Isolation of 3-isopropyl-2,1,3-benzothiadiazin-4-one-2,2-dioxide from waste water from its preparation

Patent · Tue May 29 00:00:00 EDT 1984

OSTI ID:6508626

Hansen, H; Merkle, H; Mueller, A

3-Isopropyl-2,1,3-benzothiadiazin-4-one-2,2-dioxide (bentazone) is isolated from waste water, originating from its preparation and working up, by treating the waste water with an acid to bring the pH initially to 7.5-9.5, adding 0.2-0.5% by volume, based on the waste water, of a 40-60 percent strength by weight aqueous bentazone salt solution and heating the mixture for 15-30 minutes at 75/sup 0/-110/sup 0/ C. The solution thus treated is then cooled and brought to pH 1-3 with a mineral acid, whereupon the bentazone precipitates in a form which can be filtered off.

• Assignee: BASF Aktiengesellschaft (Germany, Federal Republic of)
• Patent Number(s): US 4451378
• OSTI ID: 6508626
• Resource Relation: Patent Priority Date: Priority date 14 Oct 1982, Germany, Federal Republic of (F.R. Germany); Other Information: PAT-APPL-434369
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
BENZOTHIAZOLES
FILTRATION
PRECIPITATION
WASTE WATER
ACIDIFICATION
ALKALI METAL COMPOUNDS
AMMONIUM COMPOUNDS
AQUEOUS SOLUTIONS
COOLING
HEATING
INORGANIC ACIDS
PH VALUE
AZOLES
DISPERSIONS
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
LIQUID WASTES
MIXTURES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXYGEN COMPOUNDS
SEPARATION PROCESSES
SOLUTIONS
THIAZOLES
WASTES
WATER
400105* - Separation Procedures
400301 - Organic Chemistry- Chemical & Physicochemical Properties- (-1987)