CA1038510A - Automated quantitative analysis of ionic species - Google Patents
Automated quantitative analysis of ionic speciesInfo
- Publication number
- CA1038510A CA1038510A CA229,416A CA229416A CA1038510A CA 1038510 A CA1038510 A CA 1038510A CA 229416 A CA229416 A CA 229416A CA 1038510 A CA1038510 A CA 1038510A
- Authority
- CA
- Canada
- Prior art keywords
- exchange resin
- ion
- column
- sample solution
- ion exchange
- 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
Landscapes
- Treatment Of Liquids With Adsorbents In General (AREA)
Abstract
ABSTRACT
Integrated system for quantitative analysis, using ion exchange resins, of ionic species, typically at a remote location, includes an eluant water reservoir, a sample injection valve, a pump delivering water to the sample injection valve, ion exchange resin means for ion separation with or without treatment for interfering ions or for total conversion of all ions by ion exchange to a single preselected ion pair, a conductivity cell with associated readout means, and clean-up resin bed means, all connected in series and in a closed loop, the clean-up resin bed means delivering deionized water to the water reservoir, means for delivering sample solution and standard solution, at mutually exclusive times, to the sample injection valve, and a computer-controller coordinating sample delivery and readout. Preferably means is provided for occasionally flushing the sample solution delivery system with a bactericide. The readout means may include a teletype or other means for transmitting the analysis results to a remote location.
Integrated system for quantitative analysis, using ion exchange resins, of ionic species, typically at a remote location, includes an eluant water reservoir, a sample injection valve, a pump delivering water to the sample injection valve, ion exchange resin means for ion separation with or without treatment for interfering ions or for total conversion of all ions by ion exchange to a single preselected ion pair, a conductivity cell with associated readout means, and clean-up resin bed means, all connected in series and in a closed loop, the clean-up resin bed means delivering deionized water to the water reservoir, means for delivering sample solution and standard solution, at mutually exclusive times, to the sample injection valve, and a computer-controller coordinating sample delivery and readout. Preferably means is provided for occasionally flushing the sample solution delivery system with a bactericide. The readout means may include a teletype or other means for transmitting the analysis results to a remote location.
Description
` ~38~;~11D
The invention relates to an integrated system for the automated quantitative analysis of one or more ionic species utilizing one or more ion exchange resin beds for separations or exchanges, with or without removal of înter- `~
fering ions, and detecting eluted ion species with a con~
ductivity cell. The invention more particularly relates to an integrated system for quantitative analysis of one or more . ;~
ionic species using water for elution of the sample from an ion exchange bed and recycling the water, after purification, ~ -for re-use.
There is a constant and ever increasing demand for a rapid, inexpensive method of analysis of large numbers of samples of, for example, surface waters, i.e., natural waters, boiler blow-down, and manufacturing p}ant efluents for total dissolved solids or a measure thereof, There is also a great need for simple automatable apparatus for carry-ing out such analysis as well as for analysis of process ~ streams for a specified single ion occurring alone except for i a plurality of countervalent ions, or, for analysis of a mixture of organic ca~boxylic acids or the carboxylate salts whether or not in admixture with soluble metal halides.
The determinations in each such case have generally , been carried out using old classical, slow, and relatively costly, methods. Even where ion exchange separations, chroma- - ~
' 25 tographically or by exchange, have been utilized, the fractions ~ ~ -:-, .
` obtained have generally been analyzed by classical methods or by methods which usually require a different test and/or a different instrument for each species to be determined.
Therefore, a new approach with new apparatus appears to be needed.
.
,, ~
~i16,820-F -1-... ,, . , . , .. , , , . , . , . . .. . .. . ~
The invention resides in an integrated system utilizing ion exchange resin means in automated analysis of a sample solution containing at least one ionic species to be quantitatively determined, which comprises~
a reservoir for eluant water; ~ ~:
-^ valve means for selecting a predetermined-sized :~
quantity of sample solution; ~ :
. hydraulic pressure means for deliv~ry of the .~ eluant water to the said valve means; :~
:~. 10 ion exchange resin bed means receiving eluant water and selected sample solution from the valve means;
a conductlvity cell receiving the effluent from ,';J the ion exchange resin bed means;
clean up resin bed means receiving the ef1uent ~ ;~
, .
from the conductivity cell;
liquid conduit means connecting in series in a closed loop in the following sequence: the reservoir, the : ;~
hydraulic pressure means, the valve means, the ion exchange resin bed means, the conductivity cell, and the clean up resln bed means;
readout means associated with the conductivity cell;
;I means for delivering to the said valve means, ~ :
~:~ at mutually exclusive times, sample solution, and standard ~- 25 solution;
and a com~uter-controller coordinating the -- :
introduotions of sample solutlon and of standard solution :
~with the readout means.
The:single figure of the drawing is a schematic .
. 30 representation of an integrated system for selecting and ;., : :
~:,.,, : :
~` -16,820-F -2-; ;,~.. . .. .. . ..... ... . . . . . . . .
`
~a3~35~
quantitatively analyzing a solution of one or more ionic ; species according to the invention.
`- In the event the system is used for the analysis of a mixture of carboxylic acids or of . i ~ : carboxylate salts substantially free o~E interference by halide salts or other ionic materiaL that is not ;~Ç
readily separated in the present system from the carboxylic acids or their salts, the column 14 lS
charged with the described cation exchange resin in the hydrogen ion form and the column 15 is simply by-passed upon appropriately regulating the valves j'i 30 and 31. -~-j In carrying out analy~is of solutions , .,;
~, containing substantially only a single cation species paired with a plurality of anion species, the column 14 ~; is charged with an anion exchange resin in easily elutable ~;
. i : ~
anion form such as hydroxide ion or acetate ion and column 15 is not needed and is by-passed, or the aolumn is omitted from the system.
~, 20 In carrying out analysis of solutions containing , :r~
; substantially only a single anion species paired with a ~ ~
,; :
; plurality of cation species, the column 14 is charged with , .,: .
a cation exchange resin in easily elutable cation form such ; ~ !
i~; as sodium ion or lithium ion form. -~`
The ion exchange resins used for chromatographic separations herein exhaust quite slowly, while those which ~ -~
are used for exchange of lon species gradually become i~ exhausted according to their specific exchange capacities, amounts of resin used, and number of equivalents of ion 3Q species in the samples exchanging with the ions at the . . . , : .~ . . ..
:, .
~. ~
16,820-F -3--: ,i active sites of the resins. Preferably, for the sake of economy of operator attention the number of equivalents in selected sizes of samples and the total exchange capacity of the ion exchange resins used permit the ~i 5 analysis of about 17000 to 10,000 or more samples before the charge of resin in a given column becomes exhausted.
As the ion exchange resins approach exhaustion, and generally, at a time determined by experience, the columns are simply removed and replaced by columns charged with resin in the appropriate form.
The ion exchange resins usable in the present method and apparatus are typically polystyrene or modified polystyrene copolymers cross-linked, e.g., with divinyl-benzene, and carrying nuclear groups, the latter providing active exchange sites. The cation exchange resins carry ;
~ nuclear sulfonic acid or sulfonate groups along the polymer -;~j chain. The strong base anlon exchange resins carry nuclear ,? chloromethyl groups which have been quaternized.
The dimensions of the column 17 used to house the clean up resin bed are not critical as analytical separations are not carried out therein. Most any geometry suffices so long as the ion exchange xesin placed therein has a total exchange capacity sufficient to deionize the eluant water effluent from the conductivity ;
cell for a very large number of samples, preferably handling at least as many samples as the ion exchange resins in columns 14 and 15. Usually a column with the same bed volume as that of columns 14 or 15 suffices.
... .
`}
::
i;
:i~
:..
~16,820-F -4-.~;; .
; :. :. :: , . , ~ . . : . . . ~
~` j~
~. ~038~10 ,~ ~
~ Xn general, the column 17 will be charged with - either a two layer bed or a mixed bed resin for deionization ~
of the eluant water. In carrying out total ionic content ~-analyses, both anions and cations in the effluent from the conductivity cell will need to be exchanged for hydroxide ;ions and hydrogen ions respectively in the clean up bed resin. In other analyses where the effluent is only acidic or basic in character, it may be adequate to utilize, `~
in the clean up resin bed column, a single ion exchange resin ;
in the hydroxide ion, or hydrogen ion form, as required, to ; ne~tralize the effluent and effectively transform it into .. . .
substantially deionized water. The quality of the deionized water should be such as to give a very low base line reading, .~ .. ..
~ e.g. r about 2 micromho/cm, when passed through the conducti~
',t,~ 15 vity cell.
The conductivity cell employed is most any o~ the conventional commercially available models regularly used in conductimetric detection chromatography. Most any meter selected is preferably modified, for the present purposes, ' '~'"!~
~ 20 to reduce zero suppression.
s The standard solution used for all but total ionic j content analysis, is a simple aqueous solution containing, : ::~, . .
$ for any given analysis, a mixture of each of the ion species 't ~,;; "' ' ' ~, ~, to be determined, in known concentration, and substantially ~ ;
,3;25 free of ion species which will interfere with analysis by the present method using the present apparatus. The standard ~` used for total ionic content determination may be the pre- ~
selected ion pair issuing from column 13 but also may be ~ 3-;
:5 ' any soluble salt solution of known total ionic content.
~:x, .~ ., ".~
. .
, -, ;.
.," " "
~ 16,820-F -5-- . ~ .
, :v ~0~ 0 ~ ~ ~
The teletypewriter 26 may be any of the commer~
cially available models with a capability of receiving a ~ :
si~gnal from the computer-controller 25 and producing a ~
;i .
print-out or other readout thereof at a remote location. : ':
`i' ;` ~ ~' f~
~,f,~
~" "'; ' .~ :, ,, ' ~`;.',, ~:
:, ,, ~ , ': , ' .1 ` , `3.
., ,,~
~ 1, ~'fl ~ ~
.,' ' ., 1 ' ~':i : .
". !,~ . ~
;.'~ ~" ' ' "."
' ~"~
,'."f'"' ~ , ''~ '~'"'~ : , . . A
'f-' .
~ ~' 1 ' ., ;.` ~1';
f'' .:, . ~ ' ' . '.', ' ' ~'.~'.` ` '.
~',",, , .~ 16,820-F -6- ~ :
The invention relates to an integrated system for the automated quantitative analysis of one or more ionic species utilizing one or more ion exchange resin beds for separations or exchanges, with or without removal of înter- `~
fering ions, and detecting eluted ion species with a con~
ductivity cell. The invention more particularly relates to an integrated system for quantitative analysis of one or more . ;~
ionic species using water for elution of the sample from an ion exchange bed and recycling the water, after purification, ~ -for re-use.
There is a constant and ever increasing demand for a rapid, inexpensive method of analysis of large numbers of samples of, for example, surface waters, i.e., natural waters, boiler blow-down, and manufacturing p}ant efluents for total dissolved solids or a measure thereof, There is also a great need for simple automatable apparatus for carry-ing out such analysis as well as for analysis of process ~ streams for a specified single ion occurring alone except for i a plurality of countervalent ions, or, for analysis of a mixture of organic ca~boxylic acids or the carboxylate salts whether or not in admixture with soluble metal halides.
The determinations in each such case have generally , been carried out using old classical, slow, and relatively costly, methods. Even where ion exchange separations, chroma- - ~
' 25 tographically or by exchange, have been utilized, the fractions ~ ~ -:-, .
` obtained have generally been analyzed by classical methods or by methods which usually require a different test and/or a different instrument for each species to be determined.
Therefore, a new approach with new apparatus appears to be needed.
.
,, ~
~i16,820-F -1-... ,, . , . , .. , , , . , . , . . .. . .. . ~
The invention resides in an integrated system utilizing ion exchange resin means in automated analysis of a sample solution containing at least one ionic species to be quantitatively determined, which comprises~
a reservoir for eluant water; ~ ~:
-^ valve means for selecting a predetermined-sized :~
quantity of sample solution; ~ :
. hydraulic pressure means for deliv~ry of the .~ eluant water to the said valve means; :~
:~. 10 ion exchange resin bed means receiving eluant water and selected sample solution from the valve means;
a conductlvity cell receiving the effluent from ,';J the ion exchange resin bed means;
clean up resin bed means receiving the ef1uent ~ ;~
, .
from the conductivity cell;
liquid conduit means connecting in series in a closed loop in the following sequence: the reservoir, the : ;~
hydraulic pressure means, the valve means, the ion exchange resin bed means, the conductivity cell, and the clean up resln bed means;
readout means associated with the conductivity cell;
;I means for delivering to the said valve means, ~ :
~:~ at mutually exclusive times, sample solution, and standard ~- 25 solution;
and a com~uter-controller coordinating the -- :
introduotions of sample solutlon and of standard solution :
~with the readout means.
The:single figure of the drawing is a schematic .
. 30 representation of an integrated system for selecting and ;., : :
~:,.,, : :
~` -16,820-F -2-; ;,~.. . .. .. . ..... ... . . . . . . . .
`
~a3~35~
quantitatively analyzing a solution of one or more ionic ; species according to the invention.
`- In the event the system is used for the analysis of a mixture of carboxylic acids or of . i ~ : carboxylate salts substantially free o~E interference by halide salts or other ionic materiaL that is not ;~Ç
readily separated in the present system from the carboxylic acids or their salts, the column 14 lS
charged with the described cation exchange resin in the hydrogen ion form and the column 15 is simply by-passed upon appropriately regulating the valves j'i 30 and 31. -~-j In carrying out analy~is of solutions , .,;
~, containing substantially only a single cation species paired with a plurality of anion species, the column 14 ~; is charged with an anion exchange resin in easily elutable ~;
. i : ~
anion form such as hydroxide ion or acetate ion and column 15 is not needed and is by-passed, or the aolumn is omitted from the system.
~, 20 In carrying out analysis of solutions containing , :r~
; substantially only a single anion species paired with a ~ ~
,; :
; plurality of cation species, the column 14 is charged with , .,: .
a cation exchange resin in easily elutable cation form such ; ~ !
i~; as sodium ion or lithium ion form. -~`
The ion exchange resins used for chromatographic separations herein exhaust quite slowly, while those which ~ -~
are used for exchange of lon species gradually become i~ exhausted according to their specific exchange capacities, amounts of resin used, and number of equivalents of ion 3Q species in the samples exchanging with the ions at the . . . , : .~ . . ..
:, .
~. ~
16,820-F -3--: ,i active sites of the resins. Preferably, for the sake of economy of operator attention the number of equivalents in selected sizes of samples and the total exchange capacity of the ion exchange resins used permit the ~i 5 analysis of about 17000 to 10,000 or more samples before the charge of resin in a given column becomes exhausted.
As the ion exchange resins approach exhaustion, and generally, at a time determined by experience, the columns are simply removed and replaced by columns charged with resin in the appropriate form.
The ion exchange resins usable in the present method and apparatus are typically polystyrene or modified polystyrene copolymers cross-linked, e.g., with divinyl-benzene, and carrying nuclear groups, the latter providing active exchange sites. The cation exchange resins carry ;
~ nuclear sulfonic acid or sulfonate groups along the polymer -;~j chain. The strong base anlon exchange resins carry nuclear ,? chloromethyl groups which have been quaternized.
The dimensions of the column 17 used to house the clean up resin bed are not critical as analytical separations are not carried out therein. Most any geometry suffices so long as the ion exchange xesin placed therein has a total exchange capacity sufficient to deionize the eluant water effluent from the conductivity ;
cell for a very large number of samples, preferably handling at least as many samples as the ion exchange resins in columns 14 and 15. Usually a column with the same bed volume as that of columns 14 or 15 suffices.
... .
`}
::
i;
:i~
:..
~16,820-F -4-.~;; .
; :. :. :: , . , ~ . . : . . . ~
~` j~
~. ~038~10 ,~ ~
~ Xn general, the column 17 will be charged with - either a two layer bed or a mixed bed resin for deionization ~
of the eluant water. In carrying out total ionic content ~-analyses, both anions and cations in the effluent from the conductivity cell will need to be exchanged for hydroxide ;ions and hydrogen ions respectively in the clean up bed resin. In other analyses where the effluent is only acidic or basic in character, it may be adequate to utilize, `~
in the clean up resin bed column, a single ion exchange resin ;
in the hydroxide ion, or hydrogen ion form, as required, to ; ne~tralize the effluent and effectively transform it into .. . .
substantially deionized water. The quality of the deionized water should be such as to give a very low base line reading, .~ .. ..
~ e.g. r about 2 micromho/cm, when passed through the conducti~
',t,~ 15 vity cell.
The conductivity cell employed is most any o~ the conventional commercially available models regularly used in conductimetric detection chromatography. Most any meter selected is preferably modified, for the present purposes, ' '~'"!~
~ 20 to reduce zero suppression.
s The standard solution used for all but total ionic j content analysis, is a simple aqueous solution containing, : ::~, . .
$ for any given analysis, a mixture of each of the ion species 't ~,;; "' ' ' ~, ~, to be determined, in known concentration, and substantially ~ ;
,3;25 free of ion species which will interfere with analysis by the present method using the present apparatus. The standard ~` used for total ionic content determination may be the pre- ~
selected ion pair issuing from column 13 but also may be ~ 3-;
:5 ' any soluble salt solution of known total ionic content.
~:x, .~ ., ".~
. .
, -, ;.
.," " "
~ 16,820-F -5-- . ~ .
, :v ~0~ 0 ~ ~ ~
The teletypewriter 26 may be any of the commer~
cially available models with a capability of receiving a ~ :
si~gnal from the computer-controller 25 and producing a ~
;i .
print-out or other readout thereof at a remote location. : ':
`i' ;` ~ ~' f~
~,f,~
~" "'; ' .~ :, ,, ' ~`;.',, ~:
:, ,, ~ , ': , ' .1 ` , `3.
., ,,~
~ 1, ~'fl ~ ~
.,' ' ., 1 ' ~':i : .
". !,~ . ~
;.'~ ~" ' ' "."
' ~"~
,'."f'"' ~ , ''~ '~'"'~ : , . . A
'f-' .
~ ~' 1 ' ., ;.` ~1';
f'' .:, . ~ ' ' . '.', ' ' ~'.~'.` ` '.
~',",, , .~ 16,820-F -6- ~ :
Claims (16)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. Integrated system utilizing ion exchange resin means in automated analysis of a sample solution containing at least one ionic species to be quantitatively determined, which comprises:
a reservoir for eluant water;
valve means for selecting a predetermined-sized quantity of sample solution;
hydraulic pressure means for delivery of the eluant water to the said valve means;
ion exchange resin bed means receiving eluant water and selected sample solution from the valve means;
a conductivity cell receiving the effluent from the ion exchange resin bed means;
clean up resin bed means receiving the effluent from the conductivity cell;
liquid conduit means connecting in series in a closed loop in the following sequence: the reservoir, the hydraulic pressure means, the valve means, the ion exchange resin bed means, the conductivity cell, and the clean up resin bed means;
readout means associated with the conductivity cell;
means for delivering to the said valve means, at mutually exclusive times, sample solution, and standard solution;
and a computer-controller coordinating the introductions of sample solution and of standard solution with the readout means.
a reservoir for eluant water;
valve means for selecting a predetermined-sized quantity of sample solution;
hydraulic pressure means for delivery of the eluant water to the said valve means;
ion exchange resin bed means receiving eluant water and selected sample solution from the valve means;
a conductivity cell receiving the effluent from the ion exchange resin bed means;
clean up resin bed means receiving the effluent from the conductivity cell;
liquid conduit means connecting in series in a closed loop in the following sequence: the reservoir, the hydraulic pressure means, the valve means, the ion exchange resin bed means, the conductivity cell, and the clean up resin bed means;
readout means associated with the conductivity cell;
means for delivering to the said valve means, at mutually exclusive times, sample solution, and standard solution;
and a computer-controller coordinating the introductions of sample solution and of standard solution with the readout means.
2. The system as in Claim 1, wherein each resin bed means is a single tubular column.
3. The system as in Claim 1, wherein the ion exchange resin bed means consists of a first and a second ion exchange resin bed means connected in series, and said bed means are each a single tubular column.
4. The system as in Claim 3, wherein the first column is charged with a cation exchange resin in easily elutable cation form and the second column is charged with an anion exchange resin in easily elutable anion form, said easily elutable cation form being selected from the group consisting of lithium and sodium ion forms and said easily elutable anion form being selected from the group consisting of acetate and hydroxide ion forms.
5. The system as in Claim 3, wherein the first column is charged with a cation exchange resin in the silver ion form and the second column is charged with a cation exchange resin in the hydrogen ion form.
6. The system as in Claim 3, wherein the cation exchange resin in the first column is a homogeneously sul-fonated copolymer of styrene and divinylbenzene.
7. The system as in Claim 3, wherein the cation exchange resin is a low exchange capacity resin.
8. The system as in Claim 1, wherein the ion exchange resin bed means is a single tubular column.
9. The system as in Claim 8, wherein the column is charged with a cation exchange resin in easily elutable cation form.
10. The system as in Claim 8, wherein the column is charged with an anion exchange resin in easily elutable anion form.
11. The system as in Claim 1, wherein the readout means associated with the conductivity cell includes means for transmitting the readout to a remote location.
12. The system as in Claim 1, wherein the means for delivering sample solution to the valve means includes means for selecting the sample solution from natural waters or a manufacturing plant effluent aqueous waste discharge.
13. The system as in Claim 1, wherein the means for delivering sample solution and standard solution to the valve means also includes means for passing bacteri-cidal solution through such delivery means at times mutually exclusive to the delivery of the sample solution and of the standard solution.
14. The system as in Claim 1, wherein the hydraulic pressure means is a pump.
15. The system as in Claim 1, wherein the clean up resin bed means is a single tubular column.
16. The system as in Claim 15, wherein the single tubular column is charged with an ion exchange resin selected from the group consisting of: cation exchange resin in the hydrogen ion form, anion exchange resin in the hydroxide ion form, and, a combination of cation exchange resin in the hydrogen ion form and anion exchange resin in the hydroxide form.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA229,416A CA1038510A (en) | 1975-06-16 | 1975-06-16 | Automated quantitative analysis of ionic species |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA229,416A CA1038510A (en) | 1975-06-16 | 1975-06-16 | Automated quantitative analysis of ionic species |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1038510A true CA1038510A (en) | 1978-09-12 |
Family
ID=4103352
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA229,416A Expired CA1038510A (en) | 1975-06-16 | 1975-06-16 | Automated quantitative analysis of ionic species |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1038510A (en) |
-
1975
- 1975-06-16 CA CA229,416A patent/CA1038510A/en not_active Expired
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