CA1049045A - Removal of mineral acid catalyst from cumene hydroperoxide cleavage products - Google Patents
Removal of mineral acid catalyst from cumene hydroperoxide cleavage productsInfo
- Publication number
- CA1049045A CA1049045A CA75222338A CA222338A CA1049045A CA 1049045 A CA1049045 A CA 1049045A CA 75222338 A CA75222338 A CA 75222338A CA 222338 A CA222338 A CA 222338A CA 1049045 A CA1049045 A CA 1049045A
- Authority
- CA
- Canada
- Prior art keywords
- alkali metal
- zone
- inorganic salt
- acid
- phenate
- 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.)
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The mineral acid catalyst is removed from the prod-ucts of cumene hydroperoxide cleavage by contact with an aqueous solution of an inorganic salt and an excess of an alkali metal hydroxide or phenate in a first zone. Suitably the aqueous solution contains so-dium sulphate and sodium hydroxide or phenate. The aqueous layer is removed and the organic layer con-tacted in a second zone with an aqueous solution com-prising an inorganic salt and sufficient weak acid to decompose any phenate carried over from the first zone. Suitable weak acids are oxalic and citric acids but the preferred acid is carbonic acid formed 'in situ' by passing carbondioxide into the aqueous inorganic salt solution.
Description
~049045 The preoent in ontlon relateo generally to 8 proc-oo for the protuction of phenol by tho ositation Or cu~ene and ~inoral acld -catalyoed cles~s6e Or cu~ene hydroperoslae. In p rtlcul r it rolat-o to the ro~oval and neutralloatlon of mineral acid catalyot and by-proauot organlc aoldo fro~ the clea~age products The productlon Or phenol by the o~idation Or cumene follo~ d br the uineral aoid-oatalyoed clea~age Or cu~one hydroporoslde lo ~ell-kno~n. ~he cleavage product contsino phenol and acetono ae th principal producte togethor ~ith ~arying a~ounto of oid~-producto ln the for~ of taro and organic subotancoa ouch ae organlc acido. E~for-the producte can bo recoverod lt lo neceeoary to romovo and noutralleo the ~ineral acid catalyot and pr~fersbly the or6anic acldo in th cloa~a6e producto oince tho prooonce Or tho acido ln the ouboequent diotlllatlon interrereo ~ith the f~iclont roco~ery of the produoto and by-producto of the roactlon ln addltion to cauoin6 corroolon of th dlotillation oquip~ent Hithertoforo thie hao b--n aohi- n d, for esa~plo, by treatlng the cl-a~age producto ~ith an aquooua oolutlon o2 an lnorganlc oalt to estract the acldo and pro~ote phao- oo p ratlon and an aqueouo oolutlon of an alkall metal hydroslde or phonate to neutralloo th aclde. Inoompleto r~o~al of the oalto at thlo otago or tho for~tlon of an oscooo of al~li metal phonate reoults in thoir pao d n6 in tho organio phaoe, either in oolution or o w pension, to tho aeparation and purlrication atagee ~here their prooenoe loado to foullng of dlotlllatlon colu~n robolloro and produot ylola 1008-particularly damagin6 oalt in this reopect is oodlum phenate ~hich may be lntroduc-d in ord-r to n-utralloo both tho mlnoral acld catalyot and tho organlc acid by-products, thoroby liborating phenol, or may be formod by the reaction of osooss caustic ooda, added as a n-utralioing agent, and phonol undor alkalino conditions Tho salts concentrato in the tar residues ro~o~od from variow point~ in tho proco~o and
2 - ~
O
~049045 eventually appear as ash when the tars are burnedO HiBh inorganic ash contents render the residual tar unsuitable for use as fuel oil to con-ventional boilers. In the past the tendency has been to attempt to maintain the p~l slightly below 7.0 during the catalyst removal and neutralisation step in order to prevent alkali metal phenate being carried over to the subsequent washing stepO In practice however difficulties are experienced during commercial operation in maintaining the pH slightly below 7.0 resulting in the aforementioned disadvantages. Moreover even if the pH
is successfully maintained below 7.0 it is sometimes found that chemical losses, e.gO loss of methylstyrene, occur under acid conditionsO
The present invention substantially overcomes the aforementioned disadvantages of the prior art by providing a process whereby the mineral acid catalyst and at least part of the organic acid by-products are removed and neutralised in such a manner that the cleavage products are not con-taminated with undesirable quantities of inorganic or organic salts.
Accordingly the present invention is a process for the removal and neutralisation of mineral acid catalyst and organic acid by-products from the reaction mixture resulting from mineral acid catalysed cumene hydroperoxide cleavage which process comprises contacting at a temperature below about 50C said reaction mixture in a first zone with an aqueous solution comprising an inorganic salt selected from alkali metal sulphates, ammonium sulphate, alkali metal chloride, ammonium chloride, alkali metal phosphates, ammonium phosphates, alkali metal nitrates and ammonium nitrate and an excess of alkali metal hydroxide or phenate sufficient to neutralise said mineral acid and organic acid by-products and to maintain the pH of the aqueous phase between 7 and 9 whereby said acids are extracted from the organic phase into the aqueous phase and neutralised therein, separating said aqueous phase containing the neutralised acids therefrom, then con-tacting at a temperature of from about 10 to 60C said organic phase in a second zone with an aqueous solution comprising an inorganic salt selected from alkali metal sulphates, ammonium sulphate, alkali metal chlorides, ammonium chloride, alkali metal phosphates, ammonium phosphate, alkali metal ~; ~ - 3 -nitrates and ammonium nitrate and a weak acid selected from the group con-sisting of carbonic acid, citric acid and oxalic acid in an amount sufficient to decompose alkali metal phenate -.
carrlea ovor from the flrat ~one and th-reafter a-psratlng th- aqueoua phs~e thorofro~.
The inorganlo ~alt w ed ln tho flr~t snt seoond zonea may b~
any ~ater-soluble cslt 8uitsble aalt~ lncludo slksll metal ~ulphatea 8uch ss soalum snd potsaBlum 8ulphate; s~conlu~ sulphst~; the alksll metsl chlorldes such as sodlu~ snd potaselum chlorlde; a~monlum ¢hlorlde; snd the alkali metal snd smmonlum phosphstes snd nltrstea.
~owe~er lt i~ proferred to use 8 ~alt ln whlch the snlon corroaponda to the snion of the mlneral acid cstslyet u~ed in the clesvsge resctlon and the cation correspondo to the cation of the sIkall motsl co~pound uaed for neutralisation of the s¢id Thus when ~ulphuric acid i8 the mlnersl scid snd sodiu~ hydro~ide or ~odium phenste the alkali metsl hydroside or phenate the preferred inor6snic sslt is ~odlum aulphste In general concentratlons of from about 0 5~0 up to sbout 50% by ~elght csn be employed depending on th- p rtioulsr sslt snd tempersture in uae.
With ~odium ~ulphste for eIample B concontrstion bet~e n sbout 0.5 and 30~0 by ~elght and prerersbly of about 15 to 25% by ~elght at about 40 to 45C lo sultable for the romo~sl Or aulphurlc acid The alkall metal hydroside addod to the flrat zone to n-utrsllse the mlneral aoid cstalyst and the orgsnic acid by-produote ia prof~rsbly sodlum hydroslde ~ltornatively sodium phenste msy be added to the flrst zone Tho aodium phenste may bo thst ~odlum phenste resulting from the estrsction of phenol from acetophenone at 8 lster stsge ln the phenol-from-cumen~-hydroporo~ido proc-ss ,~queoua alksll metal ; hydroside or phenst- aolution may be added to the Sirst zone sepsrately or co~lnod ~ith aqueow inorganlc salt solutlon. It is preS~rred to comblne the two solutlons.
The amount of alkali metal hydrosido or alkall metal phonato added to the fir~t zone must be greater thsn the atolohlometrlc quantlty requlrod to neutrallJe the mineral scid catalyat and tho organlc acld by-protucta but 19 preferably only ou~flclent to aintaln th-in the range 7 to 9 The e~traction and neutralioation of th- acide in th- flr~t zone may be e~feoted at any temperature up to about 50C, though in general temperatureo of about 35 to 45C are preferred. Th- upp~r restrlctlon on the temperature range is impooed by the de~irability of avoiaing plant corrosion and of a~oiding precipitation of oalt.
In addition to removlng mineral acid oataly~t in the rirst ~on the treatment ~ith an aqueo w solution comprioing an inorganic ~alt and escees of alkali metal hydroside or aIksli metal phenate also removes at least part of the organic acids preoent in the cleavage products, in the form of their alkali metal oalto.
The acid contacted ~ith the organic phase in the ~econd zon-is preferably a ~eak acid By ~ea~ acid ~ithin the oont-st of th present applicatlon lo meant an acid of lnsuffielent ~trength to eau~-corroslon of the plant and one ~hlch does not ¢ontamlnat- the organio phaoe ~lth by-producto. Sultable acldo include o~allc acld and cltrlo acld. The pr-ferred acld i8 carbonlc acid ~hlch may b for~ed ~ln ~ltu' by f--dlng oarbon dlo~lde to the oecond sone in the preo-nce of an aqu-ous ~olutlon o~ an lnorganic salt ln an amount ~u~ficlent to decompooe th- alkall metal phenate carrled over in the organio pha~e from the firot zon-The aqueouo solutlon of the inorganio salt used ln th o-oond son- may ~uitably be the aqueous phase separated from th flrot ~on .
It io preferred ho~-ver to remove a part of the separated aqueouo phas-$n a bleed stream ln order to remo~e oome of the oodium sslto of organic ; acids from the syst~.
Contsct of the aqueous solution ~ith the organlc phas- ln th oecond sone 18 suitably effected at ambient temperatur but sy be effected at any temperature in th- range 10 to about 60C , th- t-mp-- erature limit~ being dictated by the desirabillty of avoi~ing ~alt preoipitation.
,, .. .~
1049~45 The follo~ing E2ample illu~trate~ the proce~ of the ln~ ntion:-E2amDlo The products of the mineral acld catalysea clea~age of cu en-hydroperoside ~ero treated in a firgt zone with a 20% by weiBht aqueouo oolution of sodlum sulphate and sufficient aqueous ~odium hydrosite solution to completely neutralise the sulphuric acid catalyst and organic acid by-products in the cleavage product and make the p~
of the squeous solution in the first zone in the range 7 to a. The aqueous phase wns separated and the organic phase free from acid, eampled for ash content before being pasoed to a ~econd zone where it wa~
washed uith further aqueous sodium sulphate solution wlth simultaneoua passage of an esceso of carbon dloslde through the second zone. The aqueous phase was separated and the organic phase free from sulphuric acid, organic acids and sodium phenate tested for ash contont prior to further proceoslng. The results of tho ash content anslyooe for ~arying concentrations of aqueous sodium sulphate oolutiono uoed ~n the second zone are shown in the Table.
.
oolution in 2nd zone Diooolved ssh before Di~sol~ed soh sfter 20% by welght . 2nd wsoh (ppm) 2nd wash (ppm)*
0 emulsified-... . .
850 , 10
O
~049045 eventually appear as ash when the tars are burnedO HiBh inorganic ash contents render the residual tar unsuitable for use as fuel oil to con-ventional boilers. In the past the tendency has been to attempt to maintain the p~l slightly below 7.0 during the catalyst removal and neutralisation step in order to prevent alkali metal phenate being carried over to the subsequent washing stepO In practice however difficulties are experienced during commercial operation in maintaining the pH slightly below 7.0 resulting in the aforementioned disadvantages. Moreover even if the pH
is successfully maintained below 7.0 it is sometimes found that chemical losses, e.gO loss of methylstyrene, occur under acid conditionsO
The present invention substantially overcomes the aforementioned disadvantages of the prior art by providing a process whereby the mineral acid catalyst and at least part of the organic acid by-products are removed and neutralised in such a manner that the cleavage products are not con-taminated with undesirable quantities of inorganic or organic salts.
Accordingly the present invention is a process for the removal and neutralisation of mineral acid catalyst and organic acid by-products from the reaction mixture resulting from mineral acid catalysed cumene hydroperoxide cleavage which process comprises contacting at a temperature below about 50C said reaction mixture in a first zone with an aqueous solution comprising an inorganic salt selected from alkali metal sulphates, ammonium sulphate, alkali metal chloride, ammonium chloride, alkali metal phosphates, ammonium phosphates, alkali metal nitrates and ammonium nitrate and an excess of alkali metal hydroxide or phenate sufficient to neutralise said mineral acid and organic acid by-products and to maintain the pH of the aqueous phase between 7 and 9 whereby said acids are extracted from the organic phase into the aqueous phase and neutralised therein, separating said aqueous phase containing the neutralised acids therefrom, then con-tacting at a temperature of from about 10 to 60C said organic phase in a second zone with an aqueous solution comprising an inorganic salt selected from alkali metal sulphates, ammonium sulphate, alkali metal chlorides, ammonium chloride, alkali metal phosphates, ammonium phosphate, alkali metal ~; ~ - 3 -nitrates and ammonium nitrate and a weak acid selected from the group con-sisting of carbonic acid, citric acid and oxalic acid in an amount sufficient to decompose alkali metal phenate -.
carrlea ovor from the flrat ~one and th-reafter a-psratlng th- aqueoua phs~e thorofro~.
The inorganlo ~alt w ed ln tho flr~t snt seoond zonea may b~
any ~ater-soluble cslt 8uitsble aalt~ lncludo slksll metal ~ulphatea 8uch ss soalum snd potsaBlum 8ulphate; s~conlu~ sulphst~; the alksll metsl chlorldes such as sodlu~ snd potaselum chlorlde; a~monlum ¢hlorlde; snd the alkali metal snd smmonlum phosphstes snd nltrstea.
~owe~er lt i~ proferred to use 8 ~alt ln whlch the snlon corroaponda to the snion of the mlneral acid cstslyet u~ed in the clesvsge resctlon and the cation correspondo to the cation of the sIkall motsl co~pound uaed for neutralisation of the s¢id Thus when ~ulphuric acid i8 the mlnersl scid snd sodiu~ hydro~ide or ~odium phenste the alkali metsl hydroside or phenate the preferred inor6snic sslt is ~odlum aulphste In general concentratlons of from about 0 5~0 up to sbout 50% by ~elght csn be employed depending on th- p rtioulsr sslt snd tempersture in uae.
With ~odium ~ulphste for eIample B concontrstion bet~e n sbout 0.5 and 30~0 by ~elght and prerersbly of about 15 to 25% by ~elght at about 40 to 45C lo sultable for the romo~sl Or aulphurlc acid The alkall metal hydroside addod to the flrat zone to n-utrsllse the mlneral aoid cstalyst and the orgsnic acid by-produote ia prof~rsbly sodlum hydroslde ~ltornatively sodium phenste msy be added to the flrst zone Tho aodium phenste may bo thst ~odlum phenste resulting from the estrsction of phenol from acetophenone at 8 lster stsge ln the phenol-from-cumen~-hydroporo~ido proc-ss ,~queoua alksll metal ; hydroside or phenst- aolution may be added to the Sirst zone sepsrately or co~lnod ~ith aqueow inorganlc salt solutlon. It is preS~rred to comblne the two solutlons.
The amount of alkali metal hydrosido or alkall metal phonato added to the fir~t zone must be greater thsn the atolohlometrlc quantlty requlrod to neutrallJe the mineral scid catalyat and tho organlc acld by-protucta but 19 preferably only ou~flclent to aintaln th-in the range 7 to 9 The e~traction and neutralioation of th- acide in th- flr~t zone may be e~feoted at any temperature up to about 50C, though in general temperatureo of about 35 to 45C are preferred. Th- upp~r restrlctlon on the temperature range is impooed by the de~irability of avoiaing plant corrosion and of a~oiding precipitation of oalt.
In addition to removlng mineral acid oataly~t in the rirst ~on the treatment ~ith an aqueo w solution comprioing an inorganic ~alt and escees of alkali metal hydroside or aIksli metal phenate also removes at least part of the organic acids preoent in the cleavage products, in the form of their alkali metal oalto.
The acid contacted ~ith the organic phase in the ~econd zon-is preferably a ~eak acid By ~ea~ acid ~ithin the oont-st of th present applicatlon lo meant an acid of lnsuffielent ~trength to eau~-corroslon of the plant and one ~hlch does not ¢ontamlnat- the organio phaoe ~lth by-producto. Sultable acldo include o~allc acld and cltrlo acld. The pr-ferred acld i8 carbonlc acid ~hlch may b for~ed ~ln ~ltu' by f--dlng oarbon dlo~lde to the oecond sone in the preo-nce of an aqu-ous ~olutlon o~ an lnorganic salt ln an amount ~u~ficlent to decompooe th- alkall metal phenate carrled over in the organio pha~e from the firot zon-The aqueouo solutlon of the inorganio salt used ln th o-oond son- may ~uitably be the aqueous phase separated from th flrot ~on .
It io preferred ho~-ver to remove a part of the separated aqueouo phas-$n a bleed stream ln order to remo~e oome of the oodium sslto of organic ; acids from the syst~.
Contsct of the aqueous solution ~ith the organlc phas- ln th oecond sone 18 suitably effected at ambient temperatur but sy be effected at any temperature in th- range 10 to about 60C , th- t-mp-- erature limit~ being dictated by the desirabillty of avoi~ing ~alt preoipitation.
,, .. .~
1049~45 The follo~ing E2ample illu~trate~ the proce~ of the ln~ ntion:-E2amDlo The products of the mineral acld catalysea clea~age of cu en-hydroperoside ~ero treated in a firgt zone with a 20% by weiBht aqueouo oolution of sodlum sulphate and sufficient aqueous ~odium hydrosite solution to completely neutralise the sulphuric acid catalyst and organic acid by-products in the cleavage product and make the p~
of the squeous solution in the first zone in the range 7 to a. The aqueous phase wns separated and the organic phase free from acid, eampled for ash content before being pasoed to a ~econd zone where it wa~
washed uith further aqueous sodium sulphate solution wlth simultaneoua passage of an esceso of carbon dloslde through the second zone. The aqueous phase was separated and the organic phase free from sulphuric acid, organic acids and sodium phenate tested for ash contont prior to further proceoslng. The results of tho ash content anslyooe for ~arying concentrations of aqueous sodium sulphate oolutiono uoed ~n the second zone are shown in the Table.
.
oolution in 2nd zone Diooolved ssh before Di~sol~ed soh sfter 20% by welght . 2nd wsoh (ppm) 2nd wash (ppm)*
0 emulsified-... . .
850 , 10
3?0 25 *Ash contents were determined by lgnition.
The results ohow thst mineral acid cstalyst snd by-product organic acids are remo~ed from the oumene hydroperoside clea~sge product~
by the procoss o~ the in~ention without contaminsting the cleavage product with oubstsntial qu~ntitiee of re~idusl salts.
The results ohow thst mineral acid cstalyst snd by-product organic acids are remo~ed from the oumene hydroperoside clea~sge product~
by the procoss o~ the in~ention without contaminsting the cleavage product with oubstsntial qu~ntitiee of re~idusl salts.
Claims (8)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for the removal and neutralisation of mineral acid catalyst and organic acid by-products from the reaction mixture resulting from mineral acid catalysed cumene hydroperoxide cleavage which process comprises contacting at a temperature below about 50°C said reaction mixture in a first zone with an aqueous solution comprising an inorganic salt selected from alkali metal sulphates, ammonium sulphate, alkali metal chloride, ammonium chloride, alkali metal phosphates, ammonium phosphates, alkali metal nitrates and ammonium nitrate and an excess of alkali metal hydroxide or phenate sufficient to neutralise said mineral acid and organic acid by-products and to maintain the pH of the aqueous phase between 7 and 9 whereby said acids are extracted from the organic phase into the aqueous phase and neutralised therein, separating said aqueous phase containing the neutralised acids therefrom, then contacting at a temperature of from about 10 to 60°C said organic phase in a second zone with an aqueous solution comprising an inorganic salt selected from alkali metal sulphates, ammonium sulphate, alkali metal chlorides, ammonium chloride, alkali metal phosphates, ammonium phosphate, alkali metal nitrates and ammonium nitrate and a weak acid selected from the group consisting of carbonic acid, citric acid ant oxalic acid in an amount sufficient to decompose alkali metal phenate carried over from the first zone, and thereafter separating the aqueous phase there-from.
2. A process according to claim 1 wherein the concentration of the inorganic salt is in the range 0.5 to 50% by weight.
3. A process according to claim 1 wherein the inorganic salt is selected from sodium chloride, potassium chloride, ammonium chloride, sodium sulphate, potassium sulphate, ammonium sulphate, ammonium phosphate and ammonium nitrate.
4. A process according to claim 1 wherein the inorganic salt used in the first and second zones is a salt in which the anion corresponds to the anion of the mineral acid catalyst used in the cleavage reaction and the cation corresponds to the cation of the alkali metal hydroxide or phenate used for neutralisation of the acids.
5. A process according to claim 4 wherein the inorganic salt is sodium sulphate the concentration of which in the aqueous solution is in the range 0.5 to 30% by weight at a temperature in the range 40-45°C.
6. A process according to claim 1 wherein the alkali metal hydroxide or alkali metal phenate contacted with the reaction mixture in the first zone is sodium hydroxide or sodium phenate.
7. A process according to claim 1 wherein a combined aqueous solution of the inorganic salt and the alkali metal hydroxide or phenate is added to the first zone.
8. A process according to claim 1 wherein the carbonic acid is formed 'in situ' by feeding carbon dioxide to the second zone in the presence of an aqueous solution of an inorganic salt.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA75222338A CA1049045A (en) | 1975-03-18 | 1975-03-18 | Removal of mineral acid catalyst from cumene hydroperoxide cleavage products |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA75222338A CA1049045A (en) | 1975-03-18 | 1975-03-18 | Removal of mineral acid catalyst from cumene hydroperoxide cleavage products |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1049045A true CA1049045A (en) | 1979-02-20 |
Family
ID=4102563
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA75222338A Expired CA1049045A (en) | 1975-03-18 | 1975-03-18 | Removal of mineral acid catalyst from cumene hydroperoxide cleavage products |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1049045A (en) |
-
1975
- 1975-03-18 CA CA75222338A patent/CA1049045A/en not_active Expired
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