Abstract:
The invention relates to a continuous method for producing nitrobenzene by nitriding benzene by means of nitric acid or mixtures of nitric acid and sulfuric acid to form raw nitrobenzene, washing the raw nitrobenzene by means of at least one acidic, alkaline, and neutral wash, respectively, wherein a prepurified nitrobenzene is obtained, comprising at least light boilers, optionally medium boilers, and high boilers and salts in addition to nitrobenzene, wherein the prepurified nitrobenzene is further purified by separating light boilers in a distillation apparatus by evaporating the light boilers and separating nitrobenzene from the further purified nitrobenzene thus obtained in a distillation apparatus by partially evaporating nitrobenzene, wherein pure nitrobenzene is removed from the distillation apparatus in gaseous form and then condensed, and wherein the non-evaporated part of the further purified nitrobenzene is fed back into the wash at an arbitrary point.
Abstract:
Die Herstellung von 2-Brom-4,6-dinitrochlorbenzol wird aus Chlorbenzol, das vorher mit einem Gemisch aus Schwefel- und Salpetersäure behandelt wird, oder aus individuellen o-, p-Nitrochlorbenzolen, oder aus einem eutektischen Gemisch von o-, p-, m-Nitrochlorbenzolen vorgenommen, indem man beliebige der genannten Stoffe bei einer Temperatur von 20 bis 120° C mit Brom oder mit Alkalimetallbromid, mit Salpetersäure oder mit Alkalimetallnitrat und mit Schwefelsäure oder mit Oleum bei folgenden Molverhältnissen der Reagenzien behandelt: Ausgangsstoff: Brom oder Alkalimetallbromid: Salpetersäure oder Alkalimetallnitrat: Schwefelsäure oder Oleum gleich 1,0:0,5-1,5 oder 1,0-3,0:2,0-4,0 oder 2,5-5,0:6,0-70,0.
Abstract:
Methods for the production of 1,1,1,-trihalogeno-2-nitroethanes from 1,1-dihalogenoethylene by using nitric acid or its salt and hydrogen chloride or hydrogen bromide or its salt, and for the production of alpha-unsaturated amines from the 1,1,1-trihalogeno-2-nitroethanes which are useful as insecticides.
Abstract:
Methods for the production of 1,1,1,-trihalogeno-2-nitroethanes from 1,1-dihalogenoethylene by using nitric acid or its salt and hydrogen chloride or hydrogen bromide or its salt, and for the production of alpha-unsaturated amines from the 1,1,1-trihalogeno-2-nitroethanes which are useful as insecticides.
Abstract:
In a process for the preparation of 3,4'-diaminodiphenyl ether, 3-nitrodiphenyl ether is reacted with a compound selected from Br 2 and HN0 3 to yield a compound of the formula: wherein R is Br or N0 2 ; and then carrying out, in any appropriate order, the steps of: (a) substituting any Br atom in the 4'-position with an NH 2 group; (b) reducing any N0 2 group to an NH 2 group.
Abstract:
La présente invention concerne un nouveau procédé de préparation du paranitrophénol par mise en contact dans l'acide fluorhydrique liquide d'un ester minéral de phényle avec un agent de nitration et en ce qu'on réalise simultanément ou successivement une hydrolyse du produit obtenu.