JP2787524B2 - Hydrogen sulfide remover - Google Patents
Hydrogen sulfide removerInfo
- Publication number
- JP2787524B2 JP2787524B2 JP4160139A JP16013992A JP2787524B2 JP 2787524 B2 JP2787524 B2 JP 2787524B2 JP 4160139 A JP4160139 A JP 4160139A JP 16013992 A JP16013992 A JP 16013992A JP 2787524 B2 JP2787524 B2 JP 2787524B2
- Authority
- JP
- Japan
- Prior art keywords
- hydrogen sulfide
- akaganite
- feooh
- particles
- removing 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.)
- Expired - Fee Related
Links
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- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
- Treating Waste Gases (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は硫化水素除去剤に関す
る。The present invention relates to a hydrogen sulfide removing agent.
【０００２】[0002]
【従来の技術】下水、し尿処理場、製鉄場等では悪臭の
発生が問題となっているが、悪臭物質主成分の一つとし
て硫化水素が挙げられる。従来硫化水素を除去する方法
としては、次亜塩素酸ナトリウム（ＮａＣｌＯ）や塩化
第二鉄（ＦｅＣｌ３）、硫酸第二鉄（Ｆｅ ２ （ＳＯ４）
３）、ポリ鉄（Ｆｅ２（ＳＯ４）２＋ｎ（Ｏ
Ｈ）２−ｎ）等の酸化剤を用いて次の、（１）、（２）
式で示すように硫化水素を酸化し、イオウとして固定す
る方法が採用されていた。 ＣｌＯ−＋Ｈ２Ｓ→Ｃｌ−＋Ｈ２Ｏ＋Ｓ↓ （１） ２Ｆｅ３＋＋Ｈ２Ｓ→２Ｆｅ２＋＋２Ｈ＋＋Ｓ↓ （２）2. Description of the Related Art Odor is a problem in sewage, human waste treatment plants, steel mills and the like, but hydrogen sulfide is one of the main components of malodorous substances. Conventional methods for removing hydrogen sulfide include sodium hypochlorite (NaClO), ferric chloride (FeCl 3 ), and ferric sulfate (Fe 2 (SO 4 )).
3 ), polyiron (Fe 2 (SO 4 ) 2 + n (O
H) The following (1) and (2) using an oxidizing agent such as 2-n )
As shown in the equation, a method has been adopted in which hydrogen sulfide is oxidized and fixed as sulfur. ClO - + H 2 S → Cl - + H 2 O + S ↓ (1) 2Fe 3+ + H 2 S → 2Fe 2+ + 2H + + S ↓ (2)
【０００３】[0003]
【発明が解決しようとする課題】しかしながら上記の下
水、し尿処理場、製鉄所等では、硫化水素以外の汚染物
質も発生し、その中には多量の有機質が含まれているの
で、硫化水素以外の有機質の酸化及び分解にも酸化剤が
用いられてしまい、酸化剤による硫化水素の除去の効率
が低下し、酸化剤を多量に添加しながらも硫化水素を十
分に除去することができない。その上大きな反応速度の
得られるｐＨ領域が狭いことから、処理操作が面倒であ
るという問題がある。However, pollutants other than hydrogen sulfide are also generated in the above-mentioned sewage, human waste treatment plant, steelworks, etc., and a large amount of organic substances are contained therein. The oxidizing agent is also used for the oxidation and decomposition of the organic matter, and the efficiency of removing the hydrogen sulfide by the oxidizing agent is reduced, and the hydrogen sulfide cannot be sufficiently removed even though a large amount of the oxidizing agent is added. In addition, since the pH range where a large reaction rate can be obtained is narrow, there is a problem that the processing operation is troublesome.
【０００４】また酸化剤として三価の鉄系化合物を用い
る場合には、上述の様に硫化水素の除去率が低いため鉄
系酸化剤の投入量が多いことから、有機化合物及び硫化
水素が三価の鉄イオンを還元した時に多量の水酸化第一
鉄（Ｆｅ（ＯＨ）２）を生成し、この水酸化第一鉄は空
気中及び排水中の溶存酸素と反応して含水酸化第二鉄
（Ｆｅ２Ｏ３・ｎＨ２Ｏ）となるが、含水酸化第二鉄は
凝集作用が弱いためコロイド溶液になり、この為放流水
が濁ってしまうという問題がある。When a trivalent iron-based compound is used as an oxidizing agent, the amount of the iron-based oxidizing agent is large because the removal rate of hydrogen sulfide is low as described above. A large amount of ferrous hydroxide (Fe (OH) 2 ) is generated when reducing trivalent iron ions, and this ferrous hydroxide reacts with dissolved oxygen in air and wastewater to contain ferric hydroxide. (Fe 2 O 3 .nH 2 O), but the ferric hydroxide has a weak agglomeration action and becomes a colloidal solution, which causes a problem that the discharged water becomes cloudy.
【０００５】本発明はこのような事情のもとになされた
ものであり、その目的は高い硫化水素の除去率を得るこ
とができ、排水の濁りもない硫化水素除去剤を提供する
ことにある。The present invention has been made under such circumstances, and an object of the present invention is to provide a hydrogen sulfide removing agent which can obtain a high removal rate of hydrogen sulfide and has no turbidity in wastewater. .
【０００６】[0006]
【課題を解決するための手段】本発明は塩化第一鉄液を
反応槽内に投入し、温度７５〜８５℃及び加圧雰囲気下
で空気または酸素により酸化し、沈殿物をろ過して得ら
れた、針状結晶が球状に密集したアカガナイトよりなる
硫化水素除去剤である。According to the present invention, there is provided a ferrous chloride solution.
Put in the reaction tank, temperature 75-85 ° C and under pressurized atmosphere
Oxidation with air or oxygen at
Made of akaganite with dense needle-like crystals
It is a hydrogen sulfide removing agent .
【０００７】[0007]
【作用】アカガナイトは化学式β−ＦｅＯＯＨで表され
る鉄化合物であり、アカガナイトを硫化水素除去剤とし
て用いると、次の（３）式に示すアカガナイトと硫化水
素とにより硫化第二鉄（Ｆｅ２Ｓ３）を生成する化学反
応が効率よく進行し、高い硫化水素の除去率が得られ
る。 ２ＦｅＯＯＨ＋３Ｈ２Ｓ→Ｆｅ２Ｓ３＋４Ｈ２Ｏ （３）Akaganite is an iron compound represented by the chemical formula β-FeOOH. When akaganite is used as a hydrogen sulfide removing agent, ferric sulfide (Fe 2 S) is formed by akaganite and hydrogen sulfide represented by the following formula (3). The chemical reaction for producing 3 ) proceeds efficiently, and a high hydrogen sulfide removal rate can be obtained. 2FeOOH + 3H 2 S → Fe 2 S 3 + 4H 2 O (3)
【０００８】[0008]
【実施例】図１は本発明の硫化水素除去剤としてのアカ
ガナイト粒子の結晶構造図、図２はアカガナイト生成の
際の粒度分布を表すグラフ、図３はアカガナイトの硫化
水素除去剤としての効能を調べるための実験装置の側面
図である。FIG. 1 is a crystal structure diagram of akaganite particles as a hydrogen sulfide removing agent of the present invention, FIG. 2 is a graph showing a particle size distribution when akaganite is formed, and FIG. It is a side view of the experimental device for investigating.
【０００９】本発明の硫化水素除去剤はアカガナイトか
らなり、アカガナイトは正方晶系（格子定数ａ＝１０．
４８、ｃ＝３．０６）の結晶構造を持つ化学式β−Ｆｅ
ＯＯＨの鉄化合物である。The hydrogen sulfide removing agent of the present invention comprises akaganite, and the akaganite is tetragonal (lattice constant a = 10.
48, a chemical formula β-Fe having a crystal structure of c = 3.06)
OOH is an iron compound.
【００１０】このアカガナイトは例えば（４）式に示す
ように、塩化第一鉄（ＦｅＣｌ２）液を空気、酸素で酸
化することにより生成される。 ６ＦｅＣｌ２＋１．５Ｏ２＋Ｈ２Ｏ→２ＦｅＯＯＨ＋４ＦｅＣｌ３ （４） この塩化第一鉄液としては例えば塩化第二鉄エッチング
液のエッチング廃液を用いることができる。そして反応
槽内に塩化第一鉄液を投入し、温度７５〜８５℃、装置
内圧力１．９ｋｇ／ｃｍ２状態で１６〜１７時間反応さ
せ、その沈殿物をフィルターでろ過して行われる。装置
内圧力一定のもとで塩化第一鉄消失濃度と経過時間との
関係は直線的であり、反応時間１６〜１７時間で酸化率
７０〜８０％に達成した。取得したアカガナイト粒子は
図１からわかるように、針状結晶が球状に密集した形状
である。また粒度分布を調べたところ図２に示すグラフ
が得られ、平均粒径は８．３μｍであった。The akaganite is produced by oxidizing a ferrous chloride (FeCl 2 ) solution with air and oxygen as shown in, for example, equation (4). 6FeCl The 2 + 1.5O 2 + H 2 O → 2FeOOH + 4FeCl 3 (4) This ferrous chloride solution may be used, for example etching waste liquid of ferric chloride etchant. Then, a ferrous chloride solution is charged into the reaction tank, reacted at a temperature of 75 to 85 ° C. and a pressure of 1.9 kg / cm 2 in the apparatus for 16 to 17 hours, and the precipitate is filtered through a filter. The relation between the disappearance concentration of ferrous chloride and the elapsed time was linear under a constant pressure in the apparatus, and an oxidation rate of 70 to 80% was achieved in a reaction time of 16 to 17 hours. As can be seen from FIG. 1, the obtained akaganite particles have a shape in which needle-like crystals are densely packed in a spherical shape. When the particle size distribution was examined, a graph shown in FIG. 2 was obtained, and the average particle size was 8.3 μm.
【００１１】以上の方法で得られたアカガナイトの硫化
水素除去剤としての効能は以下の実験方法により調べ
た。 （１）実験方法 図３に示すように三角フラスコ１中の０．２５％硫化ナ
トリウム（Ｎａ２Ｓ）と１２％塩酸（ＨＣｌ）溶液の反
応により発生した硫化水素（Ｈ２Ｓ）を、パン型造粒機
により形成し１０５℃で乾燥させたアカガナイトよりな
る硫化水素除去剤３１を充填したガラスカラム３に吸引
して通過させ、硫化水素の入口濃度と出口濃度を検知管
により測定した。硫化水素濃度は窒素（Ｎ２）ガスによ
り希釈調整し、反応条件は、カラムのサイズ：４０φ×
３５０ｍｍ、アカガナイトの充填量：１００ｇ、アカガ
ナイトの充填高さ：１２ｃｍ、硫化水素流量：２２００
ｃｃ／ｍｉｎ、硫化水素濃度：７０００ｐｐｍ、流速：
１．８ｍ／ｍｉｎとした。 （２）実験結果 硫化水素の濃度は、入口濃度７０００ｐｐｍに対し出口
濃度５０ｐｐｍであった。 （３）考察 アカガナイトによる硫化水素除去は、アカガナイトと硫
化水素の（３）式に示すような硫化第二鉄（Ｆｅ
２Ｓ３）生成の化学反応によるものと考えられる。 ２ＦｅＯＯＨ＋３Ｈ２Ｓ→Ｆｅ２Ｓ３＋４Ｈ２Ｏ （３） そしてこの時生成した硫化第二鉄は、（５）式に示すよ
うに空気酸化により再生が可能である。 ２Ｆｅ２Ｓ３＋３Ｏ２＋２Ｈ２Ｏ→４ＦｅＯＯＨ＋６Ｓ （５） 化学式ＦｅＯＯＨで表される物質（含水酸化鉄）として
は、アカガナイトの他にアカガナイトと結晶構造が異な
るα−ＦｅＯＯＨ（Ｇｏｅｔｈｉｔｅ）とγ−ＦｅＯＯ
Ｈ（Ｌｅｐｉｄｃｒｏｃｉｔｅ）などが存在する。α−
ＦｅＯＯＨ、γ−ＦｅＯＯＨは共に斜方晶系の結晶構造
を持ち、粒子の形状は針状の鉄化合物である。α−Ｆｅ
ＯＯＨの粒子の結晶構造図を図４に示す。これらα−Ｆ
ｅＯＯＨやγ−ＦｅＯＯＨについても化学式からは
（３）式の反応が進行するが、硫化水素の除去率は非常
に小さく、実際上硫化水素除去剤としては使用すること
ができない。その理由については、それぞれの粒子の写
真からわかるように、アカガナイト粒子の形状がα−Ｆ
ｅＯＯＨやγ−ＦｅＯＯＨ粒子の針状結晶とは明らかに
異なり、針状結晶が球状に密集した、硫化水素が吸着し
やすい形状であることが要因の一つであると思われる。The effectiveness of the akaganite obtained as described above as a hydrogen sulfide removing agent was examined by the following experimental method. (1) Experimental Method As shown in FIG. 3, hydrogen sulfide (H 2 S) generated by the reaction of 0.25% sodium sulfide (Na 2 S) and 12% hydrochloric acid (HCl) solution in Erlenmeyer flask 1 was panned. The glass column 3 filled with a hydrogen sulfide removing agent 31 made of akaganite formed by a mold granulator and dried at 105 ° C. was suctioned and passed through, and the inlet concentration and the outlet concentration of hydrogen sulfide were measured by a detector tube. The concentration of hydrogen sulfide was adjusted by diluting with nitrogen (N 2 ) gas, and the reaction conditions were as follows: column size: 40φ ×
350 mm, filling amount of akaganite: 100 g, filling height of akaganite: 12 cm, flow rate of hydrogen sulfide: 2200
cc / min, hydrogen sulfide concentration: 7000 ppm, flow rate:
It was 1.8 m / min. (2) Experimental Results The concentration of hydrogen sulfide was 50 ppm at the outlet with respect to 7000 ppm at the inlet. (3) Discussion The removal of hydrogen sulfide by akaganite is based on ferric sulfide (Fe) as shown in equation (3) for akaganite and hydrogen sulfide.
It is thought to be due to a chemical reaction of 2 S 3 ) formation. 2FeOOH + 3H 2 S → Fe 2 S 3 + 4H 2 O (3) The sulfide ferric generated at this time, it is possible to reproduce by air oxidation as shown in equation (5). 2Fe 2 S 3 + 3O 2 + 2H 2 O → 4FeOOH + 6S (5) As a substance (hydrous iron oxide) represented by the chemical formula FeOOH, besides akaganite, α-FeOOH (Goethite) and γ-FeOO having different crystal structures from akaganite are used.
H (Lepidcrocite) exists. α-
Both FeOOH and γ-FeOOH have an orthorhombic crystal structure, and the particles are acicular iron compounds. α-Fe
FIG. 4 shows a crystal structure diagram of the OOH particles. These α-F
With respect to eOOH and γ-FeOOH, the reaction represented by the formula (3) proceeds from the chemical formula, but the removal rate of hydrogen sulfide is extremely small, so that it cannot practically be used as a hydrogen sulfide removing agent. The reason for this is that, as can be seen from the photographs of the respective particles, the shape of the akaganite particles is α-F
It is apparently different from the needle-like crystals of eOOH and γ-FeOOH particles, and one of the factors is that the needle-like crystals are spherically dense and have a shape in which hydrogen sulfide is easily adsorbed.
【００１２】即ちＦｅＯＯＨが化学式の上からは硫化水
素と反応するとはいっても、実際にはβ−ＦｅＯＯＨ
（アカガナイト）のみが硫化水素除去剤として使用でき
る物質であり、しかもこの硫化水素除去剤は、先述した
実験結果からわかるように、１００ｇの使用に対して硫
化水素濃度を７０００ｐｐｍから５０ｐｐｍへ減少でき
るので、極めて高い硫化水素の除去率を得ることができ
る。That is, although FeOOH reacts with hydrogen sulfide from the chemical formula, β-FeOOH is actually
(Akaganite) is the only substance that can be used as a hydrogen sulfide remover. Further, as can be seen from the above-mentioned experimental results, the hydrogen sulfide remover can reduce the hydrogen sulfide concentration from 7000 ppm to 50 ppm for use of 100 g. , An extremely high removal rate of hydrogen sulfide can be obtained.
【００１３】また（従来の技術）の項で述べたように、
ポリ鉄と硫化水素とを反応させたときに水酸化第一鉄を
介して得られる含水酸化鉄（Ｆｅ２Ｏ３・ｎＨ２Ｏ）は
ｎ＝１としたときに２ＦｅＯＯＨと表されるが、この場
合のＦｅＯＯＨは硫化水素をほとんど除去しないため、
α−ＦｅＯＯＨやγ−ＦｅＯＯＨであると推察される。Also, as described in the section (Prior Art),
Hydrous iron oxide (Fe 2 O 3 .nH 2 O) obtained via ferrous hydroxide when polyiron reacts with hydrogen sulfide is expressed as 2FeOOH when n = 1, Since FeOOH in this case hardly removes hydrogen sulfide,
It is presumed to be α-FeOOH or γ-FeOOH.
【００１４】このように本発明は、ＦｅＯＯＨで表され
る含水酸化鉄に着目すると共に、その中からアカガナイ
ト（β−ＦｅＯＯＨ）のみが硫化水素と効率よく反応
し、硫化水素除去剤として高い硫化水素の除去率を得る
ことができることを見い出したものである。As described above, the present invention focuses on hydrous iron oxide represented by FeOOH, and among them, only akaganite (β-FeOOH) efficiently reacts with hydrogen sulfide. It has been found that the removal rate can be obtained.
【００１５】またアカガナイトの原料である塩化第一鉄
は、塩化第二鉄エッチング液のエッチング廃液からの生
成が可能であるのでコストが安価である。Ferrous chloride, which is a raw material of akaganite, can be produced from an etching waste solution of a ferric chloride etching solution, so that the cost is low.
【００１６】なおアカガナイトの原料及び製法は上述の
実施例に限定されるものではない。The raw material and production method of akaganite are not limited to the above-mentioned embodiment.
【００１７】[0017]
【発明の効果】本発明によればアカガナイトを有効成分
とする硫化水素除去剤であるため、高い硫化水素の除去
率が得られ、例えば工場排液の処理に非常に有効であ
り、しかも、硫化水素除去後も再生が可能であるためコ
ストも安価になる。According to the present invention, since it is a hydrogen sulfide remover containing akaganite as an active ingredient, a high hydrogen sulfide removal rate can be obtained. For example, it is very effective for treating factory effluent. Regeneration is possible even after removal of hydrogen, so that the cost is reduced.
【図１】本発明の硫化水素除去剤としてのアカガナイト
粒子の結晶構造図である。FIG. 1 is a crystal structure diagram of akaganite particles as a hydrogen sulfide removing agent of the present invention.
【図２】アカガナイト生成の際の粒度分布を表すグラフ
である。FIG. 2 is a graph showing a particle size distribution at the time of generation of akaganite.
【図３】アカガナイトの硫化水素除去剤としての効能を
調べるための実験装置の側面図である。FIG. 3 is a side view of an experimental apparatus for examining the effectiveness of akaganite as a hydrogen sulfide removing agent.
【図４】α−ＦｅＯＯＨ粒子の結晶構造図である。FIG. 4 is a crystal structure diagram of α-FeOOH particles.
１ 三角フラスコ ２ マグネティックスターラー ３ ガラスカラム ３１ 硫化水素除去剤 DESCRIPTION OF SYMBOLS 1 Erlenmeyer flask 2 Magnetic stirrer 3 Glass column 31 Hydrogen sulfide remover
フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) B01J 20/00 - 20/34 B01D 53/34Continuation of front page (58) Field surveyed (Int.Cl. 6 , DB name) B01J 20/00-20/34 B01D 53/34
Claims (1)
７５〜８５℃及び加圧雰囲気下で空気または酸素により
酸化し、沈殿物をろ過して得られた、針状結晶が球状に
密集したアカガナイトよりなる硫化水素除去剤。 1. A ferrous chloride solution is charged into a reaction vessel, and the temperature is adjusted.
With air or oxygen at 75-85 ° C and pressurized atmosphere
The needle-like crystals obtained by oxidizing and filtering the precipitate are spherical.
Hydrogen sulfide remover consisting of dense akaganite.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4160139A JP2787524B2 (en) | 1992-05-27 | 1992-05-27 | Hydrogen sulfide remover |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4160139A JP2787524B2 (en) | 1992-05-27 | 1992-05-27 | Hydrogen sulfide remover |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05329362A JPH05329362A (en) | 1993-12-14 |
| JP2787524B2 true JP2787524B2 (en) | 1998-08-20 |
Family
ID=15708719
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4160139A Expired - Fee Related JP2787524B2 (en) | 1992-05-27 | 1992-05-27 | Hydrogen sulfide remover |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2787524B2 (en) |
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| JP4869543B2 (en) * | 2003-01-31 | 2012-02-08 | 新日本製鐵株式会社 | Wastewater purification method |
| JP3740491B1 (en) | 2004-07-23 | 2006-02-01 | 三井金属鉱業株式会社 | Fluorine adsorption / desorption agent capable of adsorbing and desorbing fluorine in electrolyte in zinc electrolytic smelting, and fluorine removal method using the fluorine adsorption / desorption agent |
| CN104667926B (en) * | 2013-11-29 | 2017-01-25 | 福建三聚福大化肥催化剂国家工程研究中心有限公司 | Low-temperature carbonyl sulfide hydrolysis catalyst and preparation method thereof |
-
1992
- 1992-05-27 JP JP4160139A patent/JP2787524B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107617328A (en) * | 2017-09-27 | 2018-01-23 | 北京三聚环保新材料股份有限公司 | A kind of compound Fe-series desulfurizing agent and preparation method and application |
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