CS233242B1 - Method of 2,2-hydrazobisizobutyronitrile making - Google Patents
Method of 2,2-hydrazobisizobutyronitrile making Download PDFInfo
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- CS233242B1 CS233242B1 CS837353A CS735383A CS233242B1 CS 233242 B1 CS233242 B1 CS 233242B1 CS 837353 A CS837353 A CS 837353A CS 735383 A CS735383 A CS 735383A CS 233242 B1 CS233242 B1 CS 233242B1
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- hydrazine
- acetone cyanohydrin
- concentrated
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- sulfate
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- 238000000034 method Methods 0.000 title claims description 7
- MWFMGBPGAXYFAR-UHFFFAOYSA-N 2-hydroxy-2-methylpropanenitrile Chemical compound CC(C)(O)C#N MWFMGBPGAXYFAR-UHFFFAOYSA-N 0.000 claims abstract description 32
- OAKJQQAXSVQMHS-UHFFFAOYSA-N Hydrazine Chemical compound NN OAKJQQAXSVQMHS-UHFFFAOYSA-N 0.000 claims abstract description 24
- FUSNOPLQVRUIIM-UHFFFAOYSA-N 4-amino-2-(4,4-dimethyl-2-oxoimidazolidin-1-yl)-n-[3-(trifluoromethyl)phenyl]pyrimidine-5-carboxamide Chemical compound O=C1NC(C)(C)CN1C(N=C1N)=NC=C1C(=O)NC1=CC=CC(C(F)(F)F)=C1 FUSNOPLQVRUIIM-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000012493 hydrazine sulfate Substances 0.000 claims abstract description 11
- 229910000377 hydrazine sulfate Inorganic materials 0.000 claims abstract description 11
- 239000002699 waste material Substances 0.000 claims abstract description 9
- NWZSZGALRFJKBT-KNIFDHDWSA-N (2s)-2,6-diaminohexanoic acid;(2s)-2-hydroxybutanedioic acid Chemical compound OC(=O)[C@@H](O)CC(O)=O.NCCCC[C@H](N)C(O)=O NWZSZGALRFJKBT-KNIFDHDWSA-N 0.000 claims abstract description 8
- IKDUDTNKRLTJSI-UHFFFAOYSA-N hydrazine monohydrate Substances O.NN IKDUDTNKRLTJSI-UHFFFAOYSA-N 0.000 claims abstract description 8
- 238000002360 preparation method Methods 0.000 claims abstract description 6
- HOSVESHQDSFAST-UHFFFAOYSA-N 2-[2-(2-cyanopropan-2-yl)hydrazinyl]-2-methylpropanenitrile Chemical compound N#CC(C)(C)NNC(C)(C)C#N HOSVESHQDSFAST-UHFFFAOYSA-N 0.000 claims description 8
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims 3
- 238000004519 manufacturing process Methods 0.000 abstract description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 7
- OVARTBFNCCXQKS-UHFFFAOYSA-N propan-2-one;hydrate Chemical compound O.CC(C)=O OVARTBFNCCXQKS-UHFFFAOYSA-N 0.000 abstract description 2
- -1 acetone cyanohydrin hydrazine hydrate Chemical compound 0.000 abstract 1
- 239000007858 starting material Substances 0.000 abstract 1
- OZAIFHULBGXAKX-UHFFFAOYSA-N 2-(2-cyanopropan-2-yldiazenyl)-2-methylpropanenitrile Chemical compound N#CC(C)(C)N=NC(C)(C)C#N OZAIFHULBGXAKX-UHFFFAOYSA-N 0.000 description 8
- 239000000243 solution Substances 0.000 description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- VVQNEPGJFQJSBK-UHFFFAOYSA-N Methyl methacrylate Chemical compound COC(=O)C(C)=C VVQNEPGJFQJSBK-UHFFFAOYSA-N 0.000 description 5
- 239000012043 crude product Substances 0.000 description 5
- 239000000203 mixture Substances 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 239000011541 reaction mixture Substances 0.000 description 4
- 238000009833 condensation Methods 0.000 description 3
- 230000005494 condensation Effects 0.000 description 3
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- ZGCHATBSUIJLRL-UHFFFAOYSA-N hydrazine sulfate Chemical compound NN.OS(O)(=O)=O ZGCHATBSUIJLRL-UHFFFAOYSA-N 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical compound [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 description 2
- 241000220479 Acacia Species 0.000 description 1
- 239000004604 Blowing Agent Substances 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 235000010643 Leucaena leucocephala Nutrition 0.000 description 1
- 229910019093 NaOCl Inorganic materials 0.000 description 1
- 239000005708 Sodium hypochlorite Substances 0.000 description 1
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 239000007900 aqueous suspension Substances 0.000 description 1
- XOZUGNYVDXMRKW-AATRIKPKSA-N azodicarbonamide Chemical compound NC(=O)\N=N\C(N)=O XOZUGNYVDXMRKW-AATRIKPKSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 244000309464 bull Species 0.000 description 1
- 239000004202 carbamide Substances 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000003999 initiator Substances 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000002574 poison Substances 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Vynález rieSl výrobu,2,2 -hydrazobislzobutyronitrilu z acetonkyanhydrínu a hydrazínsulfátu, hydrazínhydrátu připadne z volného hydrazínu. Pri tejto výrobě sa ako východisková suřqviňa použije okrem koncentrovaného acetonkyanhydrínu odpadný nízkokoncentrovaný acetonkyanhydrín a/alebo vodou zriedený o koncentrácii acetonkyanhydrínu vo vodě 1 až 97 % hmot., pričom celkový mólový poměr koncentrovaného a odpadného nízkokoncen^rováného a/alebo vodou zriedeného acetonkyanhydrínu k hydrazínsulfátu připadne hydrazínhydrátu alebo volnému hydrazínu je 2:1.The present invention provides for the preparation of 2,2-hydrazobisobutyronitrile from acetone cyanohydrin a hydrazine sulfate, hydrazine hydrate from free hydrazine. In this production used as starting material except of concentrated acetone cyanohydrin low concentration acetone cyanohydrin and / or water diluted with acetone cyanohydrin in water 1 to 97 wt total mole ratio of concentrated a low-grade waste and / or water-diluted acetone cyanohydrin hydrazine hydrate to hydrazine sulfate or free hydrazine is 2: 1.
Description
Vynález se týká spčsobu výroby 2,2'-hydrazobisizobutyronitrilu, mediiproduktu pre výrobu 2,2'-azobisizobutyronitrilu, z odpadného a/alebo nízkokoncentrovaného acetónkyanhydrínu.The invention relates to a process for the preparation of 2,2'-hydrazobisisobutyronitrile, an intermediate for the preparation of 2,2'-azobisisobutyronitrile, from waste and / or low-concentration acetone cyanohydrin.
V súčasnej době sa 2,2'-hydrazobisizobutyronltril připravuje z koncentrovaného acetónkyanhydrlnu a hydražinu, hydrazínsulfátu alebo hydrazínhydrétu. 2,2'-hydrazobisIzobutyronitril sa připravuje buá tak, že sa připravuje hydrazín v reakčnej zmesi bez izolácie z NaOH, chlóru a močoviny. Na hydrazín (obsahuje ešte nezreagovanú aačovinu, NaOH, NaOCl, NaCl) sa pfisobí acetónkyanhydrínom o koncentrácii 97 % hmot. a vyššej.Currently, 2,2'-hydrazobisisobutyronitrile is prepared from concentrated acetone cyanohydrin and hydrazine, hydrazine sulfate or hydrazine hydrate. The 2,2'-hydrazobisisobutyronitrile is prepared either by preparing the hydrazine in the reaction mixture without isolation from NaOH, chlorine and urea. Hydrazine (containing unreacted acacia, NaOH, NaOCl, NaCl) is treated with 97% w / w acetone cyanohydrin. and higher.
(čs. pat. 122 204).(U.S. Pat. No. 122,204).
Běžným spčsobom přípravy je kondenzécia hydrazínu, hydrazínhydrétu alebo hydrazínsulfátu s acetónkyauhydrínom, pričom čistota použitého acetónkyanhydrínu je lepšla ako 97 % hmot. /Minatoyo K.: Bull, Rub. Res. Inst. Japan, No 1, 7-12 (1945); Overberger Q. O., Berenbaum Μ. B.: J. Amer. Chem. Soc. 73. 2 618-2 625 (1951)/.A conventional preparation is the condensation of hydrazine, hydrazine hydrate or hydrazine sulfate with acetone cyanohydrin, the purity of the acetone cyanohydrin used being better than 97% by weight. / Minatoyo K .: Bull, Rub. Res. Inst. Japan, No. 1, 7-12 (1945); Overberger Q. O., Berenbaum Μ. B .: J. Amer. Chem. Soc. 73. 2,618-2,625 (1951)].
Pri tomto spčsobe sa používá acetónkyanhydrín o koncentrácii lepšej ako 97 % hmot., čo vylučuje možnost využitie odpadného nízkokoncentrovaného acetónkyanhydrínu, ktorý je hlavnou surovinou najma pri výrobě metylmetakrylátu. Pri výrobě metylmetakrylétu je acetónkyanhydrín o koncentrácii nižšej ako 97 % hmat. ťažko použitelný, nakolko technologie výroby metylmetakrylátu potřebuje acetónkyanhydrín bezvodý, príp. s obsahom ped 0,5 % hmot.Acetone cyanohydrin with a concentration better than 97% by weight is used in this process, eliminating the possibility of using low-concentrated acetone cyanohydrin, which is the main raw material, especially in the production of methyl methacrylate. In the production of methyl methacrylate, acetone cyanohydrin is less than 97% tactile. difficult to use, since the methyl methacrylate production technology needs acetone cyanohydrin anhydrous, resp. containing 0,5% or more by weight
Pri výrobě acetónkyanhydrínu, ako i pri jeho manipulácii u výrobců metylmetakrylétu je často k dispozici! acetónkyanhydrín zriedený vodou a tým nepoužitelný pre výrobu metylmetakrylátu. Acetónkyanhydrín je prudký jed, a preto je potřebné odpadný i nízkokoncentrovaný acetónkyanhydrín buá ekonomicky využit alebo zlikvidovat. Jeho likvidécia je však obtiažna a náročná z ekologického hladiska. Likviduje sa napr. vodným roztokom chlornanu sodného, přitom je nevýhodné, že sa ničia suroviny, ktoré by mohli priniest ekonomický efekt.It is often available in the production of acetone cyanohydrin as well as its handling at methyl methacrylate manufacturers! acetone cyanohydrin diluted with water and thus not usable for the production of methyl methacrylate. Acetone cyanohydrin is a violent poison and therefore both waste and low-concentration acetone cyanohydrin need to be economically used or disposed of. However, its liquidation is difficult and demanding from an environmental point of view. Disposed eg. with an aqueous solution of sodium hypochlorite, but it is disadvantageous that the raw materials which could have an economic effect are destroyed.
Podla tohto vynálezu sa spčsob výroby 2,2'-hydrazobisizobutyronitrilu z acetónkyanhydrínu a hydrazínsulfátu, hydrazínhydrátu připadne z volného hydrazínu uskutočňuje tak, že ako východisková surovina sa okrem koncentrovaného acetónkyanhydrínu použije odpadný nízkokoncentrovaný aceto'nkyanhydrin a/alebo vodou zriedený o koncentrácii acetónkyanhydrínu vo vodě 1 až 97 % hmot., pričom celkový mólový poměr koncentrovaného a odpadného nízkokonoentrovaného a/alebo vodou zriedeného acetónkyanhydrínu k hydrazínsulfátu připadne hydrazínhydrátu alebo volnému hydrazínu je 2:1.According to the present invention, a process for the preparation of 2,2'-hydrazobisisobutyronitrile from acetone cyanohydrin and hydrazine sulfate, hydrazine hydrate optionally from free hydrazine, is carried out by using low-concentrated acetone cyanohydrin waste water and / or water acetone diluted with water up to 97% by weight, wherein the total molar ratio of concentrated and waste low-concentration and / or water-diluted acetone cyanohydrin to hydrazine sulfate or hydrazine hydrate or free hydrazine is 2: 1.
Výhodou navrhovaného spčsobu výroby je využitie odpadných vodných roztokov aoetónkyanhydrínu pře syntézu 2,2'-hydrazobisizobutyronitrilu, ktorý je medziproduktom pre výrobu 2,2'-azobisizobutyronitrilu, velmi žiadaného iniciátora připadne nadúvadla pre plastické látky. Taktiež je výhodné, že po nahromadění určitého množstva inak nepoužitelného acetónkyanhydrínu nie je ho potřebné komplikované likvidovat, ale sa výhodné ekonomicky spracuje. Ďalšou výhodou je skutočnosť, že pre výrobu 2,2'-hydrazoblsizobutyronitrilu nie sú potřebné Speciálně zariadenia, nakolko postup je možné uskutečnit v bežnom 2ariadení používanom napr. na výrobu 1,1'-azobisformamidu.The advantage of the proposed process is the use of waste aqueous solutions of oetone cyanohydrin for the synthesis of 2,2'-hydrazobisisobutyronitrile, which is an intermediate for the production of 2,2'-azobisisobutyronitrile, a highly desired initiator or plastic blowing agent. It is also advantageous that after the accumulation of a certain amount of otherwise unusable acetone cyanohydrin, it is not necessary to dispose of it in a complicated manner, but is advantageously economically processed. A further advantage is the fact that no special equipment is required for the production of 2,2'-hydrazoblsisobutyronitrile, since the process can be carried out in a conventional equipment used e.g. for the production of 1,1'-azobisformamide.
Podstata vynálezu je v spracovaní odpadného nízkokoncentrovaného acetónkyanhydrínu s hydrazínsulfátom, připadne hydrazínhydrátom alebo volným hydrazínom. V případe síranu hydrazínu sa tento uvolňuje do roztoku pomocou sody tak, aby roztok nedosiahol alkalické oblasti. Pridávanie sody k zmesi odpadného acetónkyanhydrínu sa ukončí pri pH = 6 až 7. Potom sa nadávkuje tol’ko čistého acetónkyanhydrínu, kol’ko třeba z mólového poměru na naseděný hydrazín. Reakčné zmes sa refluxuje 20 h, odsaje, premyje a použije sa na oxidáciu produktu, ktorým je 2,2'-azobisizobutyronítril.SUMMARY OF THE INVENTION The present invention is in the treatment of waste low-concentration acetone cyanohydrin with hydrazine sulfate, optionally hydrazine hydrate or free hydrazine. In the case of hydrazine sulfate, this is released into the solution by means of soda so that the solution does not reach the alkaline region. The addition of soda to the waste acetone cyanohydrin mixture is terminated at pH = 6-7. Thereafter, as much pure acetone cyanohydrin is metered in as necessary from the molar ratio to the mounted hydrazine. The reaction mixture is refluxed for 20 h, filtered off with suction, washed and used to oxidize the 2,2'-azobisisobutyronitrile product.
Příklad, 1Example, 1
Do 2,5 1 baňky vybavenéj miešadlom, teplomerom, deliacim lievikom a spatným chladičom sa nasadí 1 000 ml 5 %-ného roztoku acetónkyanhydrínu (So představuje 50 g, 0,59 molu acetónkynahydrínu v roztoku). Ďalej sa přidá 200 g (1,53 molu) síranu hydrazínu a po jeho rozpuštění sa pomaly přidává 237,1 g (2,38 molu) bezvodého NagCO^ tak, aby teplota zmesi nevystúpila nad 30 °C. Potom sa zmes vyhřeje na 30 °C a přidá sa 212,4 g (2,5 molu) koncentrovaného 97 %-náho acetónkyanhydrínu.A 2.5 L flask equipped with a stirrer, a thermometer, a separatory funnel, and a reflux condenser was charged with 1000 mL of 5% acetone cyanohydrin solution (S0 represents 50 g, 0.59 moles of acetone cyanohydrin in solution). Next, 200 g (1.53 mol) of hydrazine sulphate are added and after dissolution, 237.1 g (2.38 mol) of anhydrous NagCO3 are slowly added so that the temperature of the mixture does not rise above 30 ° C. The mixture was then heated to 30 ° C and 212.4 g (2.5 mol) of concentrated 97% acetone cyanohydrin was added.
Dávkuje sa 2 h pri 30 °C. Reakčná zmes sa pri tejto teplote mieša 20 h. Po odfiltrovaní sa surový produkt premyje 2 x 200 ml studenej vody. Surový produkt sa suší vo vákuovej sušiarni pri 40 °C. Získá sa 215 g (86 % na teóriu) 2,2'-hydrazobislzobutyronitrilu o t.t. 90 až 93 °C (prekryštalizevaním z éteru sa získá produkt o t.t. 93,5 až 94,5 °C). Surový produkt sa oxiduje 30 %-ným roztokom HgO2 na 2,2'-azobisizobutyronitrilu-Genitron AZDN.It is dosed at 30 ° C for 2 h. The reaction mixture was stirred at this temperature for 20 h. After filtration, the crude product is washed with 2 x 200 ml cold water. The crude product is dried in a vacuum oven at 40 ° C. 215 g (86% of theory) of 2,2'-hydrazobis-isobutyronitrile of m.p. 90 DEG-93 DEG C. are obtained (recrystallization from ether to give the product of mp 93.5 DEG-94.5 DEG C.). The crude product was oxidized with a 30% HgO 2 solution to 2,2'-azobisisobutyronitrile-Genitron AZDN.
Příklad 2Example 2
Do kondenzačněj aparatúry podTa příkladu 1 sa nasadí 524,8 g 50 %-ného roztoku acetónkyanhydrínu (obsahuje 262,4 g acetónkyanhydrínu - 3,08 molu) a 738 g vody. Potom sa přidá 200 g (1,53 molu) síranu hydrazínu tak, aby teplota nevystúpila nad 30 °G.524.8 g of a 50% solution of acetone cyanohydrin (containing 262.4 g of acetone cyanohydrin - 3.08 mol) and 738 g of water are charged to the condensation apparatus of Example 1. Then 200 g (1.53 mol) of hydrazine sulfate are added so that the temperature does not rise above 30 ° C.
Pe jeho rozpuštění sa pomaly přidává 237,1 g bezvodého NagCO^ tak, aby teplota nevystúpila nad 30 °c. Potom sa reakčná zmes mieša pri tejto teplote 20 h.To dissolve it, slowly add 237.1 g of anhydrous NagCO 3 so that the temperature does not rise above 30 ° C. The reaction mixture was then stirred at this temperature for 20 h.
Po odfiltrovaní surového produktu a po jeho sušení (ako v příklade 1) sa získá 219 g (88,4 % na teóriu) 2,2'-hydrazobisizobutyronitrilu o t. t. 90 až 92 °C. Tento surový produkt sa áalej oxiduje vo vodnej suspenzi! 30 %-ným roztokom HgOg na 2,2'-azobisizobutyronitril.After filtering off the crude product and drying it (as in Example 1), 219 g (88.4% of theory) of 2,2'-hydrazobisisobutyronitrile of m.p. t. Mp 90-92 ° C. This crude product is further oxidized in an aqueous suspension! 30% HgOg solution to 2,2'-azobisisobutyronitrile.
Přiklaď 3Example 3
Do kondenzačnej aparatúry podTa příkladu 1 sa nasadí 1 000 g vody«a 200 g síranu hydrazínu (1,53 málu). Potom sa přidá 237,1 g bezvodého NagCO^ tak, aby teplota nevystúpila nad 30 °C. Ďalej sa přidá pomaly 271 g (97 %-ného acetónkyanhydrínu- 3^09 molu) a zmes sa mieša 20 h pri 30 eC. Ďalšie spracovanie produktu je zhodné s příkladem 1. Získá sa 220 g (89 % na teórih) produktu o t. t. 90 až 92 °C. Produkt sa použije na oxidáciu k výrobě 2,2'-azobisizobutyrenitrilu.1000 g of water and 200 g of hydrazine sulphate (1.53 m) are charged to the condensation apparatus of Example 1. Then 237.1 g of anhydrous NagCO3 was added such that the temperature did not rise above 30 ° C. It is further added slowly 271 g (97% strength acetónkyanhydrínu- ^ 3 09 mole) and the mixture was stirred for 20 hours at 30 e C. The further treatment of the product was identical to Example 1 to give 220 g (89% of the teórih) of the mp 90-92 ° C. The product was used for oxidation to produce 2,2'-azobisisobutyrenitrile.
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| Application Number | Priority Date | Filing Date | Title |
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| CS837353A CS233242B1 (en) | 1983-10-07 | 1983-10-07 | Method of 2,2-hydrazobisizobutyronitrile making |
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| Application Number | Priority Date | Filing Date | Title |
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| CS837353A CS233242B1 (en) | 1983-10-07 | 1983-10-07 | Method of 2,2-hydrazobisizobutyronitrile making |
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| CS735383A1 CS735383A1 (en) | 1984-05-14 |
| CS233242B1 true CS233242B1 (en) | 1985-02-14 |
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