WO1993001136A1 - Traitement par oxydation amelioree de nappes phreatiques et d'effluents contamines - Google Patents

Traitement par oxydation amelioree de nappes phreatiques et d'effluents contamines Download PDF

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Publication number
WO1993001136A1
WO1993001136A1 PCT/CA1992/000273 CA9200273W WO9301136A1 WO 1993001136 A1 WO1993001136 A1 WO 1993001136A1 CA 9200273 W CA9200273 W CA 9200273W WO 9301136 A1 WO9301136 A1 WO 9301136A1
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WO
WIPO (PCT)
Prior art keywords
accordance
groundwater
transition metal
liquid effluent
ions
Prior art date
Application number
PCT/CA1992/000273
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English (en)
Inventor
Keith G. Bircher
Stephen R. Cater
Tony De Marco
Wayne Mcphee
Ali Safarzadeh-Amiri
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Solarchem Enterprises Inc.
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Solarchem Enterprises Inc. filed Critical Solarchem Enterprises Inc.
Publication of WO1993001136A1 publication Critical patent/WO1993001136A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/30—Treatment of water, waste water, or sewage by irradiation
    • C02F1/32—Treatment of water, waste water, or sewage by irradiation with ultraviolet light
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/72—Treatment of water, waste water, or sewage by oxidation
    • C02F1/722—Oxidation by peroxides

Definitions

  • This invention relates to methods for treating liquid effluents or contaminated groundwaters to remove organic contaminants. More particularly, the invention relates to processes for removing organic contaminants by treatment with hydrogen peroxide and transition metal ions.
  • Fenton's reagent which comprises hydrogen peroxide and a source of ferrous ion, is a strong oxidising agent and its use for the removal of certain organic contaminants from industrial effluents and groundwaters has been reported.
  • Canadian Patent No. 646,440 discloses a process for treating solutions containing phenolic compounds with hydrogen peroxide and metallic iron or ferrous ions. The patent does not disclose treatment of actual industrial wastes containing phenolic compounds.
  • the inventors have also devised a treatment method combining Fenton's reagent and UV irradiation for destruction of groundwater contaminants.
  • This method is advantageous for treating low levels of contaminants, ie. parts per billion (ppb) to low parts per million (ppm) range.
  • ppb parts per billion
  • ppm parts per million
  • UV light cannot penetrate deeply enough into the solution for the treatment to be fully effective.
  • a non-photochemical pre-treatment method to reduce the concentrations of contaminant to a level at which ultraviolet light becomes effective.
  • One possible treatment is the use of Fenton's reaction. There are, however, some drawbacks to Fenton's reaction as currently practised.
  • a method is provided of enhancing the rate of oxidation of organic contaminants in a liquid effluent or groundwater by hydrogen peroxide and ions of at least one transition metal, the method comprising promoting conversion of the transition metal ions from an oxidised to a reduced form.
  • a method is provided of enhancing the rate of oxidation of organic contaminants in a liquid effluent or groundwater by hydrogen peroxide and ions of at least one transition metal, by promoting conversion of the transition metal ions from an oxidised to a reduced form, the method comprising the steps of: (a) providing a liquid effluent or groundwater containing organic contaminants;
  • a method is provided of enhancing the rate of oxidation of organic contaminants in a liquid effluent or groundwater by hydrogen peroxide and ions of at least one transition metal, by promoting conversion of the transition metal ions from an oxidised to a reduced form, the method comprising the steps of:
  • Figure 1 shows toluene concentration as a function of time when BTX water was treated with Fenton's reagent at 20°C.
  • Figure 2 shows reaction time at various temperatures when PCP contaminated liquid effluent was treated by the process of the invention.
  • Figure 3 shows toluene destruction as a function of time when BTX water was treated by the process of the invention at various temperatures.
  • Figure 4 shows the destruction of benzene, toluene and xylenes by Fe 2+ /H 2 0 2 at 70°C and pH 3 as a function of time; concentration of H 2 0 2 and Fe 2+ are also shown.
  • Figure 5 shows the effect of initial Fe 2+ concentration on the destruction of toluene at 50°C.
  • Figure 6 shows the effect of temperature on the rate of toluene destruction by Fe 2+ /H 2 0 2 (20 ppm : 150 ppm) .
  • Figure 7 shows the destruction of toluene at 50°C and pH 3 by Fe 2+ /H 2 0 2 and Fe 3+ /H 2 0 2 .
  • Figure 8 shows the temperature dependence of the decomposition rate constant of H 2 0 2 by Fe 3+ in distilled water.
  • Figure 9 shows the effect of peroxide and resorcinol on the destruction of total BTX at 50°C and pH 3.
  • Figure 10 shows the destruction of toluene at 50°c and pH 3 as a function of time, with and without addition of resorcinol.
  • Figure 11 shows the destruction of toluene at 60°C and pH 3 by Fe 3+ /H 2 0 2 , 65:300 ⁇ or by Fe 3+ /H 2 0 2 /resorcinol, 62:300:15 ⁇ . Fe 2+ concentrations during these treatments are shown as D and 0 respectively.
  • Figure 12 is a schematic diagram of a suitable apparatus for treating liquid effluents by the process of the invention.
  • Figure 13 shows the effect of pH on the destruction rate constant of toluene by Fe 2+ /H 2 0 2 (20:150) at 50°C.
  • Liquid effluents and groundwaters include wastes resulting from industrial processes and contaminated groundwaters resulting from spills or leakage at industrial or storage sites.
  • such liquid effluents and groundwaters may be contaminated with organic compounds including aromatic hydrocarbons such as benzene, toluene and xylene, substituted analogues of these compounds, phenol and substituted phenols such as pentachlorophenol (PCP), ethers such as 1,4-dioxane or tetrahydrofuran, ketones such as acetone or methylethylketone or chlorinated organics such as chloroform.
  • aromatic hydrocarbons such as benzene, toluene and xylene
  • substituted analogues of these compounds phenol and substituted phenols
  • PCP pentachlorophenol
  • ethers such as 1,4-dioxane or tetrahydrofuran
  • ketones such as acetone or methyl
  • Transition metal ions other than iron may also be used in a similar oxidative process, copper and zinc being preferred, although iron is especially preferred.
  • the present inventors have found, surprisingly, that it is possible to promote conversion of the oxidised form of the transition metal ions to the reduced form, thereby enhancing the rate of oxidation of contaminants and overcoming the above-described problems.
  • This promotion was achieved by the application of heat during the oxidation or by addition to the reaction mixture of a promoter compound.
  • the temperature required to give enhanced oxidation of organic contaminants referred to herein as the "effective temperature”
  • the effective temperature varied depending on the particular organic contaminant to be treated, and also on the other constituents present in the liquid effluent or groundwater.
  • Figure 2 shows the treatment of wood treatment process water containing PCP. At 50°, the rate of destruction of PCP was too slow to be monitored. At 60°C, the rate had increased and at 70°C the reaction was complete in less than 60 minutes.
  • Enhanced oxidation of PCP required an effective temperature of at least about 60°C.
  • FIGS 3 and 4 show the treatment of gasoline wastes at different temperatures.
  • Gasoline wastes typically contain benzene, toluene, ethylbenzene and xylene (the term “xylene” includes the three possible isomers of the compound) and are referred to herein as "BTX waters”. These waters also contain other aromatic hydrocarbons along with methyl t-butyl ether. The data on toluene destruction described herein are representative of the destruction of all the above- listed components of BTX waters.
  • Enhanced oxidation of the contaminants in BTX waters required an effective temperature of at least about 40°C.
  • tap water spiked to the same concentration with benzene, toluene and xylene (BTX) was readily treated at 25°C.
  • Fe 3+ is used instead of Fe 2+ in the treatment of toluene, there is a much smaller initial drop in toluene concentration, followed by a second phase rate comparable to that seen with Fe 2+ , as seen in Figure 7.
  • the effect of Fe 3+ concentration on toluene destruction and the effect of temperature at a given Fe 3+ concentration were found to be similar to those observed for Fe 2+ .
  • Temperature also affects the rate of H 2 0 2 decomposition in the presence of Fe 3+ , with a linear relationship between the logarithm of the rate constant versus the reciprocal of temperature, as seen in Figure 8. This suggests that one effect of temperature is to improve the reduction of Fe 3+ to Fe 2+ : heat Fe 3+ + H 2 0 2 ⁇ Fe 2+ H0 2 . + H +
  • Promoter compounds include phenol, catechol, resorcinol, hydroquinone and their quinone oxidation products.
  • Figures 9, 10 and 11 show the enhanced oxidation of BTX when resorcinol was added as promoter compound. The enhanced oxidation was seen when either Fe 2+ or Fe 3+ was initially added as transition metal ion.
  • Figure 11 shows that Fe 2+ concentration increased, to a level of 10-12 ppm, as toluene concentration dropped, giving support to the idea that addition of resorcinol facilitates the conversion of Fe 3+ to Fe 2+ .
  • the process of the invention also gave enhanced oxidation of the contaminants 1,4-dioxane, acetone, chloroform and methylethylketone (MEK) .
  • 1,4-dioxane was also destroyed by thermal enhanced oxidation by Fenton's reagent, as seen in Table 2, as was MEK. Thermal enhanced oxidation of 1,4-dioxane was seen at an effective temperature of at least about 60°C and MEK at at least about 55°C.
  • the present invention provides a novel and convenient method for treating liquid effluents or groundwater containing many organic contaminants which were heretofore resistant to treatment by Fenton's reaction, as described above.
  • Classes of organic contaminants which may be treated by the process of the invention include ethers, aromatics, polyaromatics, nitroaromatics, chlorinated aromatics, phenols and chlorinated phenols, ketones, aldehydes, chlorinated alkanes and alkenes and alcohols.
  • the organic contaminants may be compounds selected from the group of compounds consisting of an alkyl or alkenyl which may be linear, branched or cyclic preferably having 1 to 20 carbon atoms which may be substituted by one or more of fluorine, chlorine, bromine, nitro, sulfo, carboxyl, hydroxyl or c,-C 10 -alkoxy, preferably trichloroethane, trichloroethylene, and chloroform, an aromatic or polyaromatic compounds which may be substituted by one or more of alkyl or alkenyl which may be linear or branched and preferably having 1 to 10 carbon atoms, fluorine, chlorine, bromine, nitro, sulfo, carboxyl, hydroxyl or c,-C, 0 -alkoxy, preferably benzene, toluene, phenolics which may be substituted by one or more atoms of fluorine, chlorine, bromine, biphenyl which may be substituted by one or
  • Particularly preferred organic contaminants which may be treated by the process of the invention include benzene, toluene, xylene, ethylbenzene, methyl-t-butyl ether, chlorobenzenes, polyaromatic hydrocarbons (naphthalene, anthracene) , trichloroethane, trichloroethylene, dioxane, ketones, phenols and chlorinated phenols, alcohols, PCBs, chloroform and trinitrotoluene.
  • a suitable apparatus for treatment of liquid effluents or groundwaters by the process of the invention is illustrated in Figure 12.
  • the liquid effluent or groundwater is placed in the mixing tank and is heated to the effective temperature before being contacted with hydrogen peroxide and transition metal ions and is maintained at that temperature during their addition and throughout the period of oxidation of the contaminants.
  • the liquid effluent or groundwater is contacted with the hydrogen peroxide and transition metal ions at an acidic pH.
  • the liquid effluent or groundwater is adjusted to an acidic pH in the range of between 1 and 5.
  • the pH is adjusted to 3.
  • Hydrogen peroxide is preferably added to the liquid effluent or groundwater as an aqueous solution. A sufficient amount of hydrogen peroxide is added based on the concentration of the organic contaminants in the liquid effluent or groundwater. It is appreciated that not all of the organic contaminants have to be removed from a liquid effluent or groundwater to provide an environmentally acceptable liquid effluent or groundwater.
  • the total organic content of the liquid effluent or groundwater may be measured by known techniques and the amount of H 2 0 2 needed in the method of the invention to remove the desired organic contaminant portion thereof can be readily calculated. Typically for purposes of this invention between 1 and 10 ppm of H 2 0 2 are added per 1 ppm of organic contaminants in the liquid effluent or groundwater.
  • Transition metal ions are added in the form of a suitable salt. Copper, zinc and/or iron compounds are preferably used as sources of transition metal ions, iron compounds being most particularly preferred. Iron compounds such as Fe(0H) 3 , Fe 2 0 3 , FeCl 3 , Fe 2 (S0 4 ) 3 , FeO,
  • Fe(OH) 2 , FeCl 2 , FeC0 3 or FeS0 4 may be used in the process of the present invention.
  • FeS0 4 .7H 2 0 may be used as the source of iron ions.
  • the concentration of transition metal ions is selected based on the concentration of the organic contaminants in the liquid effluent or groundwater, and desired degree of removal of the organic contaminants.
  • the hydrogen peroxide and transition metal ions should desirably be mixed into the liquid effluent or groundwater as effectively as possible in order to maximize the effectiveness of the hydrogen peroxide and iron ions in the method.
  • the liquid effluent or groundwater is continued in contact with the hydrogen peroxide and transition metal ions at the effective temperature with mixing until the desired level of contaminant is reached.
  • the order in which the steps of heating, pH adjustment and reagent addition are carried out is not critical and appropriate sequences of steps will be known to those skilled in the art.
  • the liquid effluent or groundwater is adjusted to an acidic pH, as described for thermal enhancement, and contacted with hydrogen peroxide, transition metal ions and a promoter compound with effective mixing.
  • Hydrogen peroxide and transition metal ion additions are as described above for thermal enhancement.
  • promoter compound typically for purposes of this invention, between 10 and 100 ppm of promoter compound is added to the liquid effluent or groundwater.
  • enhanced oxidation of organic contaminants by the method of the invention may be used as a pre- treatment, to reduce the level of contaminant partially, the remaining contaminant being reduced to discharge levels by exposure of the liquid effluent or contaminated groundwater to ultra violet light in the range 200 - 400 nm.
  • enhanced oxidation of organic contaminants may be combined with recycling of the transition metal used in the oxidation process.
  • the liquid effluent or groundwater is adjusted to a pH in the range of about 6 to 9 which precipitates the transition metal present as the hydroxide eg. Fe(OH) 3 if iron is used.
  • the precipitate is recovered, for example by settling or filtration and acidified to a pH of 0 to 2 to redissolve the transition metal which is re-used in the process of the invention.
  • Liquid effluent from a wood treatment process which had a chemical oxygen demand of 4000 mg/L and was contaminated with PCP was obtained.
  • 29L of effluent was placed in the mixing tank of the batch re-circulation system of Figure 12 and pH adjusted to 3 by addition of sulphuric acid.
  • the effluent was heated to 50°C, ferrous sulphate was added to give 100 ppm and then 4000 ppm H 2 0 2 was added.
  • PCP concentration was monitored at desired time intervals using high pressure liquid chromatography (HPLC) .
  • a sample of BTX water was obtained from an industrial source. 29L portions were actified to pH 3 and treated, at various temperatures, with ferrous sulphate (20 ppm) and H 2 0 2 (350 ppm) , as described in Example 1.
  • 29L tap water was placed in the mixing tank of Figure 12, pH was adjusted to 3 by addition of sulphuric acid and the liquid was heated to 50°C. Toluene was added to give a concentration of 100 ppm, the solution being circulated at 60Lpm for 60 minutes to dissolve the toluene.
  • Fe 2+ was added to the desired level (levels of 10, 20, 30 and 40 ppm were tested) and H 2 0 2 was added to give 150 ppm. Samples were taken at regular time intervals and analysed for H 2 0 2 , Fe 2+ and toluene.
  • H 2 0 2 was measured by titration with eerie sulphate and Fe 2+ was measured colorimetrically by complexing with o-phenanthroline. The results are shown in Figure 3.

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  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Treatment Of Water By Oxidation Or Reduction (AREA)

Abstract

On décrit un procédé permettant d'améliorer le taux d'oxydation de contaminants organiques dans un effluent liquide par l'intermédiaire de peroxyde d'hydrogène et d'ions d'au moins un métal de transition, le procédé consistant à favoriser la conversion des ions de métaux de transition à partir d'une forme oxydée en une forme réduite.
PCT/CA1992/000273 1991-07-05 1992-06-26 Traitement par oxydation amelioree de nappes phreatiques et d'effluents contamines WO1993001136A1 (fr)

Applications Claiming Priority (2)

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US72441991A 1991-07-05 1991-07-05
US724,419 1991-07-05

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WO1993001136A1 true WO1993001136A1 (fr) 1993-01-21

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104374726A (zh) * 2014-11-28 2015-02-25 苏州佑君环境科技有限公司 一种三氯乙烯检测试剂及其制备方法
CN107055740A (zh) * 2017-04-13 2017-08-18 河海大学 一种对苯二酚促进铁氧化物催化过氧化氢降解橙黄g废水的方法
CN110040911A (zh) * 2019-05-06 2019-07-23 孙鹏 一种含铜高盐印染废水的处理方法
CN111646615A (zh) * 2020-06-15 2020-09-11 北京环球中科水务科技有限公司 撬装式光芬顿水处理设备
CN113087119A (zh) * 2021-05-08 2021-07-09 北京启元汇通水务科技股份有限公司 促进芬顿氧化的方法、促进芬顿氧化反应体系及应用
WO2022119976A1 (fr) 2020-12-01 2022-06-09 Aptevo Research And Development Llc Anticorps hétérodimétriques bispécifiques se liant à cd3 et psma

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62282688A (ja) * 1986-05-30 1987-12-08 Nippon Denki Kankyo Eng Kk 有機物含有水の処理方法
EP0360989A1 (fr) * 1988-09-24 1990-04-04 Kernforschungszentrum Karlsruhe Gmbh Procédé pour le traitement par oxydation chimique d'eau, qui contient des substances toxiques et/ou par ou difficilement dégradables biologiquement
EP0378888A1 (fr) * 1986-12-29 1990-07-25 E.I. Du Pont De Nemours And Company Destruction de nitrophénols
WO1991013032A1 (fr) * 1990-02-26 1991-09-05 Solarchem Enterprises Inc. Traitement d'effluents et de nappes phreatiques pollues

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62282688A (ja) * 1986-05-30 1987-12-08 Nippon Denki Kankyo Eng Kk 有機物含有水の処理方法
EP0378888A1 (fr) * 1986-12-29 1990-07-25 E.I. Du Pont De Nemours And Company Destruction de nitrophénols
EP0360989A1 (fr) * 1988-09-24 1990-04-04 Kernforschungszentrum Karlsruhe Gmbh Procédé pour le traitement par oxydation chimique d'eau, qui contient des substances toxiques et/ou par ou difficilement dégradables biologiquement
WO1991013032A1 (fr) * 1990-02-26 1991-09-05 Solarchem Enterprises Inc. Traitement d'effluents et de nappes phreatiques pollues

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
JOURNAL OF THE WATER POLLUTION CONTROL FEDERATION. vol. 36, no. 9, September 1964, WASHINGTON US pages 1116 - 1128; HUGH 5. EISENHAUER: 'OXIDATION OF PHENOLIC WASTES' cited in the application *
PATENT ABSTRACTS OF JAPAN vol. 12, no. 176 (C-498)(3023) 25 May 1988 & JP,A,62 282 688 ( NIPPON DENKI KANKYO ENG KK ) 8 December 1987 *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104374726A (zh) * 2014-11-28 2015-02-25 苏州佑君环境科技有限公司 一种三氯乙烯检测试剂及其制备方法
CN107055740A (zh) * 2017-04-13 2017-08-18 河海大学 一种对苯二酚促进铁氧化物催化过氧化氢降解橙黄g废水的方法
CN110040911A (zh) * 2019-05-06 2019-07-23 孙鹏 一种含铜高盐印染废水的处理方法
CN110040911B (zh) * 2019-05-06 2021-07-06 孙鹏 一种含铜高盐印染废水的处理方法
CN111646615A (zh) * 2020-06-15 2020-09-11 北京环球中科水务科技有限公司 撬装式光芬顿水处理设备
WO2022119976A1 (fr) 2020-12-01 2022-06-09 Aptevo Research And Development Llc Anticorps hétérodimétriques bispécifiques se liant à cd3 et psma
CN113087119A (zh) * 2021-05-08 2021-07-09 北京启元汇通水务科技股份有限公司 促进芬顿氧化的方法、促进芬顿氧化反应体系及应用

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Publication number Publication date
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