Invention Grant
- Patent Title: Process for acidic scrubbing of dinitrotoluene in the presence of hydrocyanic acid
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Application No.: US15031100Application Date: 2014-10-22
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Publication No.: US09688606B2Publication Date: 2017-06-27
- Inventor: Samuel Neto , Rüdiger Fritz , Renate Hempel , Holger Allardt , Yuan Shen Dai , Barbara Becker , Sebastian Ahrens , Julia Leschinski , Henrich Hermann , Mirko Haendel , Jürgen Pöhlmann
- Applicant: BASF SE , Josef Meissner GmbH & Co. KG
- Applicant Address: DE DE
- Assignee: BASF SE,Josef Meissner GmbH & Co. KG
- Current Assignee: BASF SE,Josef Meissner GmbH & Co. KG
- Current Assignee Address: DE DE
- Agency: Drinker Biddle & Reath LLP
- Priority: EP13189687 20131022
- International Application: PCT/EP2014/072633 WO 20141022
- International Announcement: WO2015/059185 WO 20150430
- Main IPC: C07C201/16
- IPC: C07C201/16 ; C07C205/06 ; B01D11/04 ; C02F1/20 ; C02F1/26 ; C02F3/00 ; B01D11/00 ; C02F101/18 ; C02F103/36

Abstract:
Process for scrubbing a crude mixture which is obtained in the nitration of toluene after separating off the nitrating acid and comprises dinitrotoluene, nitric acid, nitrogen oxides and sulfuric acid, which comprises two scrubbing steps (WS-I) and (WS-II), whereini) in a first scrubbing step (WS-I), the crude mixture is extracted with a scrubbing acid I comprising nitric acid, nitrogen oxides and sulfuric acid in a scrub comprising at least one extraction stage, where the scrubbing acid discharged from the first extraction stage (WS-I-1) of the first scrubbing step (WS-I) has a total acid content of from 10 to 40% by weight and a content of from 80 to 350 ppm of hydrocyanic acid, giving a prescrubbed crude mixture,ii) in a second scrubbing step (WS-II), the prescrubbed crude mixture comprising dinitrotoluene is extracted with a scrubbing acid II in a scrub comprising at least one, preferably at least 2, extraction stage(s), where the scrubbing acid discharged from the first extraction stage (WS-II-1) of the second scrubbing step (WS-II) has a pH of less than or equal to 4, giving a dinitrotoluene-comprising mixture which is essentially free of nitric acid, sulfuric acid, nitrogen oxides and hydrocyanic acid and has a content of not more than 300 ppm of nitric acid and nitrogen oxides, not more than 3 ppm of sulfate and not more than 50 ppm of hydrocyanic acid.
Public/Granted literature
- US20160251302A1 PROCESS FOR ACIDIC SCRUBBING OF DINITROTOLUENE IN THE PRESENCE OF HYDROCYANIC ACID Public/Granted day:2016-09-01
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