CA1197663A - Potassium sulfate from magnesium sulfate - Google Patents
Potassium sulfate from magnesium sulfateInfo
- Publication number
- CA1197663A CA1197663A CA000424068A CA424068A CA1197663A CA 1197663 A CA1197663 A CA 1197663A CA 000424068 A CA000424068 A CA 000424068A CA 424068 A CA424068 A CA 424068A CA 1197663 A CA1197663 A CA 1197663A
- Authority
- CA
- Canada
- Prior art keywords
- ammonia
- solution
- sulfate
- ammonium sulfate
- potassium
- 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
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
- C01D5/06—Preparation of sulfates by double decomposition
- C01D5/08—Preparation of sulfates by double decomposition with each other or with ammonium sulfate
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Abstract
A B S T R A C T
There is provided an improved process for the preparation of potassium sulfate by the reaction of ammonium sulfate and potassium chloride wherein the improvement comprises reacting an ammonia enriched solution of ammonium sulfate with potassium chloride, the volume of the ammonia-enriched ammonium sulfate solution being such as to afford an economic recovery of ammonia for recycling purposes and a substantially quantitative precipitation of the potassium sulfate.
There is provided an improved process for the preparation of potassium sulfate by the reaction of ammonium sulfate and potassium chloride wherein the improvement comprises reacting an ammonia enriched solution of ammonium sulfate with potassium chloride, the volume of the ammonia-enriched ammonium sulfate solution being such as to afford an economic recovery of ammonia for recycling purposes and a substantially quantitative precipitation of the potassium sulfate.
Description
~197663 The present invention relates to the pro-duction of potassium sulfate from magnesium sulfate.
More specifically, it deals with an improved economlcal process for producing K2S04 from the intermediate (NH4)2S04 generated in the course of recovering useful magnesium salts from magnesium sulfate.
PRIOR ART
The method of recovery of magnesium compounds from magnesium sulfate is well known (for example US
Patent 3 338 667) and calls for the action of ammonia and ammonium carbonate on the starting magnesium sulfate to give hydromagnesia and ammonium sulfate according to the following equation:
g o4 3(NH4)2C03 + 2N~140H + 3H20 3MgC03 Mg(OH)2 3H20 + 4(NH4)2 4 The hydromagnesia is quite insoluble and is separated from the solution by filtration. The solution of (NH4)2S04, containing the excess (NH4)2C03 and NH40H
required for the complete precipitation of hydromagnesia is then the starting material for the production of K2S04 .
It is obvious that the production of K2S04 from (NH4)2S04 can be achieved by a displacement reaction starting from the abundant and relatively cheap KCl, in accordance with the following reaction:
(NH4)2S04 + 2KCl ` K2S04 + 2NH4Cl ~97~3 This basic reaction has been reported previ-ously with similar starting materials such as calcium sulfate (US Patent 3 445 185), mixtures of magnesium sulfate and potassium sulfate (US Patent 3 436 175, US
Patent 3 843 772~, or even magnesium-ammonium phosphate (US Patent 1 820 160).
In these processes, the displacement of the equilibrium in favor of the precipitation of K2SO4 is achieved in two ways.
In a first approach, the addition of methanol or other organic solvents or organic substitutes induce the precipitation of the desired K2SO4 GUS Patents 3 445 185, 3 843 772, 3 436 175, 2 906 603). Such pro-cesses are not of commercial interest because of the high cost of these organic materials or solvents and the problems associated with their recovery. This recovery of organic solvents involves distillation of large amounts of water, a very expensive operation and is never really quantitative. Furthermore, such a pro-cedure would necessary be reflected in a very adverse way on the price of the resulting K2SO4.
Another process involves the precipitation of K2SO4 by makiny the solution very rich in ammonia (US
Patents 1 820 160, 2 882 128). It is known (J. Am.
Chem. Soc., 59, 2096 (1937)) that K2SO4 is rather insoluble in concentrated solution of ammonia. This approach is also well suited to the ammonia/ammonium ~7~i63 sulfate solution obtained from the recovery of hydro-magnesia since an excess of ammonia and ammonium carbon-ate is needed in order to assure the quantitative pre-cipitation of hydromagnesia and, therefore, is already present in the ammonium sulfate solution.
However, the procedures as described in these two patents are not operational for the following reasons. On one hand, high concentrations of ammonia are required to insure the completeness of precipi-10 tation. This is shown by the results of Hill and Loucks(J. Am. Chem. Soc., 59, 2096, (1937)~ reported in Table I.
TABLE I
IN AQUEOUS AMMONIA
Weight Weight 96 NH3 % K2S04 0 10.80 13.90 1.286 18.20 0.639 22.35 0.421 24.83 0.220 27.04 0.1~9 On the other hand, the commercial solutions of NH40H are of the order of 30% maximum. In order to raise the concentration of NH3 to 279~ in the NH40H
solution with 30% NH3, it will be necessary to use ex-cessively large volumes of 3096 NH3 solution. That would make the whole operation quite impractical, part1cularly ~9~6~3 at the recovery stage of ammonia since the starting volume of the ammonium sulfate solution would then have been increased by a factor of the order of ten with the addition of the required 30~ NH3 solution.
Of course, gaseous ammonia could be used. But at the recovery stage, this ammonia would be again in solution and only a complex and expensive process, as known to those familiar in the art, could be used in order to recycle the NH3 in the anhydrous form.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is now provided an improved process which avoids the necessity of adding unduly large volumes of fresh ammonia solution to the starting ammonium sulfate solution. Essentially, this process involves the use of the starting ammonium sulfate solution as a dissolving agent for the gaseous ammonia obtained from a subsequent recycling step thereby to produce an ammonium sulfate solution enriched in ammonia and in a suitable volume for subsequent reaction with potassium chloride and pre-cipitation of the desired potassium sulfate thus also producing a volume suitable for the economic recovery of the gaseous ammonia from the filtrate obtained from said reaction.
More specifically, it is the essence of the present invention to provide a process for obtaining a ~L~976~3 high yield of potass.ium sulfate by the reaction of an ammonia enriched solution of ammonium sulfate and potassium chloride, the ammonia enriched solution of ammonium sulfate being of a volume size such that after removal of the precipitated potassium sulfate, the volume of the filtrate comprising ammonium chloride and ammonium hydroxide is such that the recovery of ammonia is commercially feasible.
It has also been found, in accordance with the present invention, that by using an ammonium sulfate solution as an absorbent for the recycled ammonia, huge volumes of water do not have to be used to produce an ammonia enriched solution of ammonium sulfate in oppo-sition to the volume of water which would be required to attain an ammonia enriched solution of ammonium sulfate of the same ammonia concentration if a commercial ammonia solution was used. According to the novel improved process the present invention there is also provided a volume of filtrate which can be economiCally treated to recover ammonia suitable for recycling in the first step of the process of the present invention.
It is also a feature of the present invention that by using an enriched ammonia solution of ammonium sulfate there is first obtained a higher yield of potassium sulfate. Secondly, because of the lower volume of filtrate after removal of the precipitated potassium sulfate there is provided a most economic ~7~6~3 procedure for recovering ammonia for recycling purposes in the present invention.
The recovery operation of the ammonia is also simplified by adding lime to the resulting ammonium chloride solution thus increasing the basicity of the filtrate allowing for the liberation of further amounts of ammonia from the chloride ion and facilitating the operation by decreasing in a very substantial way the volume of water to be distilled to reclaim the ammonia.
The reactions involved in the various steps of the present invention for the formation of potassium sulfate and recovery of ammonia are illustrated as follows:
(NH4)2S04 + 2KCl + NH40H(excess) >
K2S04~ + 2NH~Cl + NH40H(excess) 2NH4C1 + NH40H(excess) + l.lCa(OH)2 >
CaC12 + O.lCa(OH)2 NH40H(excess) The advantages of operating in the presence of an excess of lime are illustrated in Table II where the amount of water to be distilled in order to recover ammonia from its solution is shown. The advantage of operating in the presence of lime is obvious from the examination of these data.
~3~97~6~
TABLE II
Percentage of a 25% NH3 Percentage of evaporated solution distilled (%) ammonia _ In the presence In the absence . of CaO of CaO
_ _ _ 1.9 53 65 9 90 87.5 96.96 ~9 99.64 89.5 99.8 99.92 It can be noted that in the presence of an excess of Ca(OH)2, after the distillation of 20% of the water from the NH3 solution, the recovery of ammonia is essentially complete whereas without Ca(OH)2, only 90%
of the ammonia has been recovered after distillation of 20% of the ammonia solution.
THE AMMONIA ENRICHMENT
The starting stock solution of ammonium sulfate has an ammonia content of from 13 to 17~ by weight. After its enrichment with gaseous ammonia its ammonia concentration is about from 29 to 31% weight without significant increase in volume, with a content of about 30% by weight of ammonia being preferred.
76~3 The enrichment step must be carried out prior to the reaction with potassium chloride to allow for the full enrichment in ammonia of the ammonium sulfate solution. This is done by passing the ammonium sulfate solution in a scrubbing tower with gaseous ammonia circulating in countercurrent of the ammonium sulfate solution. It should be appreciated that the reaction between the ammonium sulfate and the potassium chloride must not take place in the scrubbing tower because the immediate precipitation of potassium sulfate would prevent the circulation of the ammonia and the solution by obturating the trays or the lining of the scrubbing tower.
It will also be appreciated that since the absorption of the ammonia in the ammonium sulfate solution is an exothermic reaction the scrubbing tower must therefore be equipped with cooling units to favour the absorption of the ammonia at low temperatures. It is well obvious to those skilled in the art that pre-cipitation must be avoided in such a system.
DESCRIPTI02~ OF DRAWING
A stock solution 10 of ammonium sulfate con-taining ammonium carbonate obtained from the carbonation of a magnesium sulfate solution 11 or from any other source is cooled to a temperature between about 5 and 10C in a heat exchanger 12 to improve the capacity of the ammonium sulfate to dissolve ammonia. After ~L~9~6~3 g cooling the ammonium sulfate solution is introduced into a scrubbing tower 14 equipped with plates or other standard lining so that ammonia vapors 16 admitted countercurrently are absorbed by the ammonium sulfate solution in the scrubbing tower 14. Since there is a substantial heat accompanying the solution of the ammonia 16 it is useful to have a heat exchanger or equivalent arrangement at the level of each plate in order to keep the ammonia scrubbing solution at a temperature of from 5 to 10C, preferably about 7C.
The ammonium sulfate solution saturated with ammonia 17 is withdrawn and directed to a reactor 18 to which is then added potassium chloride 20 thereby causing immedi-ate precipitation of potassium sulfate. The reaction mixture from the reactor 20 is subjected to filtration 21 or any suitable separation means to separate the slurry of potassium sulfate 22 from the mother liquor 24. The slurry 22 of potassium sulfate from the solid is then washed with water 26 saturated with ammonia and the washing 28 are then recycled to reactor 18 while the solid potassium sulfate 30 is recovered.
The mother liquors 24 are then directed to a two-stage stripper 32 where the temperature is raised to 55C and then to 90C. From the zone 32A of the two-stage stripper 32 heated at 55C there is recovered a portion of ammonia gas 34 which is directed to an ammonia reservoir 36. From the zone 32B of the two-~766~3 stage stripper 32 heated at 90C there is recovered ahot ammonia solution 38 which is distilled in flash boiler 40 to which lime 42 has been added. Calcium chloride 44 is formed while after distillation of about 25~ of the volume of water there is obtained an essen-tially quantitative recovery of gaseous ammonia 46 which after cooling in a heat exchanger 4~ can be returned to the ammonia reservoir 36. The ammonia 16 can be return-ed to the scrubbing tower 14 for the saturation of a new batch of magnesium sulfate stock solution 10. The two-stage stripper 32 will also yield a mixture of ammonia and carbon dioxide 50 which upon cooling below 60C will give ammonium carbonate, which can be directed to the carbonation of the starting magnesium sulfate solution 11 .
The process of the present invention will be more readily understood by referring to Table III which illustrates the various steps described herein and in Figure 1.
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More specifically, it deals with an improved economlcal process for producing K2S04 from the intermediate (NH4)2S04 generated in the course of recovering useful magnesium salts from magnesium sulfate.
PRIOR ART
The method of recovery of magnesium compounds from magnesium sulfate is well known (for example US
Patent 3 338 667) and calls for the action of ammonia and ammonium carbonate on the starting magnesium sulfate to give hydromagnesia and ammonium sulfate according to the following equation:
g o4 3(NH4)2C03 + 2N~140H + 3H20 3MgC03 Mg(OH)2 3H20 + 4(NH4)2 4 The hydromagnesia is quite insoluble and is separated from the solution by filtration. The solution of (NH4)2S04, containing the excess (NH4)2C03 and NH40H
required for the complete precipitation of hydromagnesia is then the starting material for the production of K2S04 .
It is obvious that the production of K2S04 from (NH4)2S04 can be achieved by a displacement reaction starting from the abundant and relatively cheap KCl, in accordance with the following reaction:
(NH4)2S04 + 2KCl ` K2S04 + 2NH4Cl ~97~3 This basic reaction has been reported previ-ously with similar starting materials such as calcium sulfate (US Patent 3 445 185), mixtures of magnesium sulfate and potassium sulfate (US Patent 3 436 175, US
Patent 3 843 772~, or even magnesium-ammonium phosphate (US Patent 1 820 160).
In these processes, the displacement of the equilibrium in favor of the precipitation of K2SO4 is achieved in two ways.
In a first approach, the addition of methanol or other organic solvents or organic substitutes induce the precipitation of the desired K2SO4 GUS Patents 3 445 185, 3 843 772, 3 436 175, 2 906 603). Such pro-cesses are not of commercial interest because of the high cost of these organic materials or solvents and the problems associated with their recovery. This recovery of organic solvents involves distillation of large amounts of water, a very expensive operation and is never really quantitative. Furthermore, such a pro-cedure would necessary be reflected in a very adverse way on the price of the resulting K2SO4.
Another process involves the precipitation of K2SO4 by makiny the solution very rich in ammonia (US
Patents 1 820 160, 2 882 128). It is known (J. Am.
Chem. Soc., 59, 2096 (1937)) that K2SO4 is rather insoluble in concentrated solution of ammonia. This approach is also well suited to the ammonia/ammonium ~7~i63 sulfate solution obtained from the recovery of hydro-magnesia since an excess of ammonia and ammonium carbon-ate is needed in order to assure the quantitative pre-cipitation of hydromagnesia and, therefore, is already present in the ammonium sulfate solution.
However, the procedures as described in these two patents are not operational for the following reasons. On one hand, high concentrations of ammonia are required to insure the completeness of precipi-10 tation. This is shown by the results of Hill and Loucks(J. Am. Chem. Soc., 59, 2096, (1937)~ reported in Table I.
TABLE I
IN AQUEOUS AMMONIA
Weight Weight 96 NH3 % K2S04 0 10.80 13.90 1.286 18.20 0.639 22.35 0.421 24.83 0.220 27.04 0.1~9 On the other hand, the commercial solutions of NH40H are of the order of 30% maximum. In order to raise the concentration of NH3 to 279~ in the NH40H
solution with 30% NH3, it will be necessary to use ex-cessively large volumes of 3096 NH3 solution. That would make the whole operation quite impractical, part1cularly ~9~6~3 at the recovery stage of ammonia since the starting volume of the ammonium sulfate solution would then have been increased by a factor of the order of ten with the addition of the required 30~ NH3 solution.
Of course, gaseous ammonia could be used. But at the recovery stage, this ammonia would be again in solution and only a complex and expensive process, as known to those familiar in the art, could be used in order to recycle the NH3 in the anhydrous form.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is now provided an improved process which avoids the necessity of adding unduly large volumes of fresh ammonia solution to the starting ammonium sulfate solution. Essentially, this process involves the use of the starting ammonium sulfate solution as a dissolving agent for the gaseous ammonia obtained from a subsequent recycling step thereby to produce an ammonium sulfate solution enriched in ammonia and in a suitable volume for subsequent reaction with potassium chloride and pre-cipitation of the desired potassium sulfate thus also producing a volume suitable for the economic recovery of the gaseous ammonia from the filtrate obtained from said reaction.
More specifically, it is the essence of the present invention to provide a process for obtaining a ~L~976~3 high yield of potass.ium sulfate by the reaction of an ammonia enriched solution of ammonium sulfate and potassium chloride, the ammonia enriched solution of ammonium sulfate being of a volume size such that after removal of the precipitated potassium sulfate, the volume of the filtrate comprising ammonium chloride and ammonium hydroxide is such that the recovery of ammonia is commercially feasible.
It has also been found, in accordance with the present invention, that by using an ammonium sulfate solution as an absorbent for the recycled ammonia, huge volumes of water do not have to be used to produce an ammonia enriched solution of ammonium sulfate in oppo-sition to the volume of water which would be required to attain an ammonia enriched solution of ammonium sulfate of the same ammonia concentration if a commercial ammonia solution was used. According to the novel improved process the present invention there is also provided a volume of filtrate which can be economiCally treated to recover ammonia suitable for recycling in the first step of the process of the present invention.
It is also a feature of the present invention that by using an enriched ammonia solution of ammonium sulfate there is first obtained a higher yield of potassium sulfate. Secondly, because of the lower volume of filtrate after removal of the precipitated potassium sulfate there is provided a most economic ~7~6~3 procedure for recovering ammonia for recycling purposes in the present invention.
The recovery operation of the ammonia is also simplified by adding lime to the resulting ammonium chloride solution thus increasing the basicity of the filtrate allowing for the liberation of further amounts of ammonia from the chloride ion and facilitating the operation by decreasing in a very substantial way the volume of water to be distilled to reclaim the ammonia.
The reactions involved in the various steps of the present invention for the formation of potassium sulfate and recovery of ammonia are illustrated as follows:
(NH4)2S04 + 2KCl + NH40H(excess) >
K2S04~ + 2NH~Cl + NH40H(excess) 2NH4C1 + NH40H(excess) + l.lCa(OH)2 >
CaC12 + O.lCa(OH)2 NH40H(excess) The advantages of operating in the presence of an excess of lime are illustrated in Table II where the amount of water to be distilled in order to recover ammonia from its solution is shown. The advantage of operating in the presence of lime is obvious from the examination of these data.
~3~97~6~
TABLE II
Percentage of a 25% NH3 Percentage of evaporated solution distilled (%) ammonia _ In the presence In the absence . of CaO of CaO
_ _ _ 1.9 53 65 9 90 87.5 96.96 ~9 99.64 89.5 99.8 99.92 It can be noted that in the presence of an excess of Ca(OH)2, after the distillation of 20% of the water from the NH3 solution, the recovery of ammonia is essentially complete whereas without Ca(OH)2, only 90%
of the ammonia has been recovered after distillation of 20% of the ammonia solution.
THE AMMONIA ENRICHMENT
The starting stock solution of ammonium sulfate has an ammonia content of from 13 to 17~ by weight. After its enrichment with gaseous ammonia its ammonia concentration is about from 29 to 31% weight without significant increase in volume, with a content of about 30% by weight of ammonia being preferred.
76~3 The enrichment step must be carried out prior to the reaction with potassium chloride to allow for the full enrichment in ammonia of the ammonium sulfate solution. This is done by passing the ammonium sulfate solution in a scrubbing tower with gaseous ammonia circulating in countercurrent of the ammonium sulfate solution. It should be appreciated that the reaction between the ammonium sulfate and the potassium chloride must not take place in the scrubbing tower because the immediate precipitation of potassium sulfate would prevent the circulation of the ammonia and the solution by obturating the trays or the lining of the scrubbing tower.
It will also be appreciated that since the absorption of the ammonia in the ammonium sulfate solution is an exothermic reaction the scrubbing tower must therefore be equipped with cooling units to favour the absorption of the ammonia at low temperatures. It is well obvious to those skilled in the art that pre-cipitation must be avoided in such a system.
DESCRIPTI02~ OF DRAWING
A stock solution 10 of ammonium sulfate con-taining ammonium carbonate obtained from the carbonation of a magnesium sulfate solution 11 or from any other source is cooled to a temperature between about 5 and 10C in a heat exchanger 12 to improve the capacity of the ammonium sulfate to dissolve ammonia. After ~L~9~6~3 g cooling the ammonium sulfate solution is introduced into a scrubbing tower 14 equipped with plates or other standard lining so that ammonia vapors 16 admitted countercurrently are absorbed by the ammonium sulfate solution in the scrubbing tower 14. Since there is a substantial heat accompanying the solution of the ammonia 16 it is useful to have a heat exchanger or equivalent arrangement at the level of each plate in order to keep the ammonia scrubbing solution at a temperature of from 5 to 10C, preferably about 7C.
The ammonium sulfate solution saturated with ammonia 17 is withdrawn and directed to a reactor 18 to which is then added potassium chloride 20 thereby causing immedi-ate precipitation of potassium sulfate. The reaction mixture from the reactor 20 is subjected to filtration 21 or any suitable separation means to separate the slurry of potassium sulfate 22 from the mother liquor 24. The slurry 22 of potassium sulfate from the solid is then washed with water 26 saturated with ammonia and the washing 28 are then recycled to reactor 18 while the solid potassium sulfate 30 is recovered.
The mother liquors 24 are then directed to a two-stage stripper 32 where the temperature is raised to 55C and then to 90C. From the zone 32A of the two-stage stripper 32 heated at 55C there is recovered a portion of ammonia gas 34 which is directed to an ammonia reservoir 36. From the zone 32B of the two-~766~3 stage stripper 32 heated at 90C there is recovered ahot ammonia solution 38 which is distilled in flash boiler 40 to which lime 42 has been added. Calcium chloride 44 is formed while after distillation of about 25~ of the volume of water there is obtained an essen-tially quantitative recovery of gaseous ammonia 46 which after cooling in a heat exchanger 4~ can be returned to the ammonia reservoir 36. The ammonia 16 can be return-ed to the scrubbing tower 14 for the saturation of a new batch of magnesium sulfate stock solution 10. The two-stage stripper 32 will also yield a mixture of ammonia and carbon dioxide 50 which upon cooling below 60C will give ammonium carbonate, which can be directed to the carbonation of the starting magnesium sulfate solution 11 .
The process of the present invention will be more readily understood by referring to Table III which illustrates the various steps described herein and in Figure 1.
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Claims (5)
1. In a process for the preparation of po-tassium sulfate by the reaction of ammonium sulfate and potassium chloride, the improvement wherein the solution of ammonium sulfate is enriched in ammonia by saturating said solution with ammonia obtained from a subsequent recovery step of the filtrate obtained after precipi-tating potassium sulfate by the reaction of potassium chloride with said ammonia-enriched ammonium sulfate solution.
2. The process of Claim 1, wherein the ammonia content of the ammonia-enriched ammonium sulfate solution is from 29 to 31% in volume.
3. The method of Claim 1, wherein the ammonia content of the ammonia-enriched ammonium sulfate solution is 30% by volume.
4. The method of Claims 1, 2 or 3, wherein the saturating step is carried out at a temperature of from 5-10°C.
5. The method of Claims 1, 2 or 3, wherein the saturating step is carried out at a temperature of about 7°C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000424068A CA1197663A (en) | 1983-03-21 | 1983-03-21 | Potassium sulfate from magnesium sulfate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000424068A CA1197663A (en) | 1983-03-21 | 1983-03-21 | Potassium sulfate from magnesium sulfate |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1197663A true CA1197663A (en) | 1985-12-10 |
Family
ID=4124835
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000424068A Expired CA1197663A (en) | 1983-03-21 | 1983-03-21 | Potassium sulfate from magnesium sulfate |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1197663A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999065823A1 (en) * | 1998-06-16 | 1999-12-23 | Airborne Industrial Minerals Inc. | Method of procucing potassium sulfate |
| CN104386713A (en) * | 2014-10-30 | 2015-03-04 | 河北工业大学 | Method for preparing potassium sulfate from potassium chloride and ammonium sulfate |
| CN106335910A (en) * | 2016-08-25 | 2017-01-18 | 辽宁津大肥业有限公司 | Potassium sulfate and ammonium chloride preparation method |
| CN112591768A (en) * | 2020-09-01 | 2021-04-02 | 安徽海默科技股份有限公司 | Process for producing potassium sulfate and ammonium potassium chloride by using phosphogypsum |
-
1983
- 1983-03-21 CA CA000424068A patent/CA1197663A/en not_active Expired
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999065823A1 (en) * | 1998-06-16 | 1999-12-23 | Airborne Industrial Minerals Inc. | Method of procucing potassium sulfate |
| US6315976B1 (en) | 1998-06-16 | 2001-11-13 | Aristos Capital Corporation | Method of producing potassium sulfate |
| CN104386713A (en) * | 2014-10-30 | 2015-03-04 | 河北工业大学 | Method for preparing potassium sulfate from potassium chloride and ammonium sulfate |
| CN104386713B (en) * | 2014-10-30 | 2016-04-06 | 河北工业大学 | A kind of method of Repone K and ammonium sulfate preparing potassium sulfate |
| CN106335910A (en) * | 2016-08-25 | 2017-01-18 | 辽宁津大肥业有限公司 | Potassium sulfate and ammonium chloride preparation method |
| CN112591768A (en) * | 2020-09-01 | 2021-04-02 | 安徽海默科技股份有限公司 | Process for producing potassium sulfate and ammonium potassium chloride by using phosphogypsum |
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