EP0144416A1 - Method for reducing the hydrocarbon content in air or water - Google Patents

Method for reducing the hydrocarbon content in air or water

Info

Publication number
EP0144416A1
EP0144416A1 EP19840902471 EP84902471A EP0144416A1 EP 0144416 A1 EP0144416 A1 EP 0144416A1 EP 19840902471 EP19840902471 EP 19840902471 EP 84902471 A EP84902471 A EP 84902471A EP 0144416 A1 EP0144416 A1 EP 0144416A1
Authority
EP
European Patent Office
Prior art keywords
air
water
zeolite
content
reducing
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.)
Ceased
Application number
EP19840902471
Other languages
German (de)
French (fr)
Inventor
Sten Andersson
Lars FÄLTH
Kaj Vareman
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
MUNTERS ZEOL AB
Original Assignee
MUNTERS ZEOL AB
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
Priority claimed from SE8303268A external-priority patent/SE8303268D0/en
Application filed by MUNTERS ZEOL AB filed Critical MUNTERS ZEOL AB
Publication of EP0144416A1 publication Critical patent/EP0144416A1/en
Ceased legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D17/00—Separation of liquids, not provided for elsewhere, e.g. by thermal diffusion
    • B01D17/02—Separation of non-miscible liquids
    • B01D17/0202—Separation of non-miscible liquids by ab- or adsorption
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/02—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography
    • 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
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C02F1/281—Treatment of water, waste water, or sewage by sorption using inorganic sorbents

Definitions

  • the present invention relates to a method for reducing the hydrocarbon content in air or water.
  • organic substances especially hydrocarbons, that have proved to be injurious to nature and human beings are various solvents used in paint-spraying and printing processes, chlorinated hydrocarbons from cleaning processes, chlorinated compounds obtained as by-products in various production processes, by-products in various combustion processes and production processes etc.
  • the technique which has been utilised most widely so far is based on adsorption with activated carbon as adsorbent, air or water being caused to pass through a filter' comprising the activated carbon which may be present in the form of a bed or have been applied to a carrier, such as paper or a ceramic material.
  • the activated carbon may also be present in the form of a fluidised bed, in which case the air or the water to be treated constitutes the fluidising agent.
  • the activated carbon has been used for a long time, and its advantages in the purification of air and water are well known. In spite of the fact that these known methods have been developed in the course of time towards increasingly better methods, they still suffer from certain disadvantages that could net be surmounted. Thus, the activated carbon has a low efficiency at low impurity concentrations. Furthermore, it is combustible and does not bear high temperatures, for which reason its regenerability is very limited after adsorption of high-boiling molecules. Furthermore, it is a "dirty" material, the handling of which evokes some aversion.
  • the use of different polymers as adsorbents has been discussed for quite some time.
  • the properties of the polymers are similar to those of the activated carbon, such as their adsorption capacity and their broad usefulness for a number of different adsorbable types of molecules.
  • they also have many of the disadvantages of the activated carbon, such as being combustible and susceptible to temperatures,
  • the object of this invention to provide a method of reducing the hydrocarbon content in air or water.
  • the method according to the invention is characterised in that the air or the water is caused to pass through a filter comprising a hydrophobic crystalline zeolite.
  • the zeolites used in the context of this invention have been made hydrophobic by giving them a high Si:Al ratio, either by direct synthesis or by modification of zeolites having a lower Si:Al ratio.
  • a normal zeolite is hydrophilic in character and adsorbs water vapour in preference to organic molecules.
  • By direct synthesis or by chemical modification of existing zeolites it is possible to obtain zeolites which are hydrophobic or lipophilic so that their tendency to adsorb organic molecules is increased. Because of their crystalline structures, these zeolites are capable of selectively adsorbing such substances as phenols, guaiacols, various solvents, degreasing agents, products from biochemical processes etc. from air or water, the dimensions of the crystalline structures determining the selective properties, primarily in respect of the size of the adsorbed molecules.
  • the zeolites used in the context of this invention are crystalline materials consisting of silicon, aluminium and oxygen and, optionally, simple cations, such as sodium or hydrogen ions. They are not combustible and bear heating to 800-900°C, which means that they can be subjected to regeneration processes under inclement conditions. Furthermore, the hydrophobic zeolites can be treated with mineral acids and thereby be freed from particle coatings.
  • the crystal structures are selective in respect of the molecules that can be adsorbed. In other words, they function as inverted sieves, i.e. they adsorb molecules up to a given size which is determined by the crystalline structure concerned, whereas the larger molecules are allowed to pass.
  • the zeolites may be hydrophobated gradually from the state in which they have entirely hydrophilic characteristics until they become entirely hydrophobic, which means that the hydrophobicity can be set to a value suitable for the type of molecules to be adsorbed.
  • Zeolites suitable for hydrophobation in this invention are heulandite, mordenite, phillipsite, chabazite, natrolite, analcite, clinoptilolite, gmelinite and/or faujasite.
  • the zeolites which so far have proved to be efficient are those having a ratio of Si:Al which is higher than 15:1, in particular HAISi 35 O 72 and HAlSi 25 O 52 .
  • the present invention is applicable to different uses, such as to the removal of relatively low contents of toxic substances, especially organic substances, from water. Furthermore, it may be used for removing toxic substances, especially such as are formed upon the combustion of fuels, from air introduced into motor vehicles, ships or buildings. Finally, the method can be used also for reducing the content of toxic substances in air discharged over densely populated areas.
  • the filters can be installed in different ways in inlet and outlet ducts. For example, a number of filter cartridges can be mounted in a collective housing for purifying contaminated water. When the filters have become more or less saturated with impurities, they are regenerated by admission of hot air or inert gas. After this regeneration, the solvents can then be recovered by condensation.
  • Butanol was prepared by a continuous chemical fermentation process. When the butanol content had reached 2.8%, the process stopped because the alcohol content became too high for the microorganism. By allowing the process water to pass through a hydrophobic zeolite having the composition HAISi 35 O 72 , the alcohol content was reduced and could be maintained at a constant level of 0.2%. The butanol was adsorbed continuously by the zeolite, and the process solution therefore did not reach the butanol concentrations toxic to the microorganisms. When the zeolite was saturated with butanol, it was replaced by a new batch of zeolite, and the butanol was recovered from the saturated zeolite. EXAMPLE 2
  • Waste water from the alkaline bleaching of papermaking pulp with low contents of chlorophenols and chloroguaiacols and high contents of methanol and formic acid was treated after pH adjustment with hydrophobic zeolite having the composition HAlSi 35 O 72 .
  • the content of chlorophenols and chloroguaiacols was reduced by about 35%, which content refers to the proportion of such compounds having kinetic diameters of less than about 8A.
  • Waste water from the chlorine bleaching of papermaking pulp with low contents of chlorophenols and chloroguaiacols and high contents of formic acid and methanol was treated directly with hydrophobic zeolite having the composition HAlSi 35 O 72 .
  • the content of solvents was reduced by about 30%, which content refers to the proportion of such compounds having kinetic diameters, of less than about 8A.
  • Exhaust air from a spray-painting booth containing 200 mg solvent per m 3 , primarily xylene and white spirit, was treated with a hydrophobic zeolite having the composition HAlSi 35 O 72 . The solvent content was reduced to 1 mg per m of air. The adsorbed amount of solvent was then distilled off and recovered from the zeolite.
  • Example 6 Exhaust air containing 2800 mg solvent per m 3 of air from a spray-painting booth was treated with a hydrophobic zeolite having the composition HAISi 35 O 72 . The solvent content in the treated air was decreased to about 1.5 mg per m 3 . The adsorbed amount was distilled off and recovered from the zeolite.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Hydrology & Water Resources (AREA)
  • General Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Organic Chemistry (AREA)
  • Analytical Chemistry (AREA)
  • Thermal Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Inorganic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Treating Waste Gases (AREA)
  • Gas Separation By Absorption (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

On réduit la teneur en hydrocarbures de l'air ou de l'eau en faisant passer l'air ou l'eau à travers un filtre comportant un zéolithe cristallin hydrophobe.The hydrocarbon content of the air or water is reduced by passing the air or water through a filter comprising a hydrophobic crystalline zeolite.

Description

METHOD FOR REDUCING THE HYDROCARBON CONTENT IN AIR OR WATER
The present invention relates to a method for reducing the hydrocarbon content in air or water.
In recent years, more and more attention has been given to the discharge into air and water of organic substances from different types of industries. This discharge frequently has an injurious effect on human beings and animals, but even though the injurious effects of some types of discharge may as yet be unknown, it is nevertheless desired to reduce the content of organic substances discharged into nature.
Examples of organic substances, especially hydrocarbons, that have proved to be injurious to nature and human beings are various solvents used in paint-spraying and printing processes, chlorinated hydrocarbons from cleaning processes, chlorinated compounds obtained as by-products in various production processes, by-products in various combustion processes and production processes etc.
The technique which has been utilised most widely so far is based on adsorption with activated carbon as adsorbent, air or water being caused to pass through a filter' comprising the activated carbon which may be present in the form of a bed or have been applied to a carrier, such as paper or a ceramic material. The activated carbon may also be present in the form of a fluidised bed, in which case the air or the water to be treated constitutes the fluidising agent.
The activated carbon has been used for a long time, and its advantages in the purification of air and water are well known. In spite of the fact that these known methods have been developed in the course of time towards increasingly better methods, they still suffer from certain disadvantages that could net be surmounted. Thus, the activated carbon has a low efficiency at low impurity concentrations. Furthermore, it is combustible and does not bear high temperatures, for which reason its regenerability is very limited after adsorption of high-boiling molecules. Furthermore, it is a "dirty" material, the handling of which evokes some aversion.
In addition to the use of activated carbon, the use of different polymers as adsorbents has been discussed for quite some time. In many respects, the properties of the polymers are similar to those of the activated carbon, such as their adsorption capacity and their broad usefulness for a number of different adsorbable types of molecules. On the other hand, they also have many of the disadvantages of the activated carbon, such as being combustible and susceptible to temperatures,
The disadvantages of the adsorbents hitherto employed are highly important to the usefulness of these adsorbents, for which reason one is anxious to find new and more efficient methods for purifying air and water from hydrocarbons.
It therefore is the object of this invention to provide a method of reducing the hydrocarbon content in air or water. The method according to the invention is characterised in that the air or the water is caused to pass through a filter comprising a hydrophobic crystalline zeolite.
The zeolites used in the context of this invention have been made hydrophobic by giving them a high Si:Al ratio, either by direct synthesis or by modification of zeolites having a lower Si:Al ratio.
A normal zeolite is hydrophilic in character and adsorbs water vapour in preference to organic molecules. By direct synthesis or by chemical modification of existing zeolites, it is possible to obtain zeolites which are hydrophobic or lipophilic so that their tendency to adsorb organic molecules is increased. Because of their crystalline structures, these zeolites are capable of selectively adsorbing such substances as phenols, guaiacols, various solvents, degreasing agents, products from biochemical processes etc. from air or water, the dimensions of the crystalline structures determining the selective properties, primarily in respect of the size of the adsorbed molecules.
The zeolites used in the context of this invention are crystalline materials consisting of silicon, aluminium and oxygen and, optionally, simple cations, such as sodium or hydrogen ions. They are not combustible and bear heating to 800-900°C, which means that they can be subjected to regeneration processes under inclement conditions. Furthermore, the hydrophobic zeolites can be treated with mineral acids and thereby be freed from particle coatings.
Since the crystal structures exactly define the pore size and the pore openings, they are selective in respect of the molecules that can be adsorbed. In other words, they function as inverted sieves, i.e. they adsorb molecules up to a given size which is determined by the crystalline structure concerned, whereas the larger molecules are allowed to pass. The zeolites may be hydrophobated gradually from the state in which they have entirely hydrophilic characteristics until they become entirely hydrophobic, which means that the hydrophobicity can be set to a value suitable for the type of molecules to be adsorbed. Zeolites suitable for hydrophobation in this invention are heulandite, mordenite, phillipsite, chabazite, natrolite, analcite, clinoptilolite, gmelinite and/or faujasite.
Among the zeolites which so far have proved to be efficient are those having a ratio of Si:Al which is higher than 15:1, in particular HAISi35O72 and HAlSi25O52. The present invention is applicable to different uses, such as to the removal of relatively low contents of toxic substances, especially organic substances, from water. Furthermore, it may be used for removing toxic substances, especially such as are formed upon the combustion of fuels, from air introduced into motor vehicles, ships or buildings. Finally, the method can be used also for reducing the content of toxic substances in air discharged over densely populated areas. The filters can be installed in different ways in inlet and outlet ducts. For example, a number of filter cartridges can be mounted in a collective housing for purifying contaminated water. When the filters have become more or less saturated with impurities, they are regenerated by admission of hot air or inert gas. After this regeneration, the solvents can then be recovered by condensation.
It is also possible to provide for filtration by having two parallel filter systems which are used alternatingly, one for filtration and the other for regeneration.
The invention will be described in more detail below with reference to the following Examples which in no way are intended to restrict the invention. EXAMPLE 1
Butanol was prepared by a continuous chemical fermentation process. When the butanol content had reached 2.8%, the process stopped because the alcohol content became too high for the microorganism. By allowing the process water to pass through a hydrophobic zeolite having the composition HAISi35O72, the alcohol content was reduced and could be maintained at a constant level of 0.2%. The butanol was adsorbed continuously by the zeolite, and the process solution therefore did not reach the butanol concentrations toxic to the microorganisms. When the zeolite was saturated with butanol, it was replaced by a new batch of zeolite, and the butanol was recovered from the saturated zeolite. EXAMPLE 2
Industrial waste water having a phenol content of 3% was allowed to pass through a regenerable filter consisting of a hydrophobic zeolite having the composition HAlSi25O52. In tnis manner, the phenol content was reduced to 0.01%. EXAMPLE 3
Waste water from the alkaline bleaching of papermaking pulp with low contents of chlorophenols and chloroguaiacols and high contents of methanol and formic acid was treated after pH adjustment with hydrophobic zeolite having the composition HAlSi35O72. The content of chlorophenols and chloroguaiacols was reduced by about 35%, which content refers to the proportion of such compounds having kinetic diameters of less than about 8A. EXAMPLE 4
Waste water from the chlorine bleaching of papermaking pulp with low contents of chlorophenols and chloroguaiacols and high contents of formic acid and methanol was treated directly with hydrophobic zeolite having the composition HAlSi35O72. The content of solvents was reduced by about 30%, which content refers to the proportion of such compounds having kinetic diameters, of less than about 8A. EXAMPLE 5
Exhaust air from a spray-painting booth, containing 200 mg solvent per m3, primarily xylene and white spirit, was treated with a hydrophobic zeolite having the composition HAlSi35O72. The solvent content was reduced to 1 mg per m of air. The adsorbed amount of solvent was then distilled off and recovered from the zeolite. Example 6 Exhaust air containing 2800 mg solvent per m3 of air from a spray-painting booth was treated with a hydrophobic zeolite having the composition HAISi35O72. The solvent content in the treated air was decreased to about 1.5 mg per m3. The adsorbed amount was distilled off and recovered from the zeolite.

Claims

1. A method for reducing the hydrocarbon content in air or water, c h a r a c t e r i s e d in that the air or the water is caused to pass through a filter comprising a hydrophobic crystalline zeolite.
2. A method as claimed in claim 1, c h a r a c t e r i s e d in that the hydrophobic crystalline zeolite is a. zeolite having a high Si:Al ratio.
3. A method as claimed in claim 2, c h a r a c t e r i s e d in that the zeolite is derived from heulandite, mordenite, phillipsite, chabazite, natrolite, analcite, clinoptilolite, gmelinite and/or faujasite.
4. A method as claimed in claim 1, c h a r a c t e r i s e d in that the zeolite has a Si:Al ratio higher than 15:1.
5. A method as claimed in claim 1, c h a r a c t e r i s e d in that the zeolite is HAlSi35O72 or HAlSi25O52.
EP19840902471 1983-06-09 1984-06-07 Method for reducing the hydrocarbon content in air or water Ceased EP0144416A1 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
SE8303268 1983-06-09
SE8303268A SE8303268D0 (en) 1983-06-09 1983-06-09 SET TO REMOVE TOXIC SUBSTANCES, SPECIFIC ORGANIC WATERS
SE8402393 1984-05-03
SE8402393A SE8402393D0 (en) 1983-06-09 1984-05-03 SET TO CLEAN AIR AND WATER FROM THE CALVET

Publications (1)

Publication Number Publication Date
EP0144416A1 true EP0144416A1 (en) 1985-06-19

Family

ID=26658505

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19840902471 Ceased EP0144416A1 (en) 1983-06-09 1984-06-07 Method for reducing the hydrocarbon content in air or water

Country Status (5)

Country Link
EP (1) EP0144416A1 (en)
DK (1) DK56485D0 (en)
FI (1) FI82611C (en)
SE (1) SE8402393D0 (en)
WO (1) WO1984004913A1 (en)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4648977A (en) * 1985-12-30 1987-03-10 Union Carbide Corporation Process for removing toxic organic materials from weak aqueous solutions thereof
SE456087B (en) * 1986-03-13 1988-09-05 Anox Ab APPLICATION OF A HYDROPHOBIC ZEOLITE MATERIAL AS ADSORPTION MATERIAL FOR BIOLOGICAL CLEANING OF THE WASTE WATER
CA2002012A1 (en) * 1989-07-03 1991-01-03 Jack L. Liston Method and apparatus for absorbing petroleum based products
US5256385A (en) * 1990-12-13 1993-10-26 Tosoh Corporation Adsorbent and cleaning method of waste gas containing ketonic organic solvents
US5676914A (en) * 1994-04-26 1997-10-14 Competitive Technologies, Inc. Method for the destruction of methylene iodide
US5445742A (en) * 1994-05-23 1995-08-29 Dow Corning Corporation Process for purifying halosilanes
US6120584A (en) * 1997-01-31 2000-09-19 Takasago Thermal Engineering Co., Ltd. Air cleaning apparatus, air filter and method for manufacturing the same
FR2807027B1 (en) * 2000-03-31 2002-05-31 Inst Francais Du Petrole PROCESS FOR PRODUCING PURIFIED WATER AND HYDROCARBONS FROM FOSSIL RESOURCES
EP1813577B1 (en) 2004-11-05 2017-01-04 Hitachi, Ltd. Method and apparatus for removing organic substance from oily water from oilfield
US20060102000A1 (en) 2004-11-17 2006-05-18 Daewoo Electronics Corporation Wet type air cleaner
WO2010012656A1 (en) * 2008-07-31 2010-02-04 Shell Internationale Research Maatschappij B.V. Process for separating liquid mixtures
EP2168656A1 (en) * 2008-09-30 2010-03-31 Sued-Chemie AG Recovery and purification process for organic molecules

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5497592A (en) * 1978-01-20 1979-08-01 Asahi Chem Ind Co Ltd Improved zeolite adsorber and its manufacture and uses
CA1131195A (en) * 1978-02-23 1982-09-07 David E. Earls Ultrahydrophobic zeolite y

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8404913A1 *

Also Published As

Publication number Publication date
DK56485A (en) 1985-02-07
FI850529A0 (en) 1985-02-08
WO1984004913A1 (en) 1984-12-20
DK56485D0 (en) 1985-02-07
FI850529L (en) 1985-02-08
SE8402393D0 (en) 1984-05-03
FI82611B (en) 1990-12-31
FI82611C (en) 1991-04-10

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