Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Reexamination Certificate
2007-03-06
2007-03-06
McKane, Joseph K. (Department: 1626)
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
C546S153000, C546S303000, C548S209000, C514S312000, C514S345000, C514S367000
Reexamination Certificate
active
10332105
ABSTRACT:
A process for extracting from aqueous solution the alkali metal or calcium salt of a halo or haloalkyl substituted 2-hydroxypyridine, or a 2-hydroxyquinoline or 2-hydroxybenzothiazole which comprises contacting an aqueous alkaline or neutral solution of the alkali metal or calcium salt, in which is dissolved an alkali metal fluoride, chloride, bromide, hydroxide, sulphate, sulphite, cyanate, cyanide, thiocyanate, thiosulphate, sulphide, phosphate, hydrogen phosphate, carbonate, bicarbonate, borate, chlorate, hypochlorite, perchlorate, nitrite, chromate, dichromate or permanganate or calcium chloride, bromide, nitrate, nitrite, chlorate, hypochlorite, perchlorate, thiocyanate, thiosulphate, chromate, dichtromate or permanganate, with a partially water-miscible organic solvent so as to transfer aqueous solution of the alkali metal or calcium salt of the 2-hydroxypyridine, 2-hydroxyquinoline or 2-hydroxybenzothiasole into the solvent whilst retaining separate aqueous and solvent phases, and thereafter separating the solvent phase containing the alkali metal or calcium salt and water from the aqueous phase, the ratio of solvent to water in the separated solvent phase being from 0.5:1 to 10:1 w/w.
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Forrester Julie
Hamilton Susan Thomson
Jones Raymond Vincent Heavon
Murray Joanne Emma
Stewart Alastair Iain Currie
Coppins Janet L.
Gegick Rebecca A.
McKane Joseph K.
Syngenta Limited
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