US EPA

2299675 

Technical Report 

Analysis of Organotin Stabilizers 

Neubert, G; Wirth, HO 

1975 

NIOSH/00133926 

273 

1 

19-23 

A chromatographic procedure for the determination of alkyltin compounds was developed. The compounds were alkylated with Grignard reagents to form a mixture of tetraalkyltins. The mixture was then injected into gas chromatographs operating at 100 to 230 degrees-C. The instruments were calibrated with tetraalkyltin compounds obtained by reaction of monobutyltin-chloride (1118463), dibutyltin-chloride (683181), tributyltin-chloride (1461229), and octyltin-chloride (3091256) with methylmagnesium-chloride. Mixtures of alkyltin halides were analyzed by alkylating a sample containing approximately 0.005 to 0.01 molar solutions of tin in 50 milliliters dry diethyl-ether. After the reaction was completed, the ether was removed, and the resulting tetraalkyltins were isolated and injected into the chromatographs. The procedure was also used to analyze mixtures of alkyltin oxides. The compound was reacted with methylmagnesium-chloride and the products were adsorbed on a silica gel column. The column was washed with n-pentane, which eluted the alkyltin. The alkyltin was then analyzed by the chromatographs. Results of analyses by this method agreed very favorably with those obtained by thin layer chromatography (TLC). The authors conclude that this procedure is superior to TLC because any type of alkyltin compound can be analyzed, it requires no difficult manual operations, and it does not depend on the difficult task of distinguishing shades of colors in TLC. (German)