CN104760938A - Method for removing iron ions from concentrated sulfuric acid - Google Patents
Method for removing iron ions from concentrated sulfuric acid Download PDFInfo
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- CN104760938A CN104760938A CN201510132190.7A CN201510132190A CN104760938A CN 104760938 A CN104760938 A CN 104760938A CN 201510132190 A CN201510132190 A CN 201510132190A CN 104760938 A CN104760938 A CN 104760938A
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- sulfuric acid
- concentrated sulfuric
- iron ions
- methylimidazole
- ethyl
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 34
- 229910052742 iron Inorganic materials 0.000 title claims abstract description 27
- 238000000034 method Methods 0.000 title claims abstract description 25
- QAOWNCQODCNURD-UHFFFAOYSA-N sulfuric acid Substances OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 title abstract description 25
- -1 iron ions Chemical class 0.000 title abstract description 19
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 15
- 238000000605 extraction Methods 0.000 claims abstract description 13
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 12
- 239000012074 organic phase Substances 0.000 claims abstract description 10
- 239000002608 ionic liquid Substances 0.000 claims abstract description 6
- 239000000284 extract Substances 0.000 claims abstract description 4
- 238000006243 chemical reaction Methods 0.000 claims description 7
- IBZJNLWLRUHZIX-UHFFFAOYSA-N 1-ethyl-3-methyl-2h-imidazole Chemical compound CCN1CN(C)C=C1 IBZJNLWLRUHZIX-UHFFFAOYSA-N 0.000 claims description 5
- 239000003795 chemical substances by application Substances 0.000 claims description 4
- 238000005660 chlorination reaction Methods 0.000 claims description 4
- 239000002994 raw material Substances 0.000 claims description 3
- 230000003068 static effect Effects 0.000 claims description 2
- 238000013019 agitation Methods 0.000 claims 1
- 150000001875 compounds Chemical class 0.000 claims 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 claims 1
- 230000035484 reaction time Effects 0.000 claims 1
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 abstract description 8
- 229960004887 ferric hydroxide Drugs 0.000 abstract description 4
- 239000012535 impurity Substances 0.000 abstract description 4
- IEECXTSVVFWGSE-UHFFFAOYSA-M iron(3+);oxygen(2-);hydroxide Chemical compound [OH-].[O-2].[Fe+3] IEECXTSVVFWGSE-UHFFFAOYSA-M 0.000 abstract description 4
- 239000003208 petroleum Substances 0.000 abstract description 4
- FQERWQCDIIMLHB-UHFFFAOYSA-N 1-ethyl-3-methyl-1,2-dihydroimidazol-1-ium;chloride Chemical compound [Cl-].CC[NH+]1CN(C)C=C1 FQERWQCDIIMLHB-UHFFFAOYSA-N 0.000 abstract description 3
- 238000003760 magnetic stirring Methods 0.000 abstract description 2
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical compound [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 abstract 1
- MGFYFCSBZOXCHM-UHFFFAOYSA-N chloroethane;1-methylimidazole Chemical compound CCCl.CN1C=CN=C1 MGFYFCSBZOXCHM-UHFFFAOYSA-N 0.000 abstract 1
- 229910001447 ferric ion Inorganic materials 0.000 abstract 1
- 238000005516 engineering process Methods 0.000 description 5
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- BMQZYMYBQZGEEY-UHFFFAOYSA-M 1-ethyl-3-methylimidazolium chloride Chemical compound [Cl-].CCN1C=C[N+](C)=C1 BMQZYMYBQZGEEY-UHFFFAOYSA-M 0.000 description 3
- NJMWOUFKYKNWDW-UHFFFAOYSA-N 1-ethyl-3-methylimidazolium Chemical compound CCN1C=C[N+](C)=C1 NJMWOUFKYKNWDW-UHFFFAOYSA-N 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 238000010668 complexation reaction Methods 0.000 description 2
- 238000004821 distillation Methods 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 description 1
- UINDRJHZBAGQFD-UHFFFAOYSA-N 2-ethyl-1-methylimidazole Chemical compound CCC1=NC=CN1C UINDRJHZBAGQFD-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000001479 atomic absorption spectroscopy Methods 0.000 description 1
- 239000003729 cation exchange resin Substances 0.000 description 1
- 238000012993 chemical processing Methods 0.000 description 1
- 238000012824 chemical production Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- MVZXTUSAYBWAAM-UHFFFAOYSA-N iron;sulfuric acid Chemical compound [Fe].OS(O)(=O)=O MVZXTUSAYBWAAM-UHFFFAOYSA-N 0.000 description 1
- 238000009853 pyrometallurgy Methods 0.000 description 1
- 239000001054 red pigment Substances 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
本发明涉及一种去除浓硫酸中铁离子的反应萃取方法，该方法通过将一种离子液体(氯化1-乙基-3-甲基咪唑纯度为99％)与浓盐酸加入至含铁离子的浓硫酸中，50℃油浴，磁力搅拌，与铁离子反应1.5个小时，然后加入石油醚进行萃取，同时利用氢氧化钠对有机相进行反萃取，得到氢氧化铁、氯化1-乙基-3-甲基咪唑和萃取剂，离子液体和萃取剂循环使用，浓硫酸中铁离子的去除率可达85％左右。本发明具有：设备投资小、工艺条件温和、易操作、成本低、带入的杂质少等优点。The invention relates to a reactive extraction method for removing iron ions in concentrated sulfuric acid, the method is by adding an ionic liquid (the purity of 1-ethyl-3-methylimidazole chloride is 99%) and concentrated hydrochloric acid to the ferric ion-containing In concentrated sulfuric acid, 50 ° C oil bath, magnetic stirring, react with iron ions for 1.5 hours, then add petroleum ether for extraction, and use sodium hydroxide to back-extract the organic phase to obtain ferric hydroxide, 1-ethyl chloride - 3-methylimidazole and extractant, ionic liquid and extractant are recycled, and the removal rate of iron ions in concentrated sulfuric acid can reach about 85%. The invention has the advantages of small equipment investment, mild process conditions, easy operation, low cost, less impurities brought in, and the like.
Description
技术领域technical field
本发明涉及一种反应萃取技术，尤其是涉及一种去除浓硫酸中铁离子所使用的反应萃取技术。The invention relates to a reactive extraction technology, in particular to a reactive extraction technology used for removing iron ions in concentrated sulfuric acid.
背景技术Background technique
目前，在化学生产加工工艺中，浓硫酸是一种重要的原料，像蓄电池电解液，而浓硫酸在生产或运输过程会产生或参有少量铁离子，影响产品使用和档次。随着现代生产工艺或下游生产工艺的要求越来越高，厂家要求有一种产品能在其工艺基本不变的前提下去除铁离子含量。目前去除铁离子的方法主要有阳离子交换树脂，双氧水法，蒸馏法。但这些方法成本大(如由于酸液中杂质的影响，树脂寿命较短，更换频次有时候较高，成本大)，双氧水法不好控制加料量，蒸馏法工艺繁琐，投资成本过高。而铁离子能与离子液体生成络合物，采取离子液体反应萃取方法去除浓硫酸中铁离子具有：设备投资小、工艺条件温和、易操作、成本低、带入的杂质少等优点。利用反应萃取法分离浓硫酸中的铁离子，不仅可以改进除铁工艺，而且利用副产物氢氧化铁还可以得到氧化铁红颜料，对于硫酸行业的可持续发展具有重要的现实意义。At present, in the chemical production and processing technology, concentrated sulfuric acid is an important raw material, such as battery electrolyte, and concentrated sulfuric acid will produce or participate in a small amount of iron ions during the production or transportation process, which will affect the use and grade of the product. With the increasing requirements of modern production technology or downstream production technology, manufacturers require a product that can remove iron ion content under the premise that its technology is basically unchanged. At present, the methods for removing iron ions mainly include cation exchange resin, hydrogen peroxide method, and distillation method. However, these methods are costly (such as due to the influence of impurities in the acid solution, the resin life is short, the frequency of replacement is sometimes high, and the cost is high), the hydrogen peroxide method is not easy to control the amount of feed, the distillation process is cumbersome, and the investment cost is too high. However, iron ions can form complexes with ionic liquids. The removal of iron ions in concentrated sulfuric acid by using ionic liquid reaction extraction method has the advantages of small equipment investment, mild process conditions, easy operation, low cost, and less impurities. The separation of iron ions in concentrated sulfuric acid by reactive extraction can not only improve the iron removal process, but also obtain iron oxide red pigment by using the by-product ferric hydroxide, which has important practical significance for the sustainable development of the sulfuric acid industry.
发明内容Contents of the invention
针对目前浓硫酸除铁工艺存在的不足之处，本发明提供一种反应萃取技术去除铁离子的方法，可有效简化浓硫酸中铁离子去除程序，进一步提高浓硫酸的性能。Aiming at the shortcomings of the current concentrated sulfuric acid iron removal process, the present invention provides a method for removing iron ions by reactive extraction technology, which can effectively simplify the removal procedure of iron ions in concentrated sulfuric acid and further improve the performance of concentrated sulfuric acid.
本发明方法的工艺过程如下。The technological process of the inventive method is as follows.
以火法炼铜副产的浓硫酸为原料，按质量百分比计，铁离子含量为万分之八到万分之十。采用反应萃取除铁，向浓硫酸依次加入浓盐酸，氯化1-乙基-3-甲基咪唑([EMIM]Cl)进行络合反应，浓盐酸加入量为0.8-1.0毫升，氯化1-乙基-3-甲基咪唑加入量为0.4-0.5克，50℃油浴，磁力搅拌，反应1.5小时后，用石油醚进行萃取，充分振荡，静止，分层，得到非有机相为浓硫酸溶液，得到有机相为含铁的络合物和萃取剂，而后加入质量浓度为10％氢氧化钠溶液对有机相进行反萃取，控制氢氧化钠溶液的加入量为有机相体积的7％-10％，调节pH值为9，充分振荡，静置，分层，得到氢氧化铁、氯化1-乙基-3-甲基咪唑和萃取剂，离子液体萃取剂循环使用。利用原子吸收光度法测定铁离子的浓度，浓硫酸中铁离子的去除率可达为85％左右。Concentrated sulfuric acid, a by-product of pyrometallurgy, is used as raw material, and the content of iron ions is 8 to 10 ten thousandths by mass percentage. Use reaction extraction to remove iron, add concentrated hydrochloric acid to concentrated sulfuric acid successively, and chlorinate 1-ethyl-3-methylimidazole ([EMIM]Cl) for complexation reaction, the amount of concentrated hydrochloric acid added is 0.8-1.0 ml, chlorination 1 - The amount of ethyl-3-methylimidazole is 0.4-0.5 g, 50 ° C oil bath, magnetic stirring, after 1.5 hours of reaction, extract with petroleum ether, fully shake, stand still, and separate layers to obtain the non-organic phase as concentrated Sulfuric acid solution, the organic phase obtained is iron-containing complex and extractant, and then adding mass concentration is 10% sodium hydroxide solution to back-extract the organic phase, controlling the addition of sodium hydroxide solution to be 7% of the organic phase volume -10%, adjust the pH value to 9, fully shake, stand still, and separate layers to obtain ferric hydroxide, 1-ethyl-3-methylimidazole chloride and extractant, and the ionic liquid extractant is recycled. Using atomic absorption spectrometry to measure the concentration of iron ions, the removal rate of iron ions in concentrated sulfuric acid can reach about 85%.
本发明的原理反应如下：Principle of the present invention reacts as follows:
首先在浓硫酸中发生络合反应，然后利用石油醚进行萃取，对有机相进行反萃取，其反应式为：First, a complexation reaction occurs in concentrated sulfuric acid, and then the petroleum ether is used for extraction, and the organic phase is back-extracted. The reaction formula is:
[EMIM]Cl+3HCl+Fe3+→[EMIM]FeCl4+3H- [EMIM]Cl+3HCl+Fe 3+ →[EMIM]FeCl 4 +3H -
[EMIM]FeCl4+3NaOH→[EMIM]Cl+3NaCl+Fe(OH)3↓[EMIM]FeCl 4 +3NaOH→[EMIM]Cl+3NaCl+Fe(OH) 3 ↓
本发明与其它相关去除技术相比，最显著的特点是：工艺流程简单，设备投资小，反应条件易于控制，工艺条件要求低，带入的杂质少，所制得的浓硫酸能够满足像蓄电池生产中对浓硫酸的要求。Compared with other related removal technologies, the present invention has the most notable features: simple process flow, small investment in equipment, easy control of reaction conditions, low requirements on process conditions, less impurities brought in, and the prepared concentrated sulfuric acid can meet the requirements of storage batteries. Requirements for concentrated sulfuric acid in production.
附图说明Description of drawings
图1是本发明中去除浓硫酸中铁离子的工艺流程图。Fig. 1 is the process flow diagram of removing iron ion in the concentrated sulfuric acid among the present invention.
具体实施方式Detailed ways
移取100毫升铁离子含量为0.0009(质量百分比)的浓硫酸于400毫升烧杯中，加入0.8毫升浓盐酸，加入氯化1-乙基-3-甲基咪唑0.45克，置50℃油浴中，磁力搅拌，反应1.5小时后，用40毫升石油醚进行萃取，充分振荡，静止，分层，得到非有机相为浓硫酸溶液，得到有机相为含铁的络合物和萃取剂，而后加入3.5毫升质量浓度为10％氢氧化钠溶液对有机相进行反萃取，充分振荡，静置，分层，得到氢氧化铁、氯化1-乙基-3-甲基咪唑和萃取剂，浓硫酸中铁离子的去除率为85.2％。Pipette 100 milliliters of concentrated sulfuric acid with an iron ion content of 0.0009 (mass percentage) in a 400 milliliter beaker, add 0.8 milliliters of concentrated hydrochloric acid, add 0.45 grams of 1-ethyl-3-methylimidazole chloride, and place in a 50°C oil bath , magnetically stirred, after 1.5 hours of reaction, extracted with 40 ml of petroleum ether, fully oscillated, static, and layered, the non-organic phase was obtained as a concentrated sulfuric acid solution, and the organic phase was obtained as an iron-containing complex and extractant, and then added 3.5 milliliters of mass concentration is that 10% sodium hydroxide solution carries out back extraction to organic phase, fully shakes, stands, layering, obtains ferric hydroxide, chlorinated 1-ethyl-3-methylimidazole and extraction agent, concentrated sulfuric acid The removal rate of iron ions in the medium is 85.2%.
Claims (4)
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105624399A (en) * | 2016-02-04 | 2016-06-01 | 山西大学 | Method for stripping and removing iron from iron-ion-rich liquid |
| CN108179273A (en) * | 2018-01-19 | 2018-06-19 | 重庆康普化学工业股份有限公司 | A kind of method using solvent-extracted back extraction iron |
| CN110092358A (en) * | 2019-05-24 | 2019-08-06 | 华东理工大学 | A kind of processing method of waste sulfuric acid from alkylation |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1072154A (en) * | 1991-11-08 | 1993-05-19 | 日铁矿业株式会社 | The method of reclaim(ed) sulfuric acid from the sulfur waste acid of containing metal vitriol |
| CN1936035A (en) * | 2006-09-29 | 2007-03-28 | 金川集团有限公司 | P204 deferrizing regeneration method |
| CN101514165A (en) * | 2009-03-24 | 2009-08-26 | 中国科学院长春应用化学研究所 | Method for preparing liquid containing metallic ions by employing extraction reaction |
| CN103160689A (en) * | 2013-02-26 | 2013-06-19 | 中南大学 | Method of iron extraction and removal with solvent extraction agent |
-
2015
- 2015-03-18 CN CN201510132190.7A patent/CN104760938B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1072154A (en) * | 1991-11-08 | 1993-05-19 | 日铁矿业株式会社 | The method of reclaim(ed) sulfuric acid from the sulfur waste acid of containing metal vitriol |
| CN1936035A (en) * | 2006-09-29 | 2007-03-28 | 金川集团有限公司 | P204 deferrizing regeneration method |
| CN101514165A (en) * | 2009-03-24 | 2009-08-26 | 中国科学院长春应用化学研究所 | Method for preparing liquid containing metallic ions by employing extraction reaction |
| CN103160689A (en) * | 2013-02-26 | 2013-06-19 | 中南大学 | Method of iron extraction and removal with solvent extraction agent |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105624399A (en) * | 2016-02-04 | 2016-06-01 | 山西大学 | Method for stripping and removing iron from iron-ion-rich liquid |
| CN105624399B (en) * | 2016-02-04 | 2017-12-05 | 山西大学 | A kind of method that iron removaling is stripped from rich iron ion liquid |
| CN108179273A (en) * | 2018-01-19 | 2018-06-19 | 重庆康普化学工业股份有限公司 | A kind of method using solvent-extracted back extraction iron |
| CN110092358A (en) * | 2019-05-24 | 2019-08-06 | 华东理工大学 | A kind of processing method of waste sulfuric acid from alkylation |
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