 양이면 충분하다.The amount of nitric acid added in the reaction is sufficient to react with the ammonium chloride remaining in the solution.
이를 반응식으로 나타내면 다음과 같다.This is represented by the following scheme.
ZnO+2HC1→ ZnC12H2OZnO + 2HC1 → ZnC 12 H 2 O
ZnO+2HNO3→ Zn(NO3)2+H2OZnO + 2HNO 3 → Zn (NO3) 2 + H 2 O
Zn(NO3)2+2NH4Cl→ZnC12+2NH4NO3 Zn (NO 3 ) 2 + 2NH 4 Cl → ZnC 12 + 2NH 4 NO 3
이하 실시예로서 본 발명을 더 구체적으로 설명한다. 그러나 이들 실시예에 의해 본 발명의 범위가 한정되는 것은 아니다.The present invention will be described in more detail with reference to the following Examples. However, the scope of the present invention is not limited by these Examples.
(실시예 1)(Example 1)
강관회사에서 배출된 아연재(아연화(ZnO) 함량 635%, 염화암모늄 함량 13%) lkg에 35% 염산을 서서히 첨가하여 액화시켰다(이때 과량의 염산이 첨가된 경우에는 아연재를 첨가하며 중화시킨다) 이렇게 하여 염화아연 1, 0656g 및 염화암모늄 130g이 존재하는 복염 상태의 액체를 만들고, 230g의 무수 질산아연을 첨가하고, 240∼300℃에서 가열 농축하여 염화암모늄을 제거하고, 정제한 아연액중의 염화암모늄(NH4C1)은 분석한 결과 0001% 이하이었고, 얻어진 염화아연의 순도는 약 994%이었으며, 수득량은 1007.0g(수율 : 약94.5%)이었다.35 kg hydrochloric acid was slowly liquefied to lkg of zinc material (ZnO content 635%, ammonium chloride content 13%) discharged from the steel pipe company. (In case of excess hydrochloric acid, zinc material is added and neutralized.) In this way, a double salt liquid containing 1, 0656 g of zinc chloride and 130 g of ammonium chloride was prepared, 230 g of anhydrous zinc nitrate was added, and concentrated at 240 to 300 ° C. to remove ammonium chloride, and in a purified zinc liquid. Ammonium chloride (NH 4 C1) of was analyzed to be less than 0001%, the purity of the obtained zinc chloride was about 994%, the yield was 1007.0g (yield: about 94.5%).
(실시예 2)(Example 2)
배출원이 상이한 아연플럭스(아연화(ZnO) 함량 67.7%, 염화암모늄 함량 15%) lkg을 실시예 1과 동일하게 35% 염산으로 서서히 액화시켰다. 이렇게 하여 염화아연 1, 136g 및 염화암모늄 150g이 존재하는 복염상태의 액상물을 얻고, 여기에 398g의 무수 질산아연을 첨가하고, 240∼300℃에서 가열 농축하여 염화암모늄을 제거하고, 정제한 아연액중의 염화암모늄(NH.C1)은 분석한 결과 00001% 이하이었고, 얻어진 염화아연의 순도는 약 992%이었으며, 수득량은 1068g(수율 약 94%)이었다.1 kg of zinc flux (ZnO content 67.7%, ammonium chloride content 15%) with different sources was slowly liquefied with 35% hydrochloric acid as in Example 1. In this way, a double-chloride liquid product containing 1, 136 g of zinc chloride and 150 g of ammonium chloride was obtained, and 398 g of anhydrous zinc nitrate was added thereto, concentrated by heating at 240 to 300 ° C. to remove ammonium chloride, and purified zinc. Ammonium chloride (NH.C1) in the liquid was analyzed to be less than 00001%. The purity of the obtained zinc chloride was about 992%, and the yield was 1068 g (yield about 94%).
(실시예 3)(Example 3)
실시예 1과 같이하여 얻은 염화아연 및 염화암모늄이 존재하는 복염 50%의 액체에 283g의 무수 질산아연(몰비로 144배)을 첨가하고, 240∼300℃에서 가열능축하여 염화암모늄을 분해 제거하고 얻은 염화아연을 정제하여 염화암모늄의 존재를 분석한 결과, 검출되지 않았다. 또한 염화아연의 순도는 996%이었고, 그의 수득량은 10486g(수율 약 95%)이었다.283 g of anhydrous zinc nitrate (144 times in molar ratio) was added to a double salt 50% liquid containing zinc chloride and ammonium chloride obtained in the same manner as in Example 1, and thermally cured at 240 to 300 DEG C to decompose and remove ammonium chloride. The zinc chloride obtained was purified and analyzed for the presence of ammonium chloride, which was not detected. The purity of zinc chloride was 996%, and the yield thereof was 10486 g (about 95% yield).
(실시예 4)(Example 4)
실시예 1과 동일한 원료 1, 180g에 35% 염산을 서서히 첨가하여 액화반응시키면서 반응 진행율이 약 80%되었을 때, 60% 질산 300g을 넣고 반응을 완료시켰다 이렇게 하여 염화아연 1, 0656g과 염화암모늄 l30g과 질산아연 230g(몰비의 117배)이 존재하는 복염상태의 액체를 만들고, 240∼300℃에서 가열 농축하여 염화암모늄을 제거하고, 정제한 염화아연중의 염화암모늄을 분석한 결과, 00001% 이하이었고, 얻어진 염화아연의 순도는 992%이고, 수득량은 l0l2g(수율 95%)이었다.35% hydrochloric acid was slowly added to 180 g of the same raw material as in Example 1 to liquefy the reaction, and the reaction progress was about 80%. Then, 300 g of 60% nitric acid was added to complete the reaction. Zinc chloride 1, 0656 g and ammonium chloride l30 g A double salt liquid containing 230 g of zinc nitrate (117 times the molar ratio) was formed, and the mixture was heated and concentrated at 240 to 300 ° C. to remove ammonium chloride. Analysis of ammonium chloride in purified zinc chloride resulted in less than 00001%. The purity of the obtained zinc chloride was 992%, and the yield was 1001 g (yield 95%).
상기 실시예 2에서는 실시예 1 및 3보다 염화암모늄의 양에 대해 17배 몰비량으로 첨가한 것은 염화암모늄을 완전히 제거할 목적으로 과량첨가한 것이며, 실시예 2의 생성물을 분석한 결과에 나타난 바와 같이 염화암모늄의 양에 대해 과량의 질산아연을 첨가하여 염화아연을 완전히 제거, 분해시킬 수 있음을 나타내며, 실시예 4는 질산아연 대신 질산을 사용하여도 동일한 효과를 얻을 수 있다는 것을 알 수 있으며, 또함 과량의 질산아연은 240∼300℃에서 그 자체 열분해되어 NO, NO2및 ZnO의 형태로 되는 장점이 있다.In Example 2, the addition of a molar ratio of 17 times to the amount of ammonium chloride than Examples 1 and 3 was added in an excessive amount for the purpose of completely removing ammonium chloride, as shown in the results of analyzing the product of Example 2. Likewise, zinc chloride can be completely removed and decomposed by adding excess zinc nitrate to the amount of ammonium chloride. Example 4 shows that the same effect can be obtained by using nitric acid instead of zinc nitrate. In addition, the excess zinc nitrate has the advantage of thermally decomposing itself at 240 ~ 300 ℃ in the form of NO, NO 2 and ZnO.
이상에서 설명한 바와 같이 본 발명에 의하면 저렴한 원료로부터 고순도의 염화아연을 저렴하고 간편하게 회수할 수 있다.As described above, according to the present invention, high-purity zinc chloride can be recovered at low cost and easily.
Claims (3)
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| Application Number | Priority Date | Filing Date | Title |
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| KR1019940003364A KR970002898B1 (en) | 1994-02-24 | 1994-02-24 | Recovery of zinc chloride from zinc ash or zinc flux |
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| KR1019940003364A KR970002898B1 (en) | 1994-02-24 | 1994-02-24 | Recovery of zinc chloride from zinc ash or zinc flux |
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| KR100311772B1 (en) * | 1999-12-14 | 2001-10-17 | 김명제 | Manufacturing method of flux solution using waste acid containing zinc |
| KR100625521B1 (en) * | 2005-06-21 | 2006-09-20 | 심재윤 | Production of ultra fine zinc oxide particle from zinc ash and the products thereby |
| KR102002052B1 (en) | 2017-12-22 | 2019-07-19 | (주)세화브이엘 | Method for recycling a waste acid containing zinc |
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