Alkane monosulphonate

This section describes methods for total alkane sulphonates, extraction and determination of mean molecular weight of alkane monosulphonates and separation and determination of alkane mono- and disulphonic acids. 

Determination of mean molecular weight of alkane monosulphonates... 

Alkane monosulphonates cannot be extracted from an acid medium by a simple separating-funnel technique because they are not sufficiently soluble in hydrocarbon solvents, the distribution coefficient between pentane and aqueous alcohol being only 0.08-0.09. Extraction with diethyl ether, which is effective for other monosulphonates, has apparently not been reported, but may be practicable. 

Weigh a sample containing 0.6-0.8g alkane monosulphonate in a 150 ml beaker. 

ISO 6845 1989 Surface active agents— Technical alkane sulfonates— Determination of the mean relative molecular mass of the alkane monosulfonates and the alkane monosulphonate content. International Organization for Standardization, Geneva. 

Separation of positional isomers of alkane monosulphonates is described in [23]. Baseline separations were obtained using Hypersil ODS I phase with acetonitrile/water gradient and A-methylpyridinium chloride as the visualisation reagent for indirect photometric detection. 

Part 2.2 Mean molecular weight and alkane monosulphonate content by extraction 6845... 

Part 2.3 Alkane monosulphonate content by two-phase titration 6121... 

Many monosulphonates can be extracted from 3 M hydrochloric acid with diethyl ether. Disulphonates and hydrotropes which are low-molecular-weight sulphonates are not extracted. In the case of a-olefin sulphonates the hydroxyalkane sulphonates are converted to sultones and extracted with the monosulphonic acid. The method is applicable to alkylbenzene sulphonates, mono- and dialkylsulphosuccinates and a-olefin sulphonates, but apparently not to alkane sulphonates. 

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