Method for the purification of triorganophosphites by treatment with a basic additive
View Patent ↗One or more triorganophosphite components are separated from a crude phosphite mixture containing acidic hydrolysis products. The crude phosphite mixture is contacted with a basic additive to produce a second mixture comprising a first phase and a second phase. The first phase comprises the basic additive and one or more acidic hydrolysis products and the second phase comprises one or more triorganophosphite components.
1. A method for preparing triorganophosphites, said method comprising:
a) contacting an alcohol with PCl 3 in the presence of a triorganoamine to produce a first reaction product comprising one or more organophosphites and triorganoamine hydrochloride;
b) removing the triorganoamine hydrochloride from the first reaction product to produce a second reaction product optionally containing one or more triorganophosphites, diorganohydrogenphosphite (R 2 O)(R 3 O)POH, organodihydrogenphosphite (R 1 O)(HO)PO(H) and H 3 PO 3 , wherein R 1 , R 2 and R 3 are independently selected from the group consisting of C 1 to C 18 alkyl, C 6 to C 18 aryl and hydroxyaryl, and C 3 to C 18 cycloalkyl and hydroxyalkyl radicals, and wherein R 2 and R 3 can optionally be connected to each other directly by a chemical bond or through an intermediate divalent group R 9 , wherein R 9 is selected from the group consisting of —O—, —S—, and —CH(R 12 )—, wherein R 12 is selected from the group consisting of H, C 6 to C 18 aryl, and C 1 to C 18 alkyl; and
c) removing at least a portion of one or more of the compounds diorganohydrogenphosphite (R 2 O)(R 3 O)POH, organodihydrogenphosphite (R 1 O)(HO)PO(H) and H 3 PO 3 by contacting the second reaction product with a basic additive.
2. The method of claim 1 , wherein the basic additive comprises at least one compound selected from the group consisting of NaOH, KOH, Na 2 CO 3 , K 2 CO 3 , Ca(OH) 2 , NH 4 OH, CaCO 3 , a basic ion-exchange resin, and combinations thereof.
3. The method of claim 1 , wherein step c) is repeated.