GB1584704A - Process for the preparation of sodium bisulphate granules - Google Patents
Process for the preparation of sodium bisulphate granules Download PDFInfo
- Publication number
- GB1584704A GB1584704A GB43993/79A GB4399379A GB1584704A GB 1584704 A GB1584704 A GB 1584704A GB 43993/79 A GB43993/79 A GB 43993/79A GB 4399379 A GB4399379 A GB 4399379A GB 1584704 A GB1584704 A GB 1584704A
- Authority
- GB
- United Kingdom
- Prior art keywords
- sodium bisulphate
- granulation
- sulphate
- temperature
- sodium
- 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
- WBHQBSYUUJJSRZ-UHFFFAOYSA-M sodium bisulfate Chemical compound [Na+].OS([O-])(=O)=O WBHQBSYUUJJSRZ-UHFFFAOYSA-M 0.000 title claims description 39
- 238000000034 method Methods 0.000 title claims description 31
- 239000008187 granular material Substances 0.000 title claims description 20
- 238000002360 preparation method Methods 0.000 title claims description 8
- 238000005469 granulation Methods 0.000 claims description 20
- 230000003179 granulation Effects 0.000 claims description 18
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 claims description 14
- 239000000155 melt Substances 0.000 claims description 12
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 claims description 11
- 235000002639 sodium chloride Nutrition 0.000 claims description 10
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 claims description 8
- 150000001875 compounds Chemical class 0.000 claims description 8
- 239000001175 calcium sulphate Substances 0.000 claims description 7
- 235000011132 calcium sulphate Nutrition 0.000 claims description 7
- 238000011282 treatment Methods 0.000 claims description 7
- TZCXTZWJZNENPQ-UHFFFAOYSA-L barium sulfate Chemical compound [Ba+2].[O-]S([O-])(=O)=O TZCXTZWJZNENPQ-UHFFFAOYSA-L 0.000 claims description 6
- 229910052943 magnesium sulfate Inorganic materials 0.000 claims description 6
- 235000019341 magnesium sulphate Nutrition 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims description 5
- 239000011780 sodium chloride Substances 0.000 claims description 5
- 229910052938 sodium sulfate Inorganic materials 0.000 claims description 4
- 235000011152 sodium sulphate Nutrition 0.000 claims description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims description 3
- 239000001117 sulphuric acid Substances 0.000 claims description 3
- 235000011149 sulphuric acid Nutrition 0.000 claims description 3
- 239000007921 spray Substances 0.000 claims description 2
- 239000003795 chemical substances by application Substances 0.000 claims 1
- 238000001816 cooling Methods 0.000 description 14
- 238000005507 spraying Methods 0.000 description 9
- 230000009466 transformation Effects 0.000 description 8
- 150000003839 salts Chemical class 0.000 description 4
- 238000005054 agglomeration Methods 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-M bisulphate group Chemical group S([O-])(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-M 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000007654 immersion Methods 0.000 description 2
- 230000001131 transforming effect Effects 0.000 description 2
- 241000272470 Circus Species 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 230000007775 late Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- -1 salt hydrates Chemical class 0.000 description 1
- 238000007873 sieving Methods 0.000 description 1
- 150000004760 silicates Chemical class 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
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
- C01D5/02—Preparation of sulfates from alkali metal salts and sulfuric acid or bisulfates; Preparation of bisulfates
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
- Y02P20/129—Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
- Fertilizers (AREA)
- Glanulating (AREA)
Description
PATENT SPECIFICATION
( 11) ( 21) Application No 43993/79 ( 22) Filed 4 May 1977 b ( 62) Divided out of No 1 584 702 ( 31) Convention Application No.
2619811 ( 32) Filed 5 May 1976 in mg) ( 33) Fed Rep of Germany (DE) ( 44) Complete Specification published 18 Feb 1981 ( 51) INT CL 3 CO 1 D 5/02 ( 52) Index at acceptance C 1 A D 19 G 50 G 50 D 19 PF 5 ( 54) PROCESS FOR THE PREPARATION OF SODIUM BISULPHATE GRANULES ( 71) We, HOECHST AKTIENGESELLSCHAFT, a body corporate organised according to the laws of the Federal Republic of Germany, of 6230 Frankfurt/ Main 80, Postfach 80 03 20, Federal Republic of Germany, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:-
The present invention relates to the preparation of sodium bisulphate granules.
Granulation of sodium bisulphate may for example be carried out by transforming into scales or by spraying in a cooling tower or on to a cooling strip It has been ascertained, however, that the granulated sodium bisulphate produced from a melt is mainly present in a vitreous, metastable state, and therefore it can be processed only with difficulty When this granulated product is stored in silos, barrels or sacks, its metastable phase is transformed into the stable phase over approximately 24 hours, and a considerable quantity of heat is evolved whereby the temperature may increase by up to 100 C At the same time the product hardens to such a degree that it can be transformed into a form ready for use only with considerable expenditure, by crushing and sieving it Freshly granulated product in the metastable state can also only be crushed with difficulty, as it behaves like a tough mass There is therefore a need to transform the granules largely or entirely into a stable form prior to storage or further processing.
The invention provides a process for the preparation of sodium bisulphate granules which comprises granulating molten sodium bisulphate in the presence of finely divided calcium sulphate, magnesium sulphate, barium sulphate, sodium sulphate or sodium bisulphate or a mixture of two or more such compounds in an amount of from 0 1 to 5 % by weight, the compound or compounds being present before granulation The transformation of the metastable granulated sodium bisulphate is accelerated by these additives, and again non-sticking granules are produced The compound or compounds may be added to the melt after it has been prepared and before granulation However, instead of adding pure magnesium or calcium sulphate, crude non-purified rock salt, 55 which contains these sulphates, may be used as a starting material in the preparation of the bisulphate A portion of at least 20 % by weight of non-purified rock salt is advantageous The addition of finely pulverized 60 sodium bisulphate or sodium sulphate is only advisable when it is effected shortly before the granulation Silicates have proved inefficient.
The melt may be granulated in any suit 65 able manner, for example by spraying in a spray tower (whereby the liquid bisulphate solidifies during the free fall), by solidification on a cooling strip or on a scale roll.
By the process of the present invention 70 the transformation of the metastable form of granulated sodium bisulphate into the stable form is accelerated.
A product which has not been stabilized may be subject to a sudden temperature 75 increase accompanied by agglomeration, even after several days, whereas the stabilized granulate is storable without difficulty over a long period of time.
The acceleration of the transformation of 80 the metastable form of granulated sodium bisulphate into the stable form may also be improved, after granulation, by keeping the granulated product for at least one minute at a temperature in the range of from 60 to 85 C The resulting product consists of non-sticking granules This individual process is described and claimed in our copending application no 7 938 193 (Serial No.
1 584 703), and may be carried out in addi 90 tion to the process of the present invention.
The transformation into the stable phase in the given temperature range takes place faster the higher the temperature At a temperature of from 50 to 60 C the transforma 95 tion requires about 24 hours, at a temperature of 100 C about 10 minutes and at a temperature of from 120 to 140 C about 1 minute The transformation could therefore be carried out at a temperature in the range 100 1 584 704 1 584 704 of from 50 to 60 WC, but long residence times are not very economical A temperature in the range of from 120 to 140 WC is preferred.
The above past-granulation temperature treatment may be carried out for example as follows:
A sodium bisulphate melt at 260 WC is sprayed in a cooling tower through nozzles and the temperature of the solidified granules is adjusted to about 650 C by using a suitable quantity of cooling air during spraying and by preheating the air The product is stored at this temperature for about minutes The solidified granules remain free flowing even after several weeks and can readily be further processed.
Alternatively, the operation may be carried out as above except that the solidified granules are cooled only to a temperature of about 100 C during granulation The temperature of 1000 C is maintained for 10 minutes This residence time is sufficient for the complete transformation of the metastable sodium bisulphate Even after a rather long period of time the product does not agglomerate.
The above treatments can easily be combined with the process of the invention.
The transformation of the metastable sodium bisulphate into the stable form can also be accelerated by increasing the water content of the melt to 0 01 to 3 % by weight of water, prior to granulation, and this can be carried out in addition to the abovedescribed process of the invention Nonsticking granules are produced.
This variant of the process according to the invention is applicable, for example, to granulation on a scale roll, and, preferably, to spraying in a cooling tower, whereby the molten sodium bisulphate solidifies during the free fall It is thought that, in the presence of water, primary salt hydrates are formed which act as catalyst for the transformation of the metastable phase into the stable phase.
This treatment may be carried out for example as follows:
4000 kg per hour of sodium bisul phate melt (content of sodium bisulphate 965 %) are produced in a circulation reactor The melt is sprayed in the cooling tower (quantity of steam 20 kg per hour) by means of bi-component nozzles.
The product obtained is substantially stable and can be further processed without difficulty (water content:0 15 %).
For transforming the metastableform of sodium bisulphate into the stable form, it has moreover proved advantageous to adjust the temperature of the melt prior to granulating to be within a well defined range, from 186 to 236 WC whereby nonsticking granules are produced The cooling speed in 'C per unit of time is lower in this temperature range than when cooling a melt which has a temperature of from 240 to 280 WC to the same final temperature and, as a consequence thereof, most of the sodium bisulphate solidifies in the desired stable 70 phase This applies especially to granulation in a spraying tower This process may also be carried out in addition to the process of the invention.
This pre-granulation treatment may be 75 carried out for example as follows:
1100 1 of technical grade sulphuric acid (d 1 84) and 1200 kg of marine salt are fed into a circulation reactor per hour to produce a sodium bisulphate melt The temper 80 ature of the melt is maintained at 260 C by burning 210 m 3/hour of hydrogen with air in an immersion heater On its way to the spraying tower the melt is cooled to 220 WC by a cooled tube mounted directly before 85 the spraying nozzles The granules are cooled to 4 C by cooling air in the spraying tower.
These granules have only a moderate tendency to get sticky and can subsequently be 90 further processed without essential difficulties.
The above treatments can easily be combined with the process of the invention.
The above methods for the transforma 95 tion of metastable sodium bisulphate give maximum useful yields from a given reactor.
They are suitable for the granulation of products produced in a submerged combustion burner, a circulation reactor which circu 100 lates the melt, directly heated by means of an immersion heater, and also for products obtained from processes for the preparation of fluid sodium bisulphate The melt may be produced, for example, by the process 105 described and claimed in our copending application no 18660/77 (Serial No.
1 584 702).
It is also possible to use two or more of the optional treatment processes which 110 assist the preparation of non-sticky sodium bisulphate granules, together with the process of the invention The effects of the individual measures are thereby increased.
The following Examples, l to 3 illustrate 115 the invention:
Comparative Example A sodium bisulphate melt at 260 C was sprayed in a cooling tower through nozzles and the solidified granules were cooled to 120 C by means of cold air and then stored in containers Over several hours, the product was subject to a self-heating to about 1250 C, whereby the product agglomerated forming blocks as hard as stone Consequently, the 125 product was not suitable for further use.
EXAMPLE 1:
kg/hour of finely divided calcium sulphate were added to 4000 kg/hour of melt at 260 C having a content of 96 5 % by weight 130 1 584 704 of sodium bisulphate, and prepared from marine salt After spraying in a cooling tower and cooling to 35 C the granulated product was substantially stable and could be stored without self-heating and agglomeration.
EXAMPLE 2:
Example 1 was repeated, except that the same quantity of magnesium sulphate was used instead of calcium sulphate The granulated sodium bisulphate was completely stable.
EXAMPLE 3:
A sodium bisulphate melt at 2550 C prepared from sulphuric acid and salt, 78 % by weight of which was marine salt and 22 % by weight non-purified industrial rock salt, was sprayed in a cooling tower and cooled to 350 C The result was the same as in Example 1.
Claims (1)
- WHAT WE CLAIM IS:1 A process for the preparation of sodium bisulphate granules which comprises granulating molten sodium bisulphate in the presence of from 0 1 to 5 % by weight of finely divided calcium sulphate, magnesium sulphate, barium sulphate, sodium sulphate or sodium bisulphate or a mixture of two or more such compounds, the compound or compounds being present before granulation.2 A process as claimed in claim 1, wherein the calcium sulphate, magnesium sulphate, barium sulphate, sodium sulphate or sodium bisulphate or mixture thereof is added to the sodium bisulphate melt after it has been prepared and before granulation.3 A process as claimed in claim 1, wherein the sodium bisulphate has been prepared by reacting non-purified rock salt with sulphuric acid in a melt of sodium bisulphate, whereby magnesium sulphate and calcium sulphate present in the rock salt are incorporated in the molten sodium bisulphate 45 4 A process as claimed in any one of claims 1 to 3, wherein granulation is carried out in a spray tower.A process as claimed in claim 1, carried out substantially as described in any 50 one of the Examples 1 to 3 herein.6 A process as claimed in any one of claims 1 to 5, wherein after granulation the granules are held for at least one minute at a temperature in the range of from 60 to 55 C.7 A process as claimed in claim 6, wherein the granules are held at a temperature in the range of from 120 to 140 'C.8 A process as claimed in claim 6, 60 wherein the post-granulation treatment is carried out substantially as described herein.9 A process as claimed in any one of claims 1 to 8, wherein granulation of the molten sodium bisulphate is carried out in 65 the presence of from 0 01 to 3 % by weight of water.A process as claimed in claim 9, wherein water is added substantially as described herein 70 11 A process as claimed in any one of claims 1 to 10, wherein the temperature of the molten sodium bisulphate is adjusted to be in the range of from 186 to 2360 C before granulation from this temperature 75 12 A process as claimed in claim 11, wherein the pre-granulation temperature adjustment is carried out substantially as described herein.13 Sodium bisulphate, whenever pre 80 pared by a process as claimed in any one of claims 1 to 12.ABEL & IMRAY Chartered Patent Agents, Northumberland House, 303-306 High Holborn, London, WC 1 V 7 LH.Printed for Her Majesty's Stationery Office by The Tweeddale Press Ltd, Berwick-upon-Tweed, 1980 Published at the Patent Office, 25 Southampton Buildings, London, WC 2 A l AY, from which copies may be obtained.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2619811A DE2619811C2 (en) | 1976-05-05 | 1976-05-05 | Process for the production of sodium bisulfate |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1584704A true GB1584704A (en) | 1981-02-18 |
Family
ID=5977112
Family Applications (3)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB43993/79A Expired GB1584704A (en) | 1976-05-05 | 1977-05-04 | Process for the preparation of sodium bisulphate granules |
| GB18660/77A Expired GB1584702A (en) | 1976-05-05 | 1977-05-04 | Process for the preparation of sodium bisulphate |
| GB38193/79A Expired GB1584703A (en) | 1976-05-05 | 1977-05-04 | Process for the preparation of sodium bisulphate granules |
Family Applications After (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB18660/77A Expired GB1584702A (en) | 1976-05-05 | 1977-05-04 | Process for the preparation of sodium bisulphate |
| GB38193/79A Expired GB1584703A (en) | 1976-05-05 | 1977-05-04 | Process for the preparation of sodium bisulphate granules |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPS52133899A (en) |
| BE (1) | BE854299A (en) |
| DE (1) | DE2619811C2 (en) |
| FR (2) | FR2350302A1 (en) |
| GB (3) | GB1584704A (en) |
| IT (1) | IT1075526B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7067094B2 (en) * | 2003-09-09 | 2006-06-27 | Grillo-Werke Ag | Process for the brightening of sodium hydrogensulfate |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2810693C2 (en) * | 1978-03-11 | 1982-07-15 | Hoechst Ag, 6000 Frankfurt | Process for the continuous production of sodium bisulfate |
| CN102153111B (en) * | 2011-02-28 | 2012-07-04 | 绍兴市东湖生化有限公司 | Method for preparing anhydrous sodium hydrogen sulfate by using ethephon production waste liquid |
| CN116924344B (en) * | 2023-09-15 | 2023-11-17 | 潍坊石大昌盛能源科技有限公司 | Granulating method of sodium hydrosulfide |
-
1976
- 1976-05-05 DE DE2619811A patent/DE2619811C2/en not_active Expired
-
1977
- 1977-05-03 IT IT23136/77A patent/IT1075526B/en active
- 1977-05-04 GB GB43993/79A patent/GB1584704A/en not_active Expired
- 1977-05-04 GB GB18660/77A patent/GB1584702A/en not_active Expired
- 1977-05-04 GB GB38193/79A patent/GB1584703A/en not_active Expired
- 1977-05-04 JP JP5085677A patent/JPS52133899A/en active Pending
- 1977-05-05 FR FR7713684A patent/FR2350302A1/en active Granted
- 1977-05-05 BE BE177303A patent/BE854299A/en not_active IP Right Cessation
- 1977-11-09 FR FR7733729A patent/FR2392935A1/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7067094B2 (en) * | 2003-09-09 | 2006-06-27 | Grillo-Werke Ag | Process for the brightening of sodium hydrogensulfate |
Also Published As
| Publication number | Publication date |
|---|---|
| DE2619811C2 (en) | 1978-05-11 |
| FR2350302B1 (en) | 1983-01-14 |
| FR2350302A1 (en) | 1977-12-02 |
| BE854299A (en) | 1977-11-07 |
| FR2392935B1 (en) | 1983-01-07 |
| GB1584702A (en) | 1981-02-18 |
| IT1075526B (en) | 1985-04-22 |
| FR2392935A1 (en) | 1978-12-29 |
| JPS52133899A (en) | 1977-11-09 |
| GB1584703A (en) | 1981-02-18 |
| DE2619811B1 (en) | 1977-09-15 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed [section 19, patents act 1949] | ||
| PCNP | Patent ceased through non-payment of renewal fee |