JP3928650B2 - Reducing water purification material and method for producing the same - Google Patents
Reducing water purification material and method for producing the same Download PDFInfo
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- JP3928650B2 JP3928650B2 JP2005262733A JP2005262733A JP3928650B2 JP 3928650 B2 JP3928650 B2 JP 3928650B2 JP 2005262733 A JP2005262733 A JP 2005262733A JP 2005262733 A JP2005262733 A JP 2005262733A JP 3928650 B2 JP3928650 B2 JP 3928650B2
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims description 92
- 238000000746 purification Methods 0.000 title claims description 64
- 239000000463 material Substances 0.000 title claims description 59
- 230000001603 reducing effect Effects 0.000 title claims description 42
- 238000004519 manufacturing process Methods 0.000 title claims description 17
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 299
- 229910052742 iron Inorganic materials 0.000 claims description 117
- 239000002244 precipitate Substances 0.000 claims description 105
- 238000002156 mixing Methods 0.000 claims description 38
- 239000002351 wastewater Substances 0.000 claims description 37
- 239000002002 slurry Substances 0.000 claims description 34
- 229910000859 α-Fe Inorganic materials 0.000 claims description 30
- 229910000510 noble metal Inorganic materials 0.000 claims description 26
- BUGBHKTXTAQXES-UHFFFAOYSA-N Selenium Chemical compound [Se] BUGBHKTXTAQXES-UHFFFAOYSA-N 0.000 claims description 25
- 229910052711 selenium Inorganic materials 0.000 claims description 25
- 239000011669 selenium Substances 0.000 claims description 25
- 239000007788 liquid Substances 0.000 claims description 23
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 22
- 239000007864 aqueous solution Substances 0.000 claims description 22
- 229910001385 heavy metal Inorganic materials 0.000 claims description 22
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 claims description 22
- 239000003513 alkali Substances 0.000 claims description 17
- NCNCGGDMXMBVIA-UHFFFAOYSA-L iron(ii) hydroxide Chemical compound [OH-].[OH-].[Fe+2] NCNCGGDMXMBVIA-UHFFFAOYSA-L 0.000 claims description 15
- 235000014413 iron hydroxide Nutrition 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 13
- 230000001590 oxidative effect Effects 0.000 claims description 13
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 12
- 229910052802 copper Inorganic materials 0.000 claims description 12
- 239000010949 copper Substances 0.000 claims description 12
- 150000003839 salts Chemical class 0.000 claims description 12
- 229910021607 Silver chloride Inorganic materials 0.000 claims description 11
- 229910052759 nickel Inorganic materials 0.000 claims description 11
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 claims description 11
- 229910052785 arsenic Inorganic materials 0.000 claims description 10
- RQNWIZPPADIBDY-UHFFFAOYSA-N arsenic atom Chemical compound [As] RQNWIZPPADIBDY-UHFFFAOYSA-N 0.000 claims description 10
- 238000000926 separation method Methods 0.000 claims description 10
- 230000003647 oxidation Effects 0.000 claims description 9
- 238000007254 oxidation reaction Methods 0.000 claims description 9
- 239000010419 fine particle Substances 0.000 claims description 8
- 230000033116 oxidation-reduction process Effects 0.000 claims description 8
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 7
- 229910052793 cadmium Inorganic materials 0.000 claims description 7
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 claims description 7
- 229910017052 cobalt Inorganic materials 0.000 claims description 7
- 239000010941 cobalt Substances 0.000 claims description 7
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 7
- -1 ferrous compound Chemical class 0.000 claims description 7
- 229910052725 zinc Inorganic materials 0.000 claims description 7
- 239000011701 zinc Substances 0.000 claims description 7
- 229910052787 antimony Inorganic materials 0.000 claims description 5
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 claims description 5
- JOPOVCBBYLSVDA-UHFFFAOYSA-N chromium(6+) Chemical compound [Cr+6] JOPOVCBBYLSVDA-UHFFFAOYSA-N 0.000 claims description 5
- 239000011261 inert gas Substances 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 claims description 5
- 239000002184 metal Substances 0.000 claims description 5
- 239000000047 product Substances 0.000 claims description 5
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 4
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 claims description 4
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 4
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 4
- 229910052796 boron Inorganic materials 0.000 claims description 4
- 229910052731 fluorine Inorganic materials 0.000 claims description 4
- 239000011737 fluorine Substances 0.000 claims description 4
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 4
- 229910052737 gold Inorganic materials 0.000 claims description 4
- 239000010931 gold Substances 0.000 claims description 4
- 229910052750 molybdenum Inorganic materials 0.000 claims description 4
- 239000011733 molybdenum Substances 0.000 claims description 4
- 239000010970 precious metal Substances 0.000 claims description 4
- 229910052709 silver Inorganic materials 0.000 claims description 4
- 239000004332 silver Substances 0.000 claims description 4
- 239000000243 solution Substances 0.000 claims description 4
- WSLDOOZREJYCGB-UHFFFAOYSA-N 1,2-Dichloroethane Chemical group ClCCCl WSLDOOZREJYCGB-UHFFFAOYSA-N 0.000 claims description 3
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 claims description 3
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims description 3
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims description 3
- XSTXAVWGXDQKEL-UHFFFAOYSA-N Trichloroethylene Chemical group ClC=C(Cl)Cl XSTXAVWGXDQKEL-UHFFFAOYSA-N 0.000 claims description 3
- 238000005273 aeration Methods 0.000 claims description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 3
- 150000002506 iron compounds Chemical class 0.000 claims description 3
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 claims description 3
- 229910052760 oxygen Inorganic materials 0.000 claims description 3
- 239000001301 oxygen Substances 0.000 claims description 3
- 229910052698 phosphorus Inorganic materials 0.000 claims description 3
- 239000011574 phosphorus Substances 0.000 claims description 3
- 239000000126 substance Substances 0.000 claims description 3
- 229910052718 tin Inorganic materials 0.000 claims description 3
- 239000011135 tin Substances 0.000 claims description 3
- 150000001805 chlorine compounds Chemical class 0.000 claims 1
- 239000011859 microparticle Substances 0.000 claims 1
- 239000011368 organic material Substances 0.000 claims 1
- 230000021962 pH elevation Effects 0.000 claims 1
- 239000013049 sediment Substances 0.000 claims 1
- 229920002472 Starch Polymers 0.000 description 27
- 235000019698 starch Nutrition 0.000 description 27
- 239000008107 starch Substances 0.000 description 27
- 230000002829 reductive effect Effects 0.000 description 10
- 239000011790 ferrous sulphate Substances 0.000 description 8
- 235000003891 ferrous sulphate Nutrition 0.000 description 8
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 8
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 6
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 6
- 239000011133 lead Substances 0.000 description 6
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 5
- 239000000920 calcium hydroxide Substances 0.000 description 5
- 235000011116 calcium hydroxide Nutrition 0.000 description 5
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 5
- 229910052804 chromium Inorganic materials 0.000 description 5
- 239000011651 chromium Substances 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 150000002500 ions Chemical class 0.000 description 5
- 230000007423 decrease Effects 0.000 description 4
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 4
- 229910021645 metal ion Inorganic materials 0.000 description 4
- 238000006722 reduction reaction Methods 0.000 description 4
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical group [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 description 3
- 239000003638 chemical reducing agent Substances 0.000 description 3
- ORTQZVOHEJQUHG-UHFFFAOYSA-L copper(II) chloride Chemical compound Cl[Cu]Cl ORTQZVOHEJQUHG-UHFFFAOYSA-L 0.000 description 3
- 230000007935 neutral effect Effects 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 2
- 229910021586 Nickel(II) chloride Inorganic materials 0.000 description 2
- 150000001450 anions Chemical class 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- GVPFVAHMJGGAJG-UHFFFAOYSA-L cobalt dichloride Chemical compound [Cl-].[Cl-].[Co+2] GVPFVAHMJGGAJG-UHFFFAOYSA-L 0.000 description 2
- 239000012141 concentrate Substances 0.000 description 2
- FDWREHZXQUYJFJ-UHFFFAOYSA-M gold monochloride Chemical compound [Cl-].[Au+] FDWREHZXQUYJFJ-UHFFFAOYSA-M 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 2
- 229910021506 iron(II) hydroxide Inorganic materials 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
- 239000011572 manganese Substances 0.000 description 2
- 239000002923 metal particle Substances 0.000 description 2
- QMMRZOWCJAIUJA-UHFFFAOYSA-L nickel dichloride Chemical compound Cl[Ni]Cl QMMRZOWCJAIUJA-UHFFFAOYSA-L 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 150000004045 organic chlorine compounds Chemical class 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- CQLFBEKRDQMJLZ-UHFFFAOYSA-M silver acetate Chemical compound [Ag+].CC([O-])=O CQLFBEKRDQMJLZ-UHFFFAOYSA-M 0.000 description 2
- 229940071536 silver acetate Drugs 0.000 description 2
- JPVYNHNXODAKFH-UHFFFAOYSA-N Cu2+ Chemical compound [Cu+2] JPVYNHNXODAKFH-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 229910001431 copper ion Inorganic materials 0.000 description 1
- 239000010840 domestic wastewater Substances 0.000 description 1
- 229960002089 ferrous chloride Drugs 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 150000002505 iron Chemical class 0.000 description 1
- NMCUIPGRVMDVDB-UHFFFAOYSA-L iron dichloride Chemical compound Cl[Fe]Cl NMCUIPGRVMDVDB-UHFFFAOYSA-L 0.000 description 1
- RUTXIHLAWFEWGM-UHFFFAOYSA-H iron(3+) sulfate Chemical compound [Fe+3].[Fe+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O RUTXIHLAWFEWGM-UHFFFAOYSA-H 0.000 description 1
- 229910000360 iron(III) sulfate Inorganic materials 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 150000004692 metal hydroxides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000012266 salt solution Substances 0.000 description 1
- 239000013535 sea water Substances 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000006557 surface reaction Methods 0.000 description 1
- 239000002352 surface water Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
- 239000003643 water by type Substances 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
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Description
本発明は、排水等に含まれる重金属類の除去効果と経済性に優れた水質浄化材に関する。より詳しくは、本発明は、常温で使用することができ、排水等に含まれる重金属類を効果的に除去する経済性に優れた水質浄化材とその製造方法に関する。 The present invention relates to a water purification material excellent in the removal effect and economical efficiency of heavy metals contained in waste water and the like. More specifically, the present invention relates to a water purification material excellent in economy that can be used at room temperature and effectively removes heavy metals contained in waste water and the like, and a method for producing the same.
排水中の重金属を除去する手段として、従来よく知られている方法は、排水に鉄化合物を加えて水酸化鉄沈澱を生成させ、この水酸化鉄沈澱に排水の重金属を取り込ませて澱物化する共沈法である。この方法は、５価ヒ素などについては有効であるが、６価クロム、６価セレン、３価ヒ素などについては除去効果がなく、また、澱物の脱水性が悪いために澱物処理の負担が大きいと云う問題がある。 As a means for removing heavy metals in wastewater, a well-known method is to add an iron compound to wastewater to form an iron hydroxide precipitate, and then take the heavy metal in the wastewater into the iron hydroxide precipitate to form a starch. It is a coprecipitation method. This method is effective for pentavalent arsenic, etc., but hexavalent chromium, hexavalent selenium, trivalent arsenic and the like are not effective for removal, and the starch is not dehydrated, so the burden of starch treatment is low. There is a problem that is large.
一方、排水に還元剤を添加して上記重金属イオンを還元し、排水から除去する方法も知られており、還元剤として鉄粉などが用いられている。例えば、カラム状の槽内に鉄粒子を充填した層を形成し、この鉄粒子充填層に排水を通液して鉄粒子の表面に重金属を吸着させて除去する方法が知られている（特許文献１：特開平９−２６２５９２号公報）。 On the other hand, a method of adding a reducing agent to waste water to reduce the heavy metal ions and removing it from the waste water is also known, and iron powder or the like is used as the reducing agent. For example, a method is known in which a layer filled with iron particles is formed in a column-shaped tank, and drainage is passed through the iron particle packed bed to adsorb and remove heavy metals on the surface of the iron particles (patent) Literature 1: JP-A-9-262592).
しかし、還元剤として鉄粉を用いる方法は、鉄粉表面に重金属が吸着すると表面反応が妨げられて急激に還元力が低下するため、短期間に鉄粉を入れ替える必要があり、メンテナンスの負担が大きいと云う問題がある。さらに、特に酸性条件下では水素ガスや２価鉄が発生するため後処理が必要となる。また、鉄粉を多量に用いるために充填層が格段に重くなり、装置構造の負担も大きい。
本発明は、従来の排水処理方法における上記問題を解決したものであり、沈澱が圧密化され、固液分離性が良く、かつ常温でフェライト処理が可能な経済性および処理効果に優れた水質浄化材とその製造方法を提供する。 The present invention solves the above-mentioned problems in the conventional wastewater treatment method, and is a water purification that is excellent in economic efficiency and treatment effect in which precipitation is consolidated, solid-liquid separation is good, and ferrite treatment is possible at room temperature. A material and a manufacturing method thereof are provided.
本発明は以下の構成からなる水質浄化材に関する。
（１）グリーンラストと共に鉄フェライト、または鉄フェライトおよび還元性鉄水酸化物を含有し、グリーンラストを主体とする還元性の鉄系沈澱物からなり、鉄フェライトはグリーンラストが緩慢に酸化されたものであってマグネタイトを主体とし、該鉄系沈殿物の全鉄に対する２価鉄の比〔Ｆｅ2+／全Ｆｅ〕が０.３以上であることを特徴とする還元性水質浄化材。
（２）鉄系沈殿物の全鉄に対する２価鉄の比〔Ｆｅ2+／全Ｆｅ〕が０.４〜０.６５であることを特徴とする上記(１)に記載する還元性水質浄化材。
（３）グリーンラストと共に鉄フェライト、または鉄フェライトおよび還元性鉄水酸化物を含み、さらに貴金属を含有する還元性の鉄系沈澱物からなる上記(１)または上記(２)に記載する還元性水質浄化材。
（４）上記(３)の還元性水質浄化材において、貴金属として金、銀、銅、ニッケル、コバルトの１種または２種以上を含有する還元性水質浄化材。
（５）上記(１)〜上記(４)の何れかに記載する還元性鉄系沈澱物を水に分散したスラリーであって、その酸化還元電位がＡｇ/ＡｇＣｌ電極基準として−５００ｍＶ〜−８００ｍＶであり、スラリーのｐＨが７〜１１である還元性水質浄化材。
（６）排水等に含まれるセレン、銅、六価クロム、モリブデン、ホウ素、アンチモン、鉛、ヒ素、亜鉛、カドミウム、ニッケル、マンガン、フッ素、スズ、燐、コバルト等の重金属類、またはトリクロロエチレンやジクロロエチレンなどの有機塩素化合物の何れか１種または２種以上の除去に用いられる上記(１)〜上記(５)の何れかに記載する還元性水質浄化材。
The present invention relates to a water purification material having the following configuration.
(1) Containing iron ferrite, or iron ferrite and reducing iron hydroxide, together with green rust, consisting of a reducible iron-based precipitate mainly composed of green rust. A reducing water purification material comprising magnetite as a main component, wherein the ratio of divalent iron to total iron in the iron-based precipitate [Fe 2+ / total Fe] is 0.3 or more.
(2) Reductive water purification according to (1) above, wherein the ratio of divalent iron to total iron in the iron-based precipitate is [Fe 2+ / total Fe] of 0.4 to 0.65. Wood.
(3) Reducing property as described in (1) or (2) above, comprising iron ferrite, or iron ferrite and reducing iron hydroxide together with green last, and further comprising a reducing iron-based precipitate containing a noble metal. Water purification material.
(4) The reducing water purification material according to (3) above, which contains one or more of gold, silver, copper, nickel and cobalt as a noble metal.
(5) A slurry in which the reducing iron-based precipitate described in any one of (1) to (4) above is dispersed in water, and the oxidation-reduction potential is −500 mV to −800 mV based on the Ag / AgCl electrode standard. A reducing water purification material having a slurry pH of 7 to 11.
(6) Selenium, copper, hexavalent chromium, molybdenum, boron, antimony, lead, arsenic, zinc, cadmium, nickel, manganese, fluorine, tin, phosphorus, cobalt, and other heavy metals, or trichlorethylene and dichloroethylene The reducing water purification material as described in any one of (1) to (5) above, which is used for removing any one or two or more of organic chlorine compounds.
本発明は以下の構成からなる水質浄化材の製造方法に関する。
（７）（イ）密閉混合槽において第一鉄塩含有水溶液（処理対象である重金属含有水に第一鉄化合物を添加したものを除く）にアルカリを添加して、ｐＨ８〜１１の液性下でアルカリ液性下で還元性鉄系沈澱物を生成させ、（ロ）この沈澱物スラリーを固液分離し、（ハ）分離した沈殿物をｐＨ１１〜１３の強アルカリ性に調整し、（ニ）この強アルカリ性沈澱物を上記密閉混合槽に戻し、第一鉄塩含有水溶液と混合してグリーンラストを主体とする沈澱物を生成させ、（ホ）沈殿物スラリーを密閉混合槽から抜き出し、固液分離して強アルカリ性化を経て再び密閉混合槽に戻す循環系の何れかの過程において、沈殿物スラリーと空気との接触面積を調整して鉄化合物の酸化を制御し、（ヘ）上記(ロ)から上記(ホ)の工程を繰り返すことによって、
グリーンラストと共に鉄フェライト、または鉄フェライトおよび還元性鉄水酸化物を含有し、グリーンラストを主体とする還元性の鉄系沈澱物からなり、鉄フェライトはグリーンラストが緩慢に酸化されたものであってマグネタイトを主体とし、該鉄系沈殿物の全鉄に対する２価鉄の比〔Ｆｅ 2+ ／全Ｆｅ〕が０.３以上であることを特徴とする還元性水質浄化材を製造する方法。
（８）上記(７)の製造方法において、水に分散したスラリーの酸化還元電位(Ag/AgCl電極基準)が−５００ｍＶ〜−８００ｍＶである、グリーンラストを主体とする還元性鉄系沈澱物からなる還元性水質浄化材を製造する方法。
（９）（イ）水を不活性ガスで曝気して液中の酸素を除去し、（ロ）上記水に第一鉄塩と第二鉄塩を添加して、Ｆｅ2+／Ｆｅ3+＝２（モル比）の割合でＦｅ2+とＦｅ3+を含む水溶液にし、（ハ）この水溶液にアルカリを加え、水酸化物イオン／全Ｆｅ＝２（モル比）に調整し、（ニ）上記(イ)〜(ハ)の工程を密閉混合槽を用いた非酸化性雰囲気下で行い、（ホ）生成した沈澱物を密閉混合槽から抜き出して固液分離し、（ヘ）分離した沈殿物にアルカリを加えてｐＨ１１〜１３の強アルカリ性に調整し、（ト）この強アルカリ性沈澱物を密閉混合槽に戻して上記(ロ)の第一鉄塩水溶液に加え、非酸化性雰囲気下およびｐＨ８〜１１の液性下で沈殿物を生成させ、上記(ホ)〜(ト)の工程を空気界面との接触面積を調整しながら繰り返すことによって、
グリーンラストと共に鉄フェライト、または鉄フェライトおよび還元性鉄水酸化物を含有し、グリーンラストを主体とする還元性の鉄系沈澱物からなり、鉄フェライトはグリーンラストが緩慢に酸化されたものであってマグネタイトを主体とし、該鉄系沈殿物の全鉄に対する２価鉄の比〔Ｆｅ 2+ ／全Ｆｅ〕が０.３以上であって、水に分散したスラリーの酸化還元電位(Ag/AgCl電極基準)が−５００ｍＶ〜−８００ｍＶである還元性水質浄化材を製造する方法。
（１０）上記(７)〜上記(９)の何れかの製造方法において、密閉混合槽に、または密閉混合槽から抜き出した沈殿物スラリーないし沈殿物に、密閉雰囲気下で、貴金属塩類または貴金属微粒子を添加することによって、貴金属を含有し、グリーンラストを主体とする還元性鉄系沈澱物からなる還元性水質浄化材を製造する方法。
The present invention relates to a method for producing a water purification material having the following configuration.
(7) (I) Adding alkali to a ferrous salt-containing aqueous solution (except for a ferrous metal-containing water to be treated and adding a ferrous compound ) in a closed mixing tank, and having a pH of 8-11 in to produce a reducing iron-based precipitate in alkaline solution resistance under (ii) the precipitate slurry was solid-liquid separation, adjusting the precipitate separated (c) a strongly alkaline PH11～13, (d) This strong alkaline precipitate is returned to the above-mentioned closed mixing tank, mixed with a ferrous salt-containing aqueous solution to form a precipitate mainly composed of green last, and (e) the precipitate slurry is extracted from the closed mixing tank, In any process of the circulation system that is separated and made strong alkalinized and returned to the closed mixing tank again, the contact area between the precipitate slurry and air is adjusted to control the oxidation of the iron compound. ) To (e) above are repeated. Te,
It contains iron ferrite, or iron ferrite and reducing iron hydroxide together with green last, and consists of reducing iron-based precipitates mainly composed of green last. Iron ferrite is a product of slow oxidation of green last. And a ratio of divalent iron to total iron in the iron-based precipitate [Fe 2+ / total Fe] is 0.3 or more.
(8) In the production method of (7) above, from a reductive iron-based precipitate mainly composed of green last, wherein the redox potential (Ag / AgCl electrode reference) of the slurry dispersed in water is -500 mV to -800 mV. A method for producing a reducing water purification material.
(9) (a) Aeration of water with an inert gas to remove oxygen in the liquid, (b) Add ferrous salt and ferric salt to the water, and Fe 2+ / Fe 3+ = 2 (molar ratio) to an aqueous solution containing Fe 2+ and Fe 3+ , (c) alkali is added to the aqueous solution, and adjusted to hydroxide ions / total Fe = 2 (molar ratio). ) The above steps (a) to (c) are performed in a non-oxidizing atmosphere using a closed mixing tank, and (e) the generated precipitate is taken out of the closed mixing tank and separated into solid and liquid, and (f) separated. Add alkali to the precipitate to adjust to strong alkalinity of pH 11-13, and (g) return the strong alkaline precipitate to the closed mixing tank and add to the ferrous salt aqueous solution of (b) above, in a non-oxidizing atmosphere. And precipitates are formed under pH 8-11, and the above steps (e) to (g) are repeated while adjusting the contact area with the air interface. ,
It contains iron ferrite, or iron ferrite and reducing iron hydroxide together with green last, and consists of reducing iron-based precipitates mainly composed of green last. Iron ferrite is a product of slow oxidation of green last. The ratio of divalent iron to total iron in the iron-based precipitate is [Fe 2+ / total Fe] of 0.3 or more , and the oxidation-reduction potential (Ag / AgCl) of the slurry dispersed in water. A method for producing a reducing water purification material having an electrode reference) of −500 mV to −800 mV.
(10) In the manufacturing method according to any one of (7) to (9) above, a noble metal salt or noble metal fine particles in a closed mixing tank or a precipitate slurry or a precipitate extracted from the closed mixing tank in a closed atmosphere A method for producing a reducible water purification material comprising a reducible iron-based precipitate containing a precious metal and mainly comprising green last by adding
〔具体的な説明〕
本発明の水質浄化材は、グリーンラストと共に鉄フェライト、または鉄フェライトおよび還元性鉄水酸化物を含有し、グリーンラストを主体とする還元性の鉄系沈澱物からなり、鉄フェライトはグリーンラストが緩慢に酸化されたものであってマグネタイトを主体とし、該鉄系沈殿物の全鉄に対する２価鉄の比〔Ｆｅ 2+ ／全Ｆｅ〕が０.３以上であることを特徴とする還元性水質浄化材である。
[Specific description]
The water purification material of the present invention contains iron ferrite, or iron ferrite and reducing iron hydroxide together with green rust, and consists of a reducing iron-based precipitate mainly composed of green rust. Reducing property characterized by being slowly oxidized, mainly composed of magnetite, and the ratio of divalent iron to total iron in the iron-based precipitate [Fe 2+ / total Fe] is 0.3 or more Water purification material.
グリーンラストは、第一鉄と第二鉄の水酸化物が層状をなす青緑色の物質であり、層間にアニオンを取り込んだ構造を有し、例えば次式（１）によって表される。
〔ＦｅII (6-x)ＦｅIII x（ＯＨ）12〕x+〔Ａx/n・ｙＨ2Ｏ〕x- …（１）
（０.９＜ｘ＜４.２、Ｆｅ2+/全Ｆｅ＝０.３〜０.８５）
（Ａ：アニオン、ＳＯ4 2-、Ｃｌ-など）
例えば、Ａ＝ＳＯ4 2-、ｘ＝２のとき、グリーンラスト(II)〔ＧＲ(II)〕と呼ばれる。グリーンラストは緩慢に酸化することによって鉄フェライト化する。
Green last is a blue-green substance in which a hydroxide of ferrous iron and ferric iron forms a layer, and has a structure in which an anion is taken in between layers, and is represented by, for example, the following formula (1).
[Fe II (6-x) Fe III x (OH) 12 ] x + [A x / n · yH 2 O] x- ... (1)
(0.9 <x <4.2, Fe 2+ / total Fe = 0.3 to 0.85)
(A: anion, SO 4 2− , Cl −, etc.)
For example, when A = SO 4 2− and x = 2, it is called green last (II) [GR (II)]. Green rust becomes iron ferrite by slowly oxidizing.
鉄フェライトは、マグネタイト（ＦｅIIＯＦｅIII 2Ｏ3）を主体とするが、一部にＦｅ(II)またはＦｅ(III)が重金属と置換したものでもよい。本発明の還元性を有する鉄系沈澱物は、例えば、排水等に含まれる重金属イオンがグリーンラストに取り込まれ、重金属を一部に含んだ状態で鉄フェライト化したものを用いることができる。 The iron ferrite is mainly composed of magnetite (Fe II OFe III 2 O 3 ), but may be partially substituted with heavy metal by Fe (II) or Fe (III). As the iron-based precipitate having reducibility according to the present invention, for example, a ferritic iron precipitate in a state in which heavy metal ions contained in waste water and the like are taken into the green last and partially containing heavy metals can be used.
還元性鉄水酸化物は、２価鉄の水酸化鉄(II)を主体とする沈澱であり、例えば、第一鉄塩溶液に非酸化性雰囲気下でアルカリを加えて沈澱を生成させることによって得ることができる。この水酸化鉄(II)は中性もしくはアルカリ性下で緩慢に酸化することによって次第にグリーンラストに変質する。 The reducing iron hydroxide is a precipitate mainly composed of iron (II) hydroxide of divalent iron. For example, by adding an alkali to a ferrous salt solution in a non-oxidizing atmosphere to form a precipitate. Obtainable. This iron (II) hydroxide gradually changes to green last by slowly oxidizing under neutral or alkaline conditions.
本発明の鉄系沈澱物は、還元力を有するように、該沈澱中の全鉄に対する２価鉄の比〔Ｆｅ2+／全Ｆｅ〕が少なくとも０.３以上のものが用いられる。鉄系沈澱物の２価鉄の比がこれより小さいと還元力が弱いので適当ではない。因みに、上記のとおり、グリーンラストまたはグリーンラストと鉄フェライトとの混合物では、上記２価鉄の比〔Ｆｅ2+／全Ｆｅ〕は０.３〜０.８５であり、２価鉄量の多いものほど還元力が強い。なお、グリーンラストは緩慢に酸化することによって鉄フェライト化するので、通常は、上記２価鉄の比は０.４〜０.６５、好ましくは０.５〜０.６であればよい。 As the iron-based precipitate of the present invention, one having a ratio [Fe 2+ / total Fe] of divalent iron to total iron in the precipitate of at least 0.3 or more is used so as to have a reducing power. If the ratio of divalent iron in the iron-based precipitate is smaller than this, the reducing power is weak, which is not suitable. Incidentally, as described above, in the green last or a mixture of green last and iron ferrite, the ratio of the divalent iron [Fe 2+ / total Fe] is 0.3 to 0.85, and the amount of divalent iron is large. The stronger the reduction, the stronger. In addition, since green last is iron-ferrite by being oxidized slowly, the ratio of the divalent iron is usually 0.4 to 0.65, preferably 0.5 to 0.6.
本発明の水質浄化材は上記鉄系沈澱物からなる。この沈澱物を水に分散したスラリーの酸化還元電位は、Ａｇ/ＡｇＣｌ電極基準として−５００ｍＶ〜−８００ｍＶが好ましく、−６２０ｍＶ〜−６８０ｍＶがさらに好ましい。また、スラリーのｐＨは７〜１１が好ましく、ｐＨ９〜１０がさらに好ましい。酸化還元電位が上記範囲より高いと還元能力が落ちるため重金属類の除去効果が低下する。また、ｐＨが上記範囲より低いと２価鉄イオンが溶出して水質が悪化する。一方、ｐＨが上記範囲よりも高いと還元能力が落ちる。 The water purification material of the present invention comprises the above iron-based precipitate. The oxidation-reduction potential of the slurry in which the precipitate is dispersed in water is preferably −500 mV to −800 mV, more preferably −620 mV to −680 mV, based on the Ag / AgCl electrode. The pH of the slurry is preferably 7 to 11, and more preferably 9 to 10. If the oxidation-reduction potential is higher than the above range, the reducing ability is lowered, and the effect of removing heavy metals is lowered. Moreover, when pH is lower than the said range, divalent iron ion will elute and water quality will deteriorate. On the other hand, when the pH is higher than the above range, the reducing ability decreases.
本発明の水質浄化材は、グリーンラストと共に、鉄フェライトおよび鉄水酸化物の少なくとも何れかを含み、さらに貴金属粒子を含有する還元性の鉄系沈澱物を用いることができる。含有する貴金属としては、金、銀、銅、ニッケル、コバルトの１種または２種以上を用いることができる。 The water purification material of the present invention can use a reducing iron-based precipitate that contains at least one of iron ferrite and iron hydroxide, and further contains noble metal particles, together with green last. As a noble metal to be contained, one or more of gold, silver, copper, nickel, and cobalt can be used.
上記鉄系沈殿物が上記貴金属粒子を含有することによって、貴金属による触媒作用が加わり、水質浄化能力が大幅に向上する。具体的には、例えば、六価セレンを含む排水等を本発明の水質浄化材を接触させて、セレンを除去する場合、銅微粒子を含有した水質浄化材は、これを含有しないものに比べて、反応速度が１４０倍程度向上する。金、銀、ニッケル、コバルトを含有させた場合も同様の効果が得られる。 When the iron-based precipitate contains the noble metal particles, the catalytic action of the noble metal is added and the water purification ability is greatly improved. Specifically, for example, when removing selenium by contacting wastewater containing hexavalent selenium with the water purification material of the present invention and removing selenium, the water purification material containing copper fine particles is in comparison with those not containing this. The reaction rate is improved by about 140 times. The same effect can be obtained when gold, silver, nickel, or cobalt is contained.
上記鉄系沈殿物に貴金属を含有させるには、この鉄系沈殿物を生成させる際に、密閉混合槽で生成した鉄系沈澱物スラリー、または、密閉混合槽から抜き出した鉄系沈殿物スラリー、あるいは固液分離した鉄系沈殿物に、貴金属塩類または貴金属微粒子を添加すれば良い。これらの貴金属塩類または貴金属微粒子は、鉄系沈殿物の酸化を避けるため、密閉して空気の侵入を防止した非酸化性雰囲気下で添加するのが好ましい。 In order to contain the noble metal in the iron-based precipitate, when generating the iron-based precipitate, the iron-based precipitate slurry generated in the closed mixing tank, or the iron-based precipitate slurry extracted from the closed mixing tank, Alternatively, noble metal salts or noble metal fine particles may be added to the solid-liquid separated iron-based precipitate. These precious metal salts or precious metal fine particles are preferably added in a non-oxidizing atmosphere that is sealed and prevented from entering air in order to avoid oxidation of the iron-based precipitate.
貴金属塩類としては、塩化銅、塩化金、酢酸銀、塩化ニッケル、塩化コバルトなどを用いることができる。これらの貴金属塩類は非酸化性雰囲気下でイオン化し、沈殿物中に貴金属が析出する。 As the noble metal salts, copper chloride, gold chloride, silver acetate, nickel chloride, cobalt chloride and the like can be used. These noble metal salts are ionized in a non-oxidizing atmosphere, and the noble metal is deposited in the precipitate.
本発明の水質浄化材は次のようにして製造することができる。
（イ）密閉混合槽において、第一鉄塩含有水溶液にアルカリを添加して、アルカリ液性下で還元性鉄系沈澱物を生成させる。
（ロ）この沈澱物スラリーを固液分離する。
（ハ）分離した沈殿物にアルカリを添加して強アルカリ性に調整する。
（ニ）この強アルカリ性沈澱物を上記密閉混合槽に戻し、第一鉄塩含有水溶液と混合してグリーンラストを主体とする沈澱物を生成させる。
（ホ）沈殿物スラリーを密閉混合槽から抜き出し、固液分離して強アルカリ性化を経て密閉混合槽に戻す循環系の何れかの過程において沈殿物スラリーと空気との接触面積を調整して鉄化合物の酸化を制御する。
（ヘ）上記(ロ)から上記(ホ)の工程を繰り返して、鉄系沈殿物を濃縮する。
The water purification material of the present invention can be produced as follows.
(A) In a closed mixing tank, an alkali is added to the ferrous salt-containing aqueous solution to produce a reducible iron-based precipitate under alkaline liquidity.
(B) The precipitate slurry is subjected to solid-liquid separation.
(C) Add alkali to the separated precipitate to adjust to strong alkalinity.
(D) This strong alkaline precipitate is returned to the above-mentioned closed mixing tank and mixed with a ferrous salt-containing aqueous solution to form a precipitate mainly composed of green last.
(E) The precipitate slurry is withdrawn from the closed mixing tank, solid-liquid separated, made strong alkalinized and returned to the closed mixing tank, and the contact area between the precipitate slurry and air is adjusted to adjust the contact area between the iron and the iron. Controls oxidation of compounds.
(F) The steps (b) to (e) are repeated to concentrate the iron-based precipitate.
上記(イ)の工程において、例えば、第一鉄塩含有水溶液に水酸化カルシウム水溶液を添加して、密閉混合槽のｐＨを８〜１１、好ましくはｐＨ９.５〜１０.５に調整する。また、上記(ハ)の工程において、沈殿物に水酸化カルシウム水溶液を加えて、沈殿物をｐＨ１１〜１３の強アルカリ性に調整する。さらに、上記(ホ)の工程において、沈殿物スラリーと空気との接触面積を調整するには、例えば、分離した沈殿物にアルカリを添加する際に、開放型の槽を用い、このアルカリ添加槽の開口面積を調整すれば良い。 In the step (a), for example, an aqueous calcium hydroxide solution is added to the ferrous salt-containing aqueous solution to adjust the pH of the closed mixing tank to 8 to 11, preferably pH 9.5 to 10.5. In the step (c), a calcium hydroxide aqueous solution is added to the precipitate to adjust the precipitate to a strong alkalinity of pH 11-13. Further, in the step (e), in order to adjust the contact area between the precipitate slurry and air, for example, when adding alkali to the separated precipitate, an open tank is used, and this alkali addition tank What is necessary is just to adjust the opening area.
なお、密閉混合槽に代えて開放型の混合槽を用いた全体が開放型の反応系や、あるいは密閉型のアルカリ添加槽を用いた全体が空気との接触のない密閉型の反応系では、何れもグリーンラストを主体とする還元性鉄系沈殿物が十分に生成しないので、本発明の水質浄化材を得ることができない。 In addition, instead of the closed mixing tank, the whole using an open type mixing tank is an open type reaction system, or the whole using a sealed type alkali addition tank is a closed type reaction system without contact with air, In any case, since the reducing iron-based precipitate mainly composed of green rust is not sufficiently generated, the water purification material of the present invention cannot be obtained.
また、本発明の水質浄化材は次のように、２価鉄と３価鉄を含む水溶液を用いて製造することができる。
（イ）水（イオン交換水等）を不活性ガス（99.99％Ｎ2）で曝気して液中の酸素を除去する。
（ロ）上記水に、第一鉄塩（FeSO4・7H2O等）と第二鉄塩（Fe2(SO4)3等）を添加して、Ｆｅ2+／Ｆｅ3+＝２（モル比）の割合でＦｅ2+とＦｅ3+を含む水溶液にする。
（ハ）この水溶液にアルカリ(消石灰等)を加え、水酸化物イオン／全Ｆｅ＝２(モル比)に調整する。この結果、以下の反応式に示すようにグリーンラスト(II)が生成する。
４Ｆｅ2+＋２Ｆｅ3+＋１２ＯＨ-＋ＳＯ4 2- → Ｆｅ4Ｆｅ2(ＯＨ)12ＳＯ4
（ニ）上記(イ)〜(ハ)の工程を密閉混合槽を用いた非酸化性雰囲気下、例えば不活性ガス雰囲気下（99.99％Ｎ2等）で行う。
（ホ）生成した沈澱物スラリーを密閉混合槽から抜き出し、固液分離する。
（ヘ）分離した沈殿物にアルカリ(消石灰等)を加えてｐＨ１１〜１３の強アルカリ性に調整する。
（ト）この強アルカリ性沈澱物を密閉混合槽に戻して上記(ロ)の第一鉄塩水溶液に加え、非酸化性雰囲気下およびｐＨ８〜１１の液性下で沈殿物を生成させる。
（チ）上記(ホ)〜(ト)の工程を空気界面との接触面積を調整しながら繰り返して、鉄系沈殿物を濃縮する。
Moreover, the water purification material of this invention can be manufactured using the aqueous solution containing bivalent iron and trivalent iron as follows.
(A) Aeration of water (ion exchange water or the like) with an inert gas (99.99% N 2 ) to remove oxygen in the liquid.
(B) A ferrous salt (FeSO 4 .7H 2 O, etc.) and a ferric salt (Fe 2 (SO 4 ) 3 etc.) are added to the water, and Fe 2+ / Fe 3+ = 2 ( An aqueous solution containing Fe 2+ and Fe 3+ at a molar ratio).
(C) An alkali (slaked lime or the like) is added to this aqueous solution to adjust to hydroxide ions / total Fe = 2 (molar ratio). As a result, green last (II) is produced as shown in the following reaction formula.
4Fe 2+ + 2Fe 3+ + 12OH − + SO 4 2− → Fe 4 Fe 2 (OH) 12 SO 4
(D) The above steps (a) to (c) are performed in a non-oxidizing atmosphere using a closed mixing tank, for example, in an inert gas atmosphere (99.99% N 2 or the like).
(E) The produced precipitate slurry is extracted from the closed mixing tank and solid-liquid separated.
(F) An alkali (slaked lime or the like) is added to the separated precipitate to adjust the pH to 11-13.
(G) Return this strong alkaline precipitate to the closed mixing tank and add it to the ferrous salt aqueous solution of (b) above to produce a precipitate under a non-oxidizing atmosphere and a liquidity of pH 8-11.
(H) The steps (e) to (g) are repeated while adjusting the contact area with the air interface to concentrate the iron-based precipitate.
上記各製造方法によって、全鉄に対する二価鉄の比(Ｆｅ2+／全Ｆｅ)０.３以上であって酸化還元電位(Ag/AgCl電極基準)−５００ｍＶ〜−８００ｍＶ、好ましくは、全鉄に対する二価鉄の比(Ｆｅ2+／全Ｆｅ)０.４〜０.６５であって酸化還元電位(Ag/AgCl電極基準)−６２０ｍＶ〜−６８０ｍＶの、グリーンラストを主体とする還元性鉄系沈澱物からなる還元性水質浄化材を製造することができる。 According to each of the above production methods, the ratio of divalent iron to total iron (Fe 2+ / total Fe) is 0.3 or more and the oxidation-reduction potential (Ag / AgCl electrode standard) is −500 mV to −800 mV, preferably Ratio of divalent iron to Fe (Fe 2+ / total Fe) of 0.4 to 0.65 and redox potential (Ag / AgCl electrode standard) of -620 mV to -680 mV based on green last A reducible water purification material comprising a system precipitate can be produced.
上記製造方法において、鉄系沈殿物に貴金属を含有させるには、例えば、沈殿物スラリーが生成した密閉混合槽に、貴金属塩類または貴金属微粒子を添加すれば良い。この場合、ｐＨが高すぎると貴金属の水酸化物が生成するので、密閉混合槽において、沈殿物スラリーの生成が進行して槽内のｐＨがやや低下した段階（ｐＨ８前後）で、貴金属塩類または貴金属微粒子を添加するのが良い。また、貴金属塩類または貴金属微粒子の添加量は、貴金属イオン量が沈殿物スラリー１リットル当たり０.５〜１０mgとなる量であれば良い。 In the above production method, in order to contain the noble metal in the iron-based precipitate, for example, a noble metal salt or noble metal fine particles may be added to the closed mixing tank in which the precipitate slurry is generated. In this case, since noble metal hydroxide is produced when the pH is too high, in the closed mixing tank, the formation of the precipitate slurry proceeds and the pH in the tank is slightly lowered (around pH 8). It is better to add noble metal fine particles. Moreover, the addition amount of the noble metal salts or the noble metal fine particles may be an amount such that the noble metal ion amount is 0.5 to 10 mg per liter of the precipitate slurry.
本発明の水質浄化材は、ｐＨ７〜１１の中性もしくはアルカリ性で使用するのが好ましく、ｐＨ９〜１０がさらに好ましい。本発明の水質浄化材を用いる場合、使用温度は制限されない。常温でも使用することができる。 The water purification material of the present invention is preferably used at a neutral or alkaline pH of 7 to 11, and more preferably a pH of 9 to 10. When the water purification material of the present invention is used, the use temperature is not limited. Can be used at room temperature.
本発明の水質浄化材と排水を中性もしくはアルカリ性下で十分に接触させる。接触の方法としては連続式でも回分式でもよく、装置の形式としては攪拌槽を用いて排水を槽内の澱物と接触させる方法、充填カラムに澱物を充填し排水と接触させる方法、流動床を用いて澱物を流動せしめ排水と接触させる方法等が可能である。必要に応じて、硫酸第一鉄、塩化第一鉄など２価の鉄系塩類を添加する。また、非酸化性雰囲気に調整することによって還元反応をさらに促進することができる。 The water purification material of the present invention and waste water are sufficiently brought into contact under neutral or alkaline conditions. The contact method may be continuous or batch-type, and the type of apparatus is a method in which waste water is brought into contact with starch in the tank using a stirring tank, a method in which a packed column is filled with starch and brought into contact with waste water, and flow. It is possible to use a method in which starch is fluidized using a floor and brought into contact with wastewater. If necessary, divalent iron-based salts such as ferrous sulfate and ferrous chloride are added. Further, the reduction reaction can be further promoted by adjusting to a non-oxidizing atmosphere.
本発明の水質浄化材は、排水等に含まれるセレン、銅、六価クロム、モリブデン、ホウ素、アンチモン、鉛、ヒ素、亜鉛、カドミウム、ニッケル、マンガン、フッ素、スズ、燐、コバルト等の重金属類、またはトリクロロエチレンやジクロロエチレンなどの有機塩素化合物の何れか１種または２種以上の除去に用いることができる。ここで、排水等とは、自然発生的または人為的に生じた各種の廃水や排水、流水等を含み、例えば、工場排水や生活排水、下水、海水、河川水、沼や湖池の水、地表の溜り水、河川等の堰止域の水、地下の流水や溜り水、暗渠の水などを云う。なお、本発明の説明において、これらの水を含めて排水等と云う場合がある。 The water purification material of the present invention includes heavy metals such as selenium, copper, hexavalent chromium, molybdenum, boron, antimony, lead, arsenic, zinc, cadmium, nickel, manganese, fluorine, tin, phosphorus, cobalt, etc. Or any one or more of organic chlorine compounds such as trichlorethylene and dichloroethylene can be used for removal. Here, the drainage includes various types of wastewater, wastewater, running water, etc. that have been generated naturally or artificially, such as factory wastewater, domestic wastewater, sewage, seawater, river water, water of swamps and lakes, This refers to surface water, water in rivers and other dams, underground running water, water, and underwater. In the description of the present invention, these waters are sometimes referred to as drainage.
本発明の水質浄化材を、重金属類を含有する排水等に接触することによって、排水等に含まれる重金属類は上記鉄系沈澱物に取り込まれて澱物化し、排水等から除去される。例えば、カドミウム、鉛、亜鉛、ニッケル、マンガンなどの重金属イオンは鉄と置換して沈澱物に取り込まれる。また６価セレンや６価クロムなどのオキシアニオンは、４価セレンや金属セレン、または３価クロムに還元され、水質浄化材の鉄系沈澱物に取り込まれる。さらに、セレンおよびクロム以外のオキシアニオン、たとえば５価ヒ素、３価ヒ素はいずれもグリーンラストの緩い層状構造に中に取り込まれて排水から除去される。 By bringing the water purification material of the present invention into contact with wastewater containing heavy metals, the heavy metals contained in the wastewater and the like are taken into the iron-based precipitates and become starch, and are removed from the wastewater and the like. For example, heavy metal ions such as cadmium, lead, zinc, nickel, and manganese are substituted for iron and incorporated into the precipitate. Further, oxyanions such as hexavalent selenium and hexavalent chromium are reduced to tetravalent selenium, metal selenium, or trivalent chromium, and are taken into the iron-based precipitate of the water purification material. Further, oxyanions other than selenium and chromium, for example pentavalent arsenic and trivalent arsenic, are all taken into the loose layered structure of green last and removed from the waste water.
本発明の水質浄化材を用いる場合、セレン、クロム、トリクロロエチレン、ジクロロエチレンのように還元反応によって除去される物質が排水等に含まれる場合は、水質浄化剤と排水等を非酸化性雰囲気下で接触させることが好ましい。カドミウム、鉛、亜鉛、ニッケル、ヒ素等については浄化に還元反応を要さないため、水質浄化剤と排水等を開放された混合槽で接触させてもよい。 When the water purification material of the present invention is used, when the substance removed by the reduction reaction such as selenium, chromium, trichloroethylene, dichloroethylene is contained in the wastewater, etc., the water purification agent and the wastewater are contacted in a non-oxidizing atmosphere. It is preferable to make it. Since cadmium, lead, zinc, nickel, arsenic and the like do not require a reduction reaction for purification, the water purification agent and drainage may be contacted in an open mixing tank.
このように、排水を上記水質浄化材に接触することによって、排水中の重金属が上記鉄系沈澱物に取り込まれて排水から除去され、排水が浄化される。該水質浄化材を繰り返し使用し、重金属が溜まって水質浄化材の還元力が低下してきたら、槽内から水質浄化材を取り出して還元力の強い新しい水質浄化材に交換すれば良い。 Thus, by contacting the wastewater with the water purification material, heavy metals in the wastewater are taken into the iron-based precipitate and removed from the wastewater, and the wastewater is purified. When the water purification material is repeatedly used and heavy metals accumulate and the reducing power of the water purification material decreases, the water purification material may be taken out of the tank and replaced with a new water purification material having a strong reducing power.
本発明の水質浄化材は、排水等に含まれる重金属を澱物中に取り込むので、効果的に排水等から除去することができる。具体的には、例えば、セレン、カドミウム、クロム、鉛、亜鉛、銅、ニッケルの排水中の濃度を０.０１mg/L未満に低減することができ、さらに、ヒ素、アンチモンの排水中の濃度を０.００１mg/L未満に低減することができる。また、本発明の水質浄化材を使用する場合には、加熱する必要がなく、常温で排水等の重金属を取り込んで沈澱物の鉄フェライト化が進む。さらに、この鉄フェライト化によって圧密されたコンパクトな澱物が形成されるので脱水性が良く、従って澱物の後処理の負担が少なく、経済性および取扱性に優れる。なお、沈澱物はマグネタイトを主体とするため磁性を帯びており、分離した沈澱を磁石に吸着させて処理することができる。 Since the water purification material of this invention takes in the heavy metal contained in waste_water | drain etc. in a starch, it can remove from waste_water | drain etc. effectively. Specifically, for example, the concentration of selenium, cadmium, chromium, lead, zinc, copper, nickel in wastewater can be reduced to less than 0.01 mg / L, and the concentration of arsenic and antimony in wastewater can be reduced. It can be reduced to less than 0.001 mg / L. In addition, when the water purification material of the present invention is used, it is not necessary to heat it, and heavy metals such as waste water are taken in at room temperature, and the precipitation of iron precipitates proceeds. Further, since compacted compact starch is formed by this iron ferrite formation, the dehydrating property is good, so the burden of post-treatment of the starch is small, and the economy and handling properties are excellent. In addition, since the precipitate is mainly composed of magnetite, it has magnetism and can be treated by adsorbing the separated precipitate to a magnet.
〔実施例１〕
水２Ｌに硫酸第一鉄をＦｅ(II)として６００mg/Lになるように添加して出発液とした。これに消石灰を添加してｐＨ９.０に調整し、沈澱物を生成させた。この沈澱物を固液分離して回収し、さらに消石灰を加えてｐＨ１２前後の強アルカリに調整した。この強アルカリ性澱物を、Ｆｅ(II)として６００mg/Lを含む硫酸第一鉄水溶液に加え、ｐＨ９.０に調整して攪拌しスラリーを調製した。生成した沈澱物を固液分離して濃縮澱物を得た。この澱物を上記硫酸第一鉄水溶液に加えて濃縮澱物を得る操作を、空気界面との接触面積を調整しながら２５回繰り返し、スラリー中の全鉄に対する二価鉄の比（Ｆｅ2+／全Ｆｅ）を０.４〜０.６５に、および酸化還元電位(Ag/AgCl電極基準)を−６２０mV〜−６８０mVにした。この結果、固液濃度１４０ｇ/Lの濃縮澱物スラリー０.３８Ｌを得た。この濃縮澱物に、表１に示す金属イオンを含む模擬排水２.０Ｌを接触させ、密閉混合槽中で２時間攪拌した後に固液分離し、液中の金属イオン濃度を測定した。この結果を表１に示す。
[Example 1]
Ferrous sulfate as Fe (II) was added to 2 L of water at 600 mg / L to obtain a starting solution. Slaked lime was added to this to adjust to pH 9.0, and a precipitate was formed. This precipitate was recovered by solid-liquid separation, and further slaked lime was added to adjust to a strong alkali around pH 12. This strongly alkaline starch was added to a ferrous sulfate aqueous solution containing 600 mg / L as Fe (II), adjusted to pH 9.0, and stirred to prepare a slurry. The formed precipitate was subjected to solid-liquid separation to obtain a concentrated starch. The operation of adding this starch to the ferrous sulfate aqueous solution to obtain a concentrated starch was repeated 25 times while adjusting the contact area with the air interface, and the ratio of divalent iron to total iron in the slurry (Fe 2+ / Total Fe) was 0.4 to 0.65, and the redox potential (Ag / AgCl electrode standard) was -620 mV to -680 mV. As a result, 0.38 L of concentrated starch slurry having a solid-liquid concentration of 140 g / L was obtained. To this concentrated starch, 2.0 L of simulated waste water containing metal ions shown in Table 1 was brought into contact. After stirring in a closed mixing tank for 2 hours, solid-liquid separation was performed, and the metal ion concentration in the liquid was measured. The results are shown in Table 1.
表１に示すように、本発明の水質浄化材によって処理した排水の重金属イオンは大幅に低減されている。具体的には、セレン、カドミウム、クロム、鉛、亜鉛、銅、ニッケルの排水中の濃度は何れも０.０１mg/L未満に低減され、ヒ素、アンチモンの排水中の濃度は０.００１mg/L未満に低減されている。また、モリブデン、ホウ素、マンガン、フッ素の濃度も大幅に低減される。 As shown in Table 1, the heavy metal ions in the wastewater treated with the water purification material of the present invention are greatly reduced. Specifically, the concentrations of selenium, cadmium, chromium, lead, zinc, copper and nickel in the wastewater are all reduced to less than 0.01 mg / L, and the concentrations of arsenic and antimony in the wastewater are 0.001 mg / L. Has been reduced to less than. Also, the concentration of molybdenum, boron, manganese and fluorine is greatly reduced.
〔実施例２〕
不活性雰囲気下で以下の操作を行い澱物を作成した。不活性ガスで曝気した水２Ｌに硫酸第一鉄と硫酸第二鉄を加え、Ｆｅ(II)が４００mg/L・Ｆｅ(III)が２００mg/Lになるようにした。次いで、これにＮａＯＨを加え、水酸化物イオン/全Ｆｅ＝２（モル比）に調整した。その結果生成した沈澱物を固液分離して回収した。
上記工程で作成した澱物を出発物質にして、澱物を硫酸第一鉄水溶液に加えて濃縮澱物を得る操作を繰り返した。まず澱物にＮａＯＨを加えｐＨ１２前後の強アルカリにした。この強アルカリ性澱物をＦｅ(II)として６００mg/Lを含む硫酸第一鉄水溶液に加え、ｐＨ９.０に調整して攪拌し、スラリーを調製した。生成した沈澱物を固液分離して濃縮澱物を得た。この澱物を強アルカリ性にしてから上記硫酸第一鉄水溶液に加えて濃縮澱物を得る操作を空気界面との接触面積を調整しながら２５回繰り返し、スラリー中の全鉄に対する二価鉄の比（Ｆｅ2+／全Ｆｅ）を０.４〜０.６５に、および酸化還元電位(Ag/AgCl電極基準)を−６２０mV〜−６８０mVにした。この結果、固液濃度１４０ｇ/Lの濃縮澱物スラリー０.３８Ｌを得た。この濃縮澱物に、表１に示す金属イオンを含む模擬排水２.０Ｌを接触させ、密閉混合槽中で２時間攪拌した後に固液分離し、液中の金属イオン濃度を測定した。その結果は実施例１と同様であった。
[Example 2]
A starch was prepared by the following operation under an inert atmosphere. Ferrous sulfate and ferric sulfate were added to 2 L of water aerated with an inert gas so that Fe (II) was 400 mg / L · Fe (III) was 200 mg / L. Subsequently, NaOH was added thereto to adjust the hydroxide ion / total Fe = 2 (molar ratio). The resulting precipitate was recovered by solid-liquid separation.
Using the starch prepared in the above step as a starting material, the operation of adding the starch to an aqueous ferrous sulfate solution to obtain a concentrated starch was repeated. First, NaOH was added to the starch to make a strong alkali around pH 12. This strongly alkaline starch was added to a ferrous sulfate aqueous solution containing 600 mg / L as Fe (II), adjusted to pH 9.0, and stirred to prepare a slurry. The formed precipitate was subjected to solid-liquid separation to obtain a concentrated starch. The operation of making this starch strongly alkaline and adding it to the ferrous sulfate aqueous solution to obtain a concentrated starch was repeated 25 times while adjusting the contact area with the air interface, and the ratio of divalent iron to the total iron in the slurry was (Fe 2+ / total Fe) was set to 0.4 to 0.65, and the oxidation-reduction potential (Ag / AgCl electrode standard) was set to −620 mV to −680 mV. As a result, 0.38 L of concentrated starch slurry having a solid-liquid concentration of 140 g / L was obtained. To this concentrated starch, 2.0 L of simulated waste water containing metal ions shown in Table 1 was brought into contact. After stirring in a closed mixing tank for 2 hours, solid-liquid separation was performed, and the metal ion concentration in the liquid was measured. The result was the same as in Example 1.
〔実施例３〕
実施例１と同様にして濃縮沈殿物を得る際に、図１に示す製造工程に従って、密閉混合槽に塩化銅水溶液を、銅イオン量が沈殿物スラリー１Ｌ当たり１mgになるように添加し、銅１０８mg/L、Ｆｅ3+２４０００mg/L、Ｆｅ2+２４０００mg/Lを含む水質浄化材を製造した。密閉混合槽中で、この水質浄化材０.３８Ｌに、六価セレン２mg/Lを含む水２.０Ｌを接触させて、セレンを除去した。この結果を図２に示した。また、銅を含有しない以外は同様の濃縮沈殿物からなる水質浄化材を用い、密閉混合槽中で同様のセレン含有水を接触させてセレンを除去した。この結果を対比して図２に示す。
図２に示すように、銅を含有する水質浄化材は、セレン含有水が接触した直後からセレン濃度が急激に減少し、０.１時間後にはほぼ全量のセレンが除去され、銅を含有しない水質浄化材に比べて反応速度が約１４０倍向上している。
Example 3
When obtaining a concentrated precipitate in the same manner as in Example 1, according to the production process shown in FIG. 1, an aqueous copper chloride solution was added to the closed mixing tank so that the amount of copper ions was 1 mg per liter of the precipitate slurry. A water purification material containing 108 mg / L, Fe 3+ 24000 mg / L, and Fe 2+ 24000 mg / L was produced. In a closed mixing tank, 0.38 L of this water purification material was brought into contact with 2.0 L of water containing 2 mg / L of hexavalent selenium to remove selenium. The results are shown in FIG. Moreover, the same selenium containing water was made to contact in the airtight mixing tank, and the selenium was removed using the water purification material which consists of the same concentrated precipitate except not containing copper. This result is shown in contrast in FIG.
As shown in FIG. 2, in the water purification material containing copper, the selenium concentration sharply decreases immediately after the contact with the selenium-containing water, and almost the entire amount of selenium is removed after 0.1 hour and does not contain copper. The reaction rate is improved by about 140 times compared to the water purification material.
〔実施例４〕
実施例３において、塩化銅に代えて、塩化金、酢酸銀、塩化ニッケル、塩化コバルトを用い、これらの金属を含有する濃縮沈殿物からなる水質浄化材を製造した。この水質浄化材を用い、実施例３と同様にしてセレン含有水からセレンを除去した。この結果を表２に示した。上記金属を含有する水質浄化材は、セレン除去速度が格段に向上している。
Example 4
In Example 3, instead of copper chloride, gold chloride, silver acetate, nickel chloride and cobalt chloride were used to produce a water purification material comprising a concentrated precipitate containing these metals. Using this water purification material, selenium was removed from the selenium-containing water in the same manner as in Example 3. The results are shown in Table 2. The water purification material containing the metal has a markedly improved selenium removal rate.
Claims (10)
グリーンラストと共に鉄フェライト、または鉄フェライトおよび還元性鉄水酸化物を含有し、グリーンラストを主体とする還元性の鉄系沈澱物からなり、鉄フェライトはグリーンラストが緩慢に酸化されたものであってマグネタイトを主体とし、該鉄系沈殿物の全鉄に対する２価鉄の比〔Ｆｅ 2+ ／全Ｆｅ〕が０.３以上であることを特徴とする還元性水質浄化材を製造する方法。 (I) Add alkali to ferrous salt-containing aqueous solution (except for ferrous metal-containing water to be treated, added ferrous compound ) in a closed mixing tank, and alkali solution under pH 8-11 (B) The precipitate slurry is subjected to solid-liquid separation, (c) the separated precipitate is adjusted to have a strong alkalinity of pH 11 to 13 , and (d) the strongly alkaline substance is produced. The precipitate is returned to the above-mentioned closed mixing tank, mixed with the ferrous salt-containing aqueous solution to produce a precipitate mainly composed of green last, and (e) the precipitate slurry is extracted from the closed mixing tank and solid-liquid separated. In any process of the circulation system that returns to the closed mixing tank again through strong alkalinization, the contact area between the precipitate slurry and the air is adjusted to control the oxidation of the iron compound. By repeating step (e),
It contains iron ferrite, or iron ferrite and reducing iron hydroxide together with green last, and consists of reducing iron-based precipitates mainly composed of green last. Iron ferrite is a product of slow oxidation of green last. And a ratio of divalent iron to total iron in the iron-based precipitate [Fe 2+ / total Fe] is 0.3 or more.
グリーンラストと共に鉄フェライト、または鉄フェライトおよび還元性鉄水酸化物を含有し、グリーンラストを主体とする還元性の鉄系沈澱物からなり、鉄フェライトはグリーンラストが緩慢に酸化されたものであってマグネタイトを主体とし、該鉄系沈殿物の全鉄に対する２価鉄の比〔Ｆｅ 2+ ／全Ｆｅ〕が０.３以上であって、水に分散したスラリーの酸化還元電位(Ag/AgCl電極基準)が−５００ｍＶ〜−８００ｍＶである還元性水質浄化材を製造する方法。 (A) Aeration of water with an inert gas to remove oxygen in the liquid, (b) Add ferrous salt and ferric salt to the water, and Fe 2+ / Fe 3+ = 2 ( (Molar ratio) in an aqueous solution containing Fe 2+ and Fe 3+ , (c) alkali is added to this aqueous solution, and adjusted to hydroxide ions / total Fe = 2 (molar ratio). Steps (a) to (c) are carried out in a non-oxidizing atmosphere using a closed mixing tank. (E) The generated precipitate is taken out of the closed mixing tank and solid-liquid separated. The alkali was added to adjust to strong alkalinity of pH 11 to 13, and (g) this strongly alkaline precipitate was returned to the closed mixing tank and added to the ferrous salt aqueous solution of (b) above, in a non-oxidizing atmosphere and at pH 8 to 11 by generating a precipitate under the liquidity of 11 and repeating the steps (e) to (g) while adjusting the contact area with the air interface,
It contains iron ferrite, or iron ferrite and reducing iron hydroxide together with green last, and consists of reducing iron-based precipitates mainly composed of green last. Iron ferrite is a product of slow oxidation of green last. The ratio of divalent iron to total iron in the iron-based precipitate is [Fe 2+ / total Fe] of 0.3 or more , and the oxidation-reduction potential (Ag / AgCl) of the slurry dispersed in water. A method for producing a reducing water purification material having an electrode reference) of −500 mV to −800 mV.
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