CA1200627A - Process for solvent extraction using phosphine oxide mixtures - Google Patents
Process for solvent extraction using phosphine oxide mixturesInfo
- Publication number
- CA1200627A CA1200627A CA000432929A CA432929A CA1200627A CA 1200627 A CA1200627 A CA 1200627A CA 000432929 A CA000432929 A CA 000432929A CA 432929 A CA432929 A CA 432929A CA 1200627 A CA1200627 A CA 1200627A
- Authority
- CA
- Canada
- Prior art keywords
- phosphine oxide
- oxide
- carbon atoms
- process according
- phosphine
- 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
Links
- AUONHKJOIZSQGR-UHFFFAOYSA-N oxophosphane Chemical compound P=O AUONHKJOIZSQGR-UHFFFAOYSA-N 0.000 title claims abstract description 31
- 239000000203 mixture Substances 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims abstract description 24
- 230000008569 process Effects 0.000 title claims abstract description 21
- 238000000638 solvent extraction Methods 0.000 title description 2
- 125000004432 carbon atom Chemical group C* 0.000 claims abstract description 16
- 239000007864 aqueous solution Substances 0.000 claims abstract description 15
- MPQXHAGKBWFSNV-UHFFFAOYSA-N oxidophosphanium Chemical class [PH3]=O MPQXHAGKBWFSNV-UHFFFAOYSA-N 0.000 claims abstract description 12
- 150000002894 organic compounds Chemical class 0.000 claims abstract description 9
- 230000002378 acidificating effect Effects 0.000 claims abstract description 8
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 36
- ZMBHCYHQLYEYDV-UHFFFAOYSA-N trioctylphosphine oxide Chemical group CCCCCCCCP(=O)(CCCCCCCC)CCCCCCCC ZMBHCYHQLYEYDV-UHFFFAOYSA-N 0.000 claims description 35
- PPDZLUVUQQGIOJ-UHFFFAOYSA-N 1-dihexylphosphorylhexane Chemical compound CCCCCCP(=O)(CCCCCC)CCCCCC PPDZLUVUQQGIOJ-UHFFFAOYSA-N 0.000 claims description 16
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 claims description 14
- 230000008018 melting Effects 0.000 claims description 11
- 238000002844 melting Methods 0.000 claims description 11
- 150000001735 carboxylic acids Chemical class 0.000 claims description 9
- 125000000217 alkyl group Chemical group 0.000 claims description 6
- XBDQKXXYIPTUBI-UHFFFAOYSA-N dimethylselenoniopropionate Natural products CCC(O)=O XBDQKXXYIPTUBI-UHFFFAOYSA-N 0.000 claims description 6
- 150000002989 phenols Chemical class 0.000 claims description 6
- 125000003710 aryl alkyl group Chemical group 0.000 claims description 4
- 125000000753 cycloalkyl group Chemical group 0.000 claims description 4
- 235000019260 propionic acid Nutrition 0.000 claims description 3
- IUVKMZGDUIUOCP-BTNSXGMBSA-N quinbolone Chemical compound O([C@H]1CC[C@H]2[C@H]3[C@@H]([C@]4(C=CC(=O)C=C4CC3)C)CC[C@@]21C)C1=CCCC1 IUVKMZGDUIUOCP-BTNSXGMBSA-N 0.000 claims description 3
- 239000002904 solvent Substances 0.000 description 23
- 238000011084 recovery Methods 0.000 description 10
- 150000001875 compounds Chemical class 0.000 description 9
- 239000003085 diluting agent Substances 0.000 description 9
- 239000000243 solution Substances 0.000 description 7
- 238000000605 extraction Methods 0.000 description 6
- 239000008346 aqueous phase Substances 0.000 description 5
- 239000012074 organic phase Substances 0.000 description 5
- 239000002253 acid Substances 0.000 description 4
- 150000007513 acids Chemical class 0.000 description 4
- 239000002440 industrial waste Substances 0.000 description 3
- 239000012071 phase Substances 0.000 description 3
- NKTOLZVEWDHZMU-UHFFFAOYSA-N 2,5-xylenol Chemical compound CC1=CC=C(C)C(O)=C1 NKTOLZVEWDHZMU-UHFFFAOYSA-N 0.000 description 2
- JWAZRIHNYRIHIV-UHFFFAOYSA-N 2-naphthol Chemical compound C1=CC=CC2=CC(O)=CC=C21 JWAZRIHNYRIHIV-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 239000004305 biphenyl Substances 0.000 description 2
- 235000010290 biphenyl Nutrition 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- -1 l-naphthol Chemical compound 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 230000007257 malfunction Effects 0.000 description 2
- IWDCLRJOBJJRNH-UHFFFAOYSA-N p-cresol Chemical compound CC1=CC=C(O)C=C1 IWDCLRJOBJJRNH-UHFFFAOYSA-N 0.000 description 2
- ZUOUZKKEUPVFJK-UHFFFAOYSA-N phenylbenzene Natural products C1=CC=CC=C1C1=CC=CC=C1 ZUOUZKKEUPVFJK-UHFFFAOYSA-N 0.000 description 2
- WQGWDDDVZFFDIG-UHFFFAOYSA-N pyrogallol Chemical class OC1=CC=CC(O)=C1O WQGWDDDVZFFDIG-UHFFFAOYSA-N 0.000 description 2
- GHMLBKRAJCXXBS-UHFFFAOYSA-N resorcinol Chemical compound OC1=CC=CC(O)=C1 GHMLBKRAJCXXBS-UHFFFAOYSA-N 0.000 description 2
- XNKICCFGYSXSAI-UHFFFAOYSA-N 1,1-diphenylpropan-2-amine Chemical compound C=1C=CC=CC=1C(C(N)C)C1=CC=CC=C1 XNKICCFGYSXSAI-UHFFFAOYSA-N 0.000 description 1
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N 1,4-Benzenediol Natural products OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 description 1
- WWYUQXYAGXKBNE-UHFFFAOYSA-N 1-[bis(2,4,4-trimethylpentyl)phosphoryl]-2,4,4-trimethylpentane Chemical compound CC(C)(C)CC(C)CP(=O)(CC(C)CC(C)(C)C)CC(C)CC(C)(C)C WWYUQXYAGXKBNE-UHFFFAOYSA-N 0.000 description 1
- FTKKDUVZLDDBEN-UHFFFAOYSA-N 1-[ethyl(octyl)phosphoryl]octane Chemical compound CCCCCCCCP(=O)(CC)CCCCCCCC FTKKDUVZLDDBEN-UHFFFAOYSA-N 0.000 description 1
- MSKVTMZQUUEALA-UHFFFAOYSA-N 1-[hexyl(2-methylpropyl)phosphoryl]hexane Chemical compound CCCCCCP(=O)(CC(C)C)CCCCCC MSKVTMZQUUEALA-UHFFFAOYSA-N 0.000 description 1
- BRLCBJSJAACAFG-UHFFFAOYSA-N 1-didodecylphosphoryldodecane Chemical compound CCCCCCCCCCCCP(=O)(CCCCCCCCCCCC)CCCCCCCCCCCC BRLCBJSJAACAFG-UHFFFAOYSA-N 0.000 description 1
- XHOHEJRYAPSRPZ-UHFFFAOYSA-N 1-dioctadecylphosphoryloctadecane Chemical compound CCCCCCCCCCCCCCCCCCP(=O)(CCCCCCCCCCCCCCCCCC)CCCCCCCCCCCCCCCCCC XHOHEJRYAPSRPZ-UHFFFAOYSA-N 0.000 description 1
- QWBBPBRQALCEIZ-UHFFFAOYSA-N 2,3-dimethylphenol Chemical compound CC1=CC=CC(O)=C1C QWBBPBRQALCEIZ-UHFFFAOYSA-N 0.000 description 1
- KUFFULVDNCHOFZ-UHFFFAOYSA-N 2,4-xylenol Chemical compound CC1=CC=C(O)C(C)=C1 KUFFULVDNCHOFZ-UHFFFAOYSA-N 0.000 description 1
- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 description 1
- RKJGHINMWRVRJW-UHFFFAOYSA-N 3-[bis(2-ethylhexyl)phosphorylmethyl]heptane Chemical compound CCCCC(CC)CP(=O)(CC(CC)CCCC)CC(CC)CCCC RKJGHINMWRVRJW-UHFFFAOYSA-N 0.000 description 1
- TVEXGJYMHHTVKP-UHFFFAOYSA-N 6-oxabicyclo[3.2.1]oct-3-en-7-one Chemical compound C1C2C(=O)OC1C=CC2 TVEXGJYMHHTVKP-UHFFFAOYSA-N 0.000 description 1
- ORAORDAXVMRVIX-UHFFFAOYSA-N 9-octyl-9$l^{5}-phosphabicyclo[3.3.1]nonane 9-oxide Chemical compound C1CCC2CCCC1P2(=O)CCCCCCCC ORAORDAXVMRVIX-UHFFFAOYSA-N 0.000 description 1
- JPYHHZQJCSQRJY-UHFFFAOYSA-N Phloroglucinol Chemical class CCC=CCC=CCC=CCC=CCCCCC(=O)C1=C(O)C=C(O)C=C1O JPYHHZQJCSQRJY-UHFFFAOYSA-N 0.000 description 1
- 241000022563 Rema Species 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 125000003545 alkoxy group Chemical group 0.000 description 1
- 229940058344 antitrematodals organophosphorous compound Drugs 0.000 description 1
- 229910052785 arsenic Inorganic materials 0.000 description 1
- 229950011260 betanaphthol Drugs 0.000 description 1
- 125000006267 biphenyl group Chemical group 0.000 description 1
- ANTSCNMPPGJYLG-UHFFFAOYSA-N chlordiazepoxide Chemical compound O=N=1CC(NC)=NC2=CC=C(Cl)C=C2C=1C1=CC=CC=C1 ANTSCNMPPGJYLG-UHFFFAOYSA-N 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 125000004093 cyano group Chemical group *C#N 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000994 depressogenic effect Effects 0.000 description 1
- RDLZJCXTAYHYHX-UHFFFAOYSA-N dibenzylphosphorylmethylbenzene Chemical compound C=1C=CC=CC=1CP(CC=1C=CC=CC=1)(=O)CC1=CC=CC=C1 RDLZJCXTAYHYHX-UHFFFAOYSA-N 0.000 description 1
- AOAUYBZIBQRSBZ-UHFFFAOYSA-N dihexylphosphorylmethylbenzene Chemical compound CCCCCCP(=O)(CCCCCC)CC1=CC=CC=C1 AOAUYBZIBQRSBZ-UHFFFAOYSA-N 0.000 description 1
- SZAQMRYDICITOU-UHFFFAOYSA-N dioctylphosphorylmethylbenzene Chemical compound CCCCCCCCP(=O)(CCCCCCCC)CC1=CC=CC=C1 SZAQMRYDICITOU-UHFFFAOYSA-N 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 239000000374 eutectic mixture Substances 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 238000002309 gasification Methods 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 150000002367 halogens Chemical class 0.000 description 1
- FUZZWVXGSFPDMH-UHFFFAOYSA-N hexanoic acid group Chemical group C(CCCCC)(=O)O FUZZWVXGSFPDMH-UHFFFAOYSA-N 0.000 description 1
- 229960004337 hydroquinone Drugs 0.000 description 1
- 125000000687 hydroquinonyl group Chemical class C1(O)=C(C=C(O)C=C1)* 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000003295 industrial effluent Substances 0.000 description 1
- 150000002484 inorganic compounds Chemical class 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 150000002576 ketones Chemical class 0.000 description 1
- 150000002689 maleic acids Chemical class 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 150000002903 organophosphorus compounds Chemical class 0.000 description 1
- NQPDZGIKBAWPEJ-UHFFFAOYSA-N pentanoic acid group Chemical class C(CCCC)(=O)O NQPDZGIKBAWPEJ-UHFFFAOYSA-N 0.000 description 1
- 239000005011 phenolic resin Substances 0.000 description 1
- 229920001568 phenolic resin Polymers 0.000 description 1
- QCDYQQDYXPDABM-UHFFFAOYSA-N phloroglucinol Chemical class OC1=CC(O)=CC(O)=C1 QCDYQQDYXPDABM-UHFFFAOYSA-N 0.000 description 1
- 229960001553 phloroglucinol Drugs 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 229940079877 pyrogallol Drugs 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
Classifications
-
- 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
- C02F1/26—Treatment of water, waste water, or sewage by extraction
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D11/00—Solvent extraction
- B01D11/04—Solvent extraction of solutions which are liquid
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
- C07F9/00—Compounds containing elements of Groups 5 or 15 of the Periodic Table
- C07F9/02—Phosphorus compounds
- C07F9/28—Phosphorus compounds with one or more P—C bonds
- C07F9/50—Organo-phosphines
- C07F9/53—Organo-phosphine oxides; Organo-phosphine thioxides
- C07F9/5304—Acyclic saturated phosphine oxides or thioxides
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Molecular Biology (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Extraction Or Liquid Replacement (AREA)
- Physical Water Treatments (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Abstract of the Disclosure A process for the removal of difficult-to-remove acidic organic compounds from aqueous solutions using novel phosphine oxide mixtures in which mixtures at least two phosphine oxides are present, the total number of carbon atoms in a first oxide being at least 15 and the difference in the total number of carbon atoms in the first and second oxides being at least 2, at least one said phosphine oxide being present in an amount of at least 5% by weight and not more than 60% by weight. Unexpectedly high extractability is achieved using the mixtures.
Description
~Z~ 27 The present invention relates to the removal of acidic or~anic compounds from aqueous solution and in particular to the use of phosphine oxide mixtures of two or more such oxides without the use of a diluent for the removal of lower carboxylic acids and phenolic compounds from commercial effluent.
~ he treatment of aqueous effluent for removal of contami-nants and also the recovery of valuable compounds ~rom solution is a most essential part of modern chemical plants. A number of pro-cedures are used such as steam-stripping and the somewhat more complicated solvent extraction, the latter technique being largely dependent upon the properties o~ the compounds to be recovered.
The choice of solvent is critical and solvent loss must be mini-mized.
Some organic compounds such as acetic acid and phenol in dilute aqueous solu-tions are particularly difficult to remove. It is known to extract acetic acid using esters or ketones as solvent.
However, the e~uilibrium distribution coefficient, Kd (weight fraction of solute in solvent phase/weight fraction in aqueous phase, at e~uilibrium) for acetic acid with these solvents is about 1.0 or less. This low Kd necessitates relatively hi~h solvent flow E~es .in the extraction process and recovery wi-th these solvents .is not economically attractive when -there is less -than 3 -to 5 wt%
o~ a~.id in the aqueous solution.
Alternative, and somewhat improved solvent systems have been obtained by the use of certain organophosphorous compounds and in particular phosphine oxides in a diluent. These extractant/
diluent systems are disadvanta~eous, however, since the presence of 06~:7 a diluent (which is often necessary in order that hi~her melting point extractants can be used) effectively reduces tlle concentra-tion of extractant and also hinders subsequent stripping operations by volatilizing concurrently with the compound which has been removed from aqueous solution.
The use of 100% extractant as solvent withou~ -the use of a diluent is therefore desirable but is limited by the melting point of the extractant and the economic operating temperatures at which removal is conducted. In particular -the use of neat tri-L0 alkylphosphine oxides is known but their relatively high meltingpoints require that the removal operation be carried out at above ambient temperatures thus incurring the risk of freeze up during plant malfunction.
It has now been unexpectedly discovered that by use of trialkylphosphine oxides mixtures, not only is the melting point at a more acceptable level but that the ability of the mixture to extract acidic organic compounds from dilute aqueous solutions i5 high. The mixtures provide unexpectedly high extraction coeffi-cients for weakl~ extracted compounds such as acetic acid. The ~0 or~anic phase with removed compound can be stripped using several me~hods such as distillation or stripping with an alkali solution.
Thus, according to the present invention, there is prov.ided a process for removing an acidic organic compound selected ~rom the group consisting of a substituted or unsubstituted car-boxylic acid having one to five carbon atoms and a substituted or unsubstituted phenolic compound from a dilute aqueous solution which comprises contacting said aqueous solution with a mixture of
~ he treatment of aqueous effluent for removal of contami-nants and also the recovery of valuable compounds ~rom solution is a most essential part of modern chemical plants. A number of pro-cedures are used such as steam-stripping and the somewhat more complicated solvent extraction, the latter technique being largely dependent upon the properties o~ the compounds to be recovered.
The choice of solvent is critical and solvent loss must be mini-mized.
Some organic compounds such as acetic acid and phenol in dilute aqueous solu-tions are particularly difficult to remove. It is known to extract acetic acid using esters or ketones as solvent.
However, the e~uilibrium distribution coefficient, Kd (weight fraction of solute in solvent phase/weight fraction in aqueous phase, at e~uilibrium) for acetic acid with these solvents is about 1.0 or less. This low Kd necessitates relatively hi~h solvent flow E~es .in the extraction process and recovery wi-th these solvents .is not economically attractive when -there is less -than 3 -to 5 wt%
o~ a~.id in the aqueous solution.
Alternative, and somewhat improved solvent systems have been obtained by the use of certain organophosphorous compounds and in particular phosphine oxides in a diluent. These extractant/
diluent systems are disadvanta~eous, however, since the presence of 06~:7 a diluent (which is often necessary in order that hi~her melting point extractants can be used) effectively reduces tlle concentra-tion of extractant and also hinders subsequent stripping operations by volatilizing concurrently with the compound which has been removed from aqueous solution.
The use of 100% extractant as solvent withou~ -the use of a diluent is therefore desirable but is limited by the melting point of the extractant and the economic operating temperatures at which removal is conducted. In particular -the use of neat tri-L0 alkylphosphine oxides is known but their relatively high meltingpoints require that the removal operation be carried out at above ambient temperatures thus incurring the risk of freeze up during plant malfunction.
It has now been unexpectedly discovered that by use of trialkylphosphine oxides mixtures, not only is the melting point at a more acceptable level but that the ability of the mixture to extract acidic organic compounds from dilute aqueous solutions i5 high. The mixtures provide unexpectedly high extraction coeffi-cients for weakl~ extracted compounds such as acetic acid. The ~0 or~anic phase with removed compound can be stripped using several me~hods such as distillation or stripping with an alkali solution.
Thus, according to the present invention, there is prov.ided a process for removing an acidic organic compound selected ~rom the group consisting of a substituted or unsubstituted car-boxylic acid having one to five carbon atoms and a substituted or unsubstituted phenolic compound from a dilute aqueous solution which comprises contacting said aqueous solution with a mixture of
2 -~2~ 7 at least two phosphine oxides, where a first phosphine oxide has the formula:
R
\
R2 P = O
and a second phosphine oxide has the formula:
Rl \
/
R3 ~
wherein Rl R2 R3, Ri R2 and R3 are individually selected from the group consisting of alkyl, cycloalkyl, aralkyl and substituted aralkyl, each having C4 - C18, and the total number of carbon atoms in said first phosphine oxide is at least 15, and the total number of carbon atoms in said ~econd phosphine oxide is at least 17, the difference in the total number of carbon atoms in the first and second oxides being at least 2, at least one said phosphine oxide being present in an amount of at least 5% by weight and not more than 60~ by weight.
PreEerably, the total number of carbon atoms in said second phosphine oxide is at least 19 and the diE:Eerence in the total number of carbon atoms in the Eirst and second oxides i9 at least 4.
More preferably at least one phosphine oxide is present in amount of between about 25-45 wt% and said mixtures of phosphine oxide has a melting point below about 50C.
While the process of the present invention is believed to ~2(~6~7 be useful with a variety of valuable pollutants or impurities in dilute aqueous streams, it is particularly useful for acidic organic compounds such as carboxylic acids and phenolic compounds.
In particular the process is used for removing carboxylic acids having one to five carbon atoms, preferably acetic, propionic, butyric and valeric acids (commonly found in industrial effluents) and also phenol. The carboxylic acids may be substituted by one or more halogen, hydroxyl, cyano or alkoxyl groups. Other specific acids which may be removed by the process of the present invention are exemplified by hexanoic, heptanedoic, octanoic, nonanoic, benæoi.c, succinic, oxalic, malic, lactic, cyanoacetic, glycolic, ~nd maleic acids. Phenolic compounds subjec~ to the instant invention include those substituted by one or more alkyl groups.
Examples of phenolic compounds which can be removed from dilute aqueous streams include p-cresol, resorcinol, l-naphthol, 2-naph-thol, o-, m- and p-xylenol and unsubstituted or substituted hydroquinone, phloroglucinol and pyrogallol~
The compound or compounds removed from dilute a~ueous solution can be present in any low or moderately low amount in the ~0 dilute solution, although usually in an amount less than 5wt~ arld more likely less than 2wt% or even lwt%.
The process of the present invention is particularly useful for the recovery of carboxylic acids from paper mill and synthetic fuel oil plants effluents. The process is also valuable for the recovery of phenol from phenolic resin production effluent and in coal gasification. It is believed that the recovery of organic and inorganic compounds which are only normally weakly extractable (e.g. Sb, As, Bi compounds) can be carried out by the ~Z~6~7 process of the present invention.
In the phosphine oxides, when one or more R groups are alkyl, preferred alkyls include about C4 to about C18 straight and branched chain alkyls while preferred cycloalkyls include six carbon to eight carbon substituted or unsubstituted cycloalkyls.
Examples of suitable phosphine oxides include, but are not limited to, tri-n-hexylphosphine oxide (THPO), tri-n-octyl-phosphine oxide (TOPO), tris(2,4,4-trimethylpentyl)-phosphine oxide, ~ricyclohexylphosphine oxide, tri-n-dodecylphosphine oxide, L0 tri-n-octadecylphosphine oxide, tris(2-ethylhexyl)phosphine oxide, di-n-octylethylphosphine oxide, di-n-hexylisobutylphosphine oxide, octyldiisobutylphosphine oxide, tribenzylphosphine oxide, di-n-hexylbenzylphosphine oxide, di-n-octylbenzylphosphine oxide, 9-octyl-9-phosphabicyclo[3.3.1]nonane-9-oxide, and the like. TOPO
and THPO are preferred oxides in a two part mix.
While one oxide should be present in an amount of at least Swt~ and not more than 60wt%, a preferred amount is between about 25-~5 wt% and more preferably about 35wt%. Although a number of phosphine oxides can be used in the mixture, it is most ~0 conve~ient to use a two part mix. A particularly preferred two p~rt mix is tri-n-octyl-phosphine oxide (TOPO) toge-ther with tri-n-hexyl-phosphine oxide (THPO) the preferred ratio for the TOPO/THPO
mix-t~lre is 35/65 wt~. However a synergistic effect to give unex-pectedly increased Kd values may be obtained with two or more part mixes of the above named phosphine oxide.
The phosphine oxides used in the mixture are selected so that the difference in the total number of carbon atoms in the 6~7 first and second oxides is at least 2, and preferably at least 4 and more preferably 6 or 8.
Preferably the melting point of the mixture is below about 60C which is the usual upper temperature a~ which commercial e~fluent solutions are treated by liquid/liquid extraction pro-cesses. However, it is desirable that the melting point be lower in order to improve the e~ficiency and costs of the process. A
melting point of about 50C is preferable and thus a phosphine oxide mix melting below about 50C, and more preferably 30C or 25C, will from a practical viewpoint be selected for use in the process provided its ability to extract the acidic organic compound is acceptable. The most preferred mixture of TOPO/THPO in a 35/65 wt% ratio melts at about 15C.
Apart from the energy savings obtainable by the use of a low melting point phosphine oxide mixture, other advantages of low m.p. mixtures include the avoidance of diluent to be used so that the phosphine oxides can be used neat, and also the avoidance of the possibility of freeze up during plant malfunction. The low m.p. eutectic mixture of phosphine oxides also permits, by virtue Of depressed m.p. phosphine oxides to be used which previously could only be used at increased temperatures or together with a ~lluent, the latter use frequently complicatin~ subsequent strip pin~ operations.
~ owever, the principal advantage of the phosphine oxide mixtures used in the process of the present invention is the unexpectedly increased extractability provided by such mixtures.
This extractability exceeds that of an equal amount of 6~7 one phosphine oxide when used alone and thus provides for opera-tional savings in amount of phosphine oxide required to extract a desired solute from dilute aqueous solution.
The present invention will now be described in more detail with reference to examples provided by way of illustration only.
Example 1 Samples of solvent were tested for extractibility of acetic acid and also phenol from dilute aqueous solution. Each solvent sample was shaken and mixed with a fixed amount of aqueous solution containing acetic acid. After several minutes the aqueous phase and organic phase were allowed to separate and the aqueous phase analysed for acetic acid presence. The procedure was repeated with the aqueous phase until all acetic acid had been recovered and passed into the organic phase. The amount, by volume, or organic phase (solvent) required for 100% recovery is indic~ted by the aqueous/organic (A/O) ra-tio.
Acetic Acid (Commercial Efluent~
A/O ~or Sample Solvent 100% Recovery 1 150 gpl TOPO in DPA o.5 2 ~00 gpl TOPO in DPA 0.66
R
\
R2 P = O
and a second phosphine oxide has the formula:
Rl \
/
R3 ~
wherein Rl R2 R3, Ri R2 and R3 are individually selected from the group consisting of alkyl, cycloalkyl, aralkyl and substituted aralkyl, each having C4 - C18, and the total number of carbon atoms in said first phosphine oxide is at least 15, and the total number of carbon atoms in said ~econd phosphine oxide is at least 17, the difference in the total number of carbon atoms in the first and second oxides being at least 2, at least one said phosphine oxide being present in an amount of at least 5% by weight and not more than 60~ by weight.
PreEerably, the total number of carbon atoms in said second phosphine oxide is at least 19 and the diE:Eerence in the total number of carbon atoms in the Eirst and second oxides i9 at least 4.
More preferably at least one phosphine oxide is present in amount of between about 25-45 wt% and said mixtures of phosphine oxide has a melting point below about 50C.
While the process of the present invention is believed to ~2(~6~7 be useful with a variety of valuable pollutants or impurities in dilute aqueous streams, it is particularly useful for acidic organic compounds such as carboxylic acids and phenolic compounds.
In particular the process is used for removing carboxylic acids having one to five carbon atoms, preferably acetic, propionic, butyric and valeric acids (commonly found in industrial effluents) and also phenol. The carboxylic acids may be substituted by one or more halogen, hydroxyl, cyano or alkoxyl groups. Other specific acids which may be removed by the process of the present invention are exemplified by hexanoic, heptanedoic, octanoic, nonanoic, benæoi.c, succinic, oxalic, malic, lactic, cyanoacetic, glycolic, ~nd maleic acids. Phenolic compounds subjec~ to the instant invention include those substituted by one or more alkyl groups.
Examples of phenolic compounds which can be removed from dilute aqueous streams include p-cresol, resorcinol, l-naphthol, 2-naph-thol, o-, m- and p-xylenol and unsubstituted or substituted hydroquinone, phloroglucinol and pyrogallol~
The compound or compounds removed from dilute a~ueous solution can be present in any low or moderately low amount in the ~0 dilute solution, although usually in an amount less than 5wt~ arld more likely less than 2wt% or even lwt%.
The process of the present invention is particularly useful for the recovery of carboxylic acids from paper mill and synthetic fuel oil plants effluents. The process is also valuable for the recovery of phenol from phenolic resin production effluent and in coal gasification. It is believed that the recovery of organic and inorganic compounds which are only normally weakly extractable (e.g. Sb, As, Bi compounds) can be carried out by the ~Z~6~7 process of the present invention.
In the phosphine oxides, when one or more R groups are alkyl, preferred alkyls include about C4 to about C18 straight and branched chain alkyls while preferred cycloalkyls include six carbon to eight carbon substituted or unsubstituted cycloalkyls.
Examples of suitable phosphine oxides include, but are not limited to, tri-n-hexylphosphine oxide (THPO), tri-n-octyl-phosphine oxide (TOPO), tris(2,4,4-trimethylpentyl)-phosphine oxide, ~ricyclohexylphosphine oxide, tri-n-dodecylphosphine oxide, L0 tri-n-octadecylphosphine oxide, tris(2-ethylhexyl)phosphine oxide, di-n-octylethylphosphine oxide, di-n-hexylisobutylphosphine oxide, octyldiisobutylphosphine oxide, tribenzylphosphine oxide, di-n-hexylbenzylphosphine oxide, di-n-octylbenzylphosphine oxide, 9-octyl-9-phosphabicyclo[3.3.1]nonane-9-oxide, and the like. TOPO
and THPO are preferred oxides in a two part mix.
While one oxide should be present in an amount of at least Swt~ and not more than 60wt%, a preferred amount is between about 25-~5 wt% and more preferably about 35wt%. Although a number of phosphine oxides can be used in the mixture, it is most ~0 conve~ient to use a two part mix. A particularly preferred two p~rt mix is tri-n-octyl-phosphine oxide (TOPO) toge-ther with tri-n-hexyl-phosphine oxide (THPO) the preferred ratio for the TOPO/THPO
mix-t~lre is 35/65 wt~. However a synergistic effect to give unex-pectedly increased Kd values may be obtained with two or more part mixes of the above named phosphine oxide.
The phosphine oxides used in the mixture are selected so that the difference in the total number of carbon atoms in the 6~7 first and second oxides is at least 2, and preferably at least 4 and more preferably 6 or 8.
Preferably the melting point of the mixture is below about 60C which is the usual upper temperature a~ which commercial e~fluent solutions are treated by liquid/liquid extraction pro-cesses. However, it is desirable that the melting point be lower in order to improve the e~ficiency and costs of the process. A
melting point of about 50C is preferable and thus a phosphine oxide mix melting below about 50C, and more preferably 30C or 25C, will from a practical viewpoint be selected for use in the process provided its ability to extract the acidic organic compound is acceptable. The most preferred mixture of TOPO/THPO in a 35/65 wt% ratio melts at about 15C.
Apart from the energy savings obtainable by the use of a low melting point phosphine oxide mixture, other advantages of low m.p. mixtures include the avoidance of diluent to be used so that the phosphine oxides can be used neat, and also the avoidance of the possibility of freeze up during plant malfunction. The low m.p. eutectic mixture of phosphine oxides also permits, by virtue Of depressed m.p. phosphine oxides to be used which previously could only be used at increased temperatures or together with a ~lluent, the latter use frequently complicatin~ subsequent strip pin~ operations.
~ owever, the principal advantage of the phosphine oxide mixtures used in the process of the present invention is the unexpectedly increased extractability provided by such mixtures.
This extractability exceeds that of an equal amount of 6~7 one phosphine oxide when used alone and thus provides for opera-tional savings in amount of phosphine oxide required to extract a desired solute from dilute aqueous solution.
The present invention will now be described in more detail with reference to examples provided by way of illustration only.
Example 1 Samples of solvent were tested for extractibility of acetic acid and also phenol from dilute aqueous solution. Each solvent sample was shaken and mixed with a fixed amount of aqueous solution containing acetic acid. After several minutes the aqueous phase and organic phase were allowed to separate and the aqueous phase analysed for acetic acid presence. The procedure was repeated with the aqueous phase until all acetic acid had been recovered and passed into the organic phase. The amount, by volume, or organic phase (solvent) required for 100% recovery is indic~ted by the aqueous/organic (A/O) ra-tio.
Acetic Acid (Commercial Efluent~
A/O ~or Sample Solvent 100% Recovery 1 150 gpl TOPO in DPA o.5 2 ~00 gpl TOPO in DPA 0.66
3 THPO/TOPO (65/35 wt% ratio) 2.0 Phenol (Synthetic Solution) A/O for Sample Solvent 100% Recovery 1 100 gpl TOPO in Conoco 500 2 2 200 gpl TOPO in Conoco 500 3 3 325 gpl TOPO in Conoco 500 5
4 THPO/TOPO ( 65/35 wt% ratio) 10 Thus in samples 1 and 2, TOPO was dissolved in D.P.A., a commercial diluent supplied by Conoco which is formed of diphenyl ~lkanes, and it can be seen that an increased amount of TOPO in the solvent requires less organic phase to be used, i.e. the aqueous/
organic (A/O) ratio is increased. However, in solvent sample 3, the phosphine oxide mixture (65 wt% : 35 w~% of THPO:TOPO) gives substantially increased ability to extract the acetic acid. Also, in the phenol extraction, sample 4 ~ives a substantially increased A/O value thereby clearly indicating that less organic (solvent) phase is necessary for 100% recovery o~ phenol from the aqueous solution.
Example 2 An aqueous commercial waste effluent containin~ acetic ana propionic acid in an amount of 6.15 and 1.50 gpl was extrac-ted us.in~ a THPO/TOPO mixture. The equilibrium concentration for each o~ ~he c~rboxylic acids was measured for different ~/O ratios.
~24~2~
Table 1 Carboxylic Acid Extraction from Commercial Waste Effluent which includes Acetic and Propionic Acid Solvent (wt%) : 65 THPO, 35 TOPO
Temperature : 50C
Equilibrium Concentration (gpl)*
Acetic - Propionic A/O Org. Aq. KD Org. ' Aq. KD
518.3 2.50 7.3 6.150.27 22.8 29.70 1.30 7.5 2.780.11 25.3 15.54 0.61 g.l 1.470.03 49.0 *Based on aqueous analysis and mass balance.
Isotherms for rema;n;ng acids in co-incidence with the Y axis.
Additionally, the same effluent was extracted using solvent containing different concentrations of TOPO.
Table 2 Carboxylic Acid Extraction from Commercial Waste Effluent Using 150 and 400 gpl TOPO Solvents Temperature : 50C
Diluent : DPA
Equi;libr~ium ~Gon;cen;t~r;a;ti;on;;(gpl;)*
'A'c'e'-t'icPropionic Solv~nt A/O Org.Aq. KD ~ ~ KD
150 ~pl TOPO 2 3.~0 4.20 0.9 l.g0 n.60 3.0 .in DP~ 1 3.452.70 1.3 1.150.35 3.3 400 ~pl TOPO 2 5.10 2.60 2.0 2.53 0.24 10.5 in DPA 1 4.701.45 3.2 1.400.10 14.0 *Based on aqueous analysis and mass balance.
Isotherms for other acids essentially co-incident with the Y axis It is clearly demonstrated that Kd values for the THPO/
TOPO mixture are far in excess of the Kd values for the TOPO alone in a diphenyl alkane (DPA) diluent, for corresponding A/O ratios.
Example 3 An aqueous solution containing 10 gpl phenol was extrac-ted with solvents having different extractant concen~rations.
Table 3 Phenol Recovery The Effect of Extractant Concentration Solvents : (1) 100 gpl TOPO in Conoco 500 (2) 200 gpl TOPO in Conoco 500 (3) 325 gpl TOPO in Conoco 500 (4) 65 w/o THPO, 35 w/o TOPO
Aqueous : 10 gpl Phenol (nominal) Solution Temperature : 50C
Equi;librium Phenol Con~.(;gpl) 100 gpl TOPO 200 gpl TOPO 325 gpl TOPO THPO/TOPO
~/0 ~ Aq. KD Oxg. A~. KD Org. A~ KD Org. A~ KD
1 10.1 0.10 101 9.84 0.04 246 10.5 0.04 262 9.93 0.02 497 2 19.~ 0.47 41 19.6 0.10 196 20.9 0.08 260 19.8 0.03 660
organic (A/O) ratio is increased. However, in solvent sample 3, the phosphine oxide mixture (65 wt% : 35 w~% of THPO:TOPO) gives substantially increased ability to extract the acetic acid. Also, in the phenol extraction, sample 4 ~ives a substantially increased A/O value thereby clearly indicating that less organic (solvent) phase is necessary for 100% recovery o~ phenol from the aqueous solution.
Example 2 An aqueous commercial waste effluent containin~ acetic ana propionic acid in an amount of 6.15 and 1.50 gpl was extrac-ted us.in~ a THPO/TOPO mixture. The equilibrium concentration for each o~ ~he c~rboxylic acids was measured for different ~/O ratios.
~24~2~
Table 1 Carboxylic Acid Extraction from Commercial Waste Effluent which includes Acetic and Propionic Acid Solvent (wt%) : 65 THPO, 35 TOPO
Temperature : 50C
Equilibrium Concentration (gpl)*
Acetic - Propionic A/O Org. Aq. KD Org. ' Aq. KD
518.3 2.50 7.3 6.150.27 22.8 29.70 1.30 7.5 2.780.11 25.3 15.54 0.61 g.l 1.470.03 49.0 *Based on aqueous analysis and mass balance.
Isotherms for rema;n;ng acids in co-incidence with the Y axis.
Additionally, the same effluent was extracted using solvent containing different concentrations of TOPO.
Table 2 Carboxylic Acid Extraction from Commercial Waste Effluent Using 150 and 400 gpl TOPO Solvents Temperature : 50C
Diluent : DPA
Equi;libr~ium ~Gon;cen;t~r;a;ti;on;;(gpl;)*
'A'c'e'-t'icPropionic Solv~nt A/O Org.Aq. KD ~ ~ KD
150 ~pl TOPO 2 3.~0 4.20 0.9 l.g0 n.60 3.0 .in DP~ 1 3.452.70 1.3 1.150.35 3.3 400 ~pl TOPO 2 5.10 2.60 2.0 2.53 0.24 10.5 in DPA 1 4.701.45 3.2 1.400.10 14.0 *Based on aqueous analysis and mass balance.
Isotherms for other acids essentially co-incident with the Y axis It is clearly demonstrated that Kd values for the THPO/
TOPO mixture are far in excess of the Kd values for the TOPO alone in a diphenyl alkane (DPA) diluent, for corresponding A/O ratios.
Example 3 An aqueous solution containing 10 gpl phenol was extrac-ted with solvents having different extractant concen~rations.
Table 3 Phenol Recovery The Effect of Extractant Concentration Solvents : (1) 100 gpl TOPO in Conoco 500 (2) 200 gpl TOPO in Conoco 500 (3) 325 gpl TOPO in Conoco 500 (4) 65 w/o THPO, 35 w/o TOPO
Aqueous : 10 gpl Phenol (nominal) Solution Temperature : 50C
Equi;librium Phenol Con~.(;gpl) 100 gpl TOPO 200 gpl TOPO 325 gpl TOPO THPO/TOPO
~/0 ~ Aq. KD Oxg. A~. KD Org. A~ KD Org. A~ KD
1 10.1 0.10 101 9.84 0.04 246 10.5 0.04 262 9.93 0.02 497 2 19.~ 0.47 41 19.6 0.10 196 20.9 0.08 260 19.8 0.03 660
5 3~.3 3.3~ 10 45.0 0.87 5~ - - - 49.4 0.07 706 The equilibrium phenol concentrations in the organic and aqueous phases for various A/O values was determined and the equi-librium distribution coefficient, Kd calculated. Again it can beseen that the Kd values for the phosphine oxide mixture is unexpec-tedly higher than the single oxlde solvents, for all A/O values.
`:
`:
Claims (9)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for removing an acidic organic compound selec-ted from the group consisting of a substituted or unsubstituted carboxylic acid having one to five carbon atoms and a substituted or unsubstituted phenolic compound from a dilute aqueous solution which comprises contacting said aqueous solution with a mixture of at least two phosphine oxides, where a first phosphine oxide has the formula:
and a second phosphine oxide has the formula:
wherein R1 R2 R3, R1 R2 and R3 are individually selected from the group consisting of alkyl, cycloalkyl, aralkyl and substituted aralkyl, each having C4 - C18, and the total number of carbon atoms in said first phosphine oxide is at least 15, and the total number of carbon atoms in said second phosphine oxide is at least 17, the difference in the total number of carbon atoms in the first and second oxides being at least 2, at least one said phos-phine oxide being present in an amount of at least 5% by weight and not more than 60% by weight.
and a second phosphine oxide has the formula:
wherein R1 R2 R3, R1 R2 and R3 are individually selected from the group consisting of alkyl, cycloalkyl, aralkyl and substituted aralkyl, each having C4 - C18, and the total number of carbon atoms in said first phosphine oxide is at least 15, and the total number of carbon atoms in said second phosphine oxide is at least 17, the difference in the total number of carbon atoms in the first and second oxides being at least 2, at least one said phos-phine oxide being present in an amount of at least 5% by weight and not more than 60% by weight.
2. A process according to claim 1 wherein the total number of carbon atoms in said second phosphine oxide is at least 19 and the difference in the total number of carbon atoms in the first and second oxides is at least 4.
3. A process according to claim 1 wherein said at least one phosphine oxide is present in amount of between about 25-45 wt%.
4. A process according to claim 1 or 3 wherein said mixtures of phosphine oxide has a melting point below about 50°C.
5. A process according to claim 1 wherein said acidic organic compound is selected from the group consisting of acetic acid, propionic acid and phenol.
6. A process according to claim 1 wherein said at least one phosphine oxide is present in an amount of about 35 wt%.
7. A process according to claim 1 or 3 wherein said mixture of phosphine oxide has a melting point below about 30°C.
8. A process according to claim 1 wherein said at least one phosphine oxide is tri-n-octyl-phosphine oxide.
9. A process according to claim 3 or 5 wherein said mixture of phosphine oxides is tri-n-hexylphosphine oxide and tri-n-octyl phosphine oxide.
Priority Applications (10)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000432929A CA1200627A (en) | 1983-07-21 | 1983-07-21 | Process for solvent extraction using phosphine oxide mixtures |
| EP84108117A EP0132700B1 (en) | 1983-07-21 | 1984-07-11 | Liquid phosphine oxide systems for solvent extraction |
| AT84108117T ATE33617T1 (en) | 1983-07-21 | 1984-07-11 | LIQUID SYSTEMS OF PHOSPHINE OXIDES FOR SOLVENT EXTRACTION. |
| DE8484108117T DE3470517D1 (en) | 1983-07-21 | 1984-07-11 | Liquid phosphine oxide systems for solvent extraction |
| JP59149773A JPS6041591A (en) | 1983-07-21 | 1984-07-20 | Method of extracting solvent by using phosphine oxide |
| YU128984A YU45902B (en) | 1983-07-21 | 1984-07-20 | PROCESS FOR PREPARING A PHOSPHIN OXIDE MIXTURE |
| FI842933A FI75498C (en) | 1983-07-21 | 1984-07-20 | Solvent extraction process using phosphine oxide mixtures, phosphine oxide mixtures used in the process and preparation thereof. |
| NO842984A NO842984L (en) | 1983-07-21 | 1984-07-20 | PROCEDURE AND MEDICINE FOR AA REMOVE ACID ORGANIC COMPOUNDS FROM Aqueous SOLUTIONS |
| ZA845643A ZA845643B (en) | 1983-07-21 | 1984-07-20 | Liquid phosphine oxide systems for solvent extraction |
| BR8403631A BR8403631A (en) | 1983-07-21 | 1984-07-20 | EXTRACTION PROCESS WITH SOLVENT, MIXING OF PHOSPHINE OXIDE AND PROCESS FOR ITS PREPARATION |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000432929A CA1200627A (en) | 1983-07-21 | 1983-07-21 | Process for solvent extraction using phosphine oxide mixtures |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1200627A true CA1200627A (en) | 1986-02-11 |
Family
ID=4125723
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000432929A Expired CA1200627A (en) | 1983-07-21 | 1983-07-21 | Process for solvent extraction using phosphine oxide mixtures |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JPS6041591A (en) |
| CA (1) | CA1200627A (en) |
| ZA (1) | ZA845643B (en) |
-
1983
- 1983-07-21 CA CA000432929A patent/CA1200627A/en not_active Expired
-
1984
- 1984-07-20 ZA ZA845643A patent/ZA845643B/en unknown
- 1984-07-20 JP JP59149773A patent/JPS6041591A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0439397B2 (en) | 1992-06-29 |
| ZA845643B (en) | 1985-03-27 |
| JPS6041591A (en) | 1985-03-05 |
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