Toshio Nagai

Rapid quantitative HPLC analysis of polyethoxylated nonionics

A rapid quantitative HPLC method for alkylethoxylate was studied. According to theoretical considerations based on the plate theory, it was expected that alkylethoxylate could be separated to give one chromatographic peak regardless of the carbon number distribution in hydrophobic moiety and adducted number of ethylene oxide by using a back flush technique.As expected, a single peak with good shape for quantitative use was obtained. Quantitative analytical methods were developed for (i) unconverted alkylethoxylate in alkylethoxysulfate, and (ii) alkylethoxylate nonionics formulated with anionics in detergents.As anionics generally were retained less than alkylethoxylates under the condition in which ODS-column and a methanolic aqueous eluent were used, a single peak for alkylethoxylates was obtained by back flushing after anionics were eluted from the column. In the case of a heavy duty detergent, an additional column was needed to remove the interferences owing to co-existing more retained species.

Gas chromatographic analysis for alpha-olefin sulfonate

The separation and determination of alkene sulfonate and hydroxyalkane sulfonate, and the carbon chain distribution of the lipophilic groups of long chain alpha-olefin sulfonates (C14 to C18) were studied by means of gas chromatography. Samples were hydrogenated initially, and converted to sulfonyl chlorides for gas chromatographic analysis. Using a glass column, 4 mm i.d. and 2.5 m long, packed with Silicon SE-30, 3% on 60 to 80 mesh Chromosorb WAW treated with hexamethyldisilazane, a 0.3 to 0.6 μl sample, as 10% carbon tetrachloride solution, was injected directly on the column, and alkane and monochloroalkane sulfonyl chloride were determined as alkyl chloride and alkyl dichloride, respectively. Minimization of further decomposition, improvement of peak separation and reproducibility were accomplished by this procedure. The method was applied to alpha-olefin sulfonates produced commercially from C14 to C18 alpha-olefins.

Rapid determination of sodium hydroxylalkanesulfonate in α-olefin sulfonate by NMR spectroscopy

The rapid determination of sodium hydroxylalkanesulfonate in α-olefin sulfonate (AOS) was investigated by means of NMR spectroscopy; this led to a convenient method for routine analysis of AOS.From comparison of NMR spectrum of sodium C16-3-hydroxylalkanesulfonate with that of sodium C11-2-alkenesulfonate, any specific signal easily accessible for the determination could not be found. Therefore, in order to eliminate the influence of double bond, the hydrogenation of sodium C11-2-alkenesulfonate was carried out with the ordinary manner using Pd/C catalyst. NMR spectrum of the hydrogenated product turned out to have a very simple pattern(See Fig. 2) in which only one signal based on CH2-SO3 proton appeared in the 2.44.0 ppm region. Authors found that sodium hydroxylalkanesulfonate in AOS was able to be determined by using the signals of CH2-SO3 at 2.73.1 ppm and CH-O at 3.43.7 ppm.By using this method, sodium C16-3-hydroxylalkanesulfonate in mixtures of sodium C16-3-hydroxylalkanesulfonate and sodium C11-2-alkenesulfonate was determined accurately and rapidly over a wide range (6.390.2 mol%).

Evaluation method for agglomerating properties of granular detergents

A new method for evaluating the agglomerating property of granular detergents was devised. It is useful for comparing commercial products, screening new products, and for studying anticaking agents. This method differs from prior methods, as detergent is fluidized by conditioned air in a reverse conical tower, and agglomeration is evaluated from the lowering of level of fluidized particles because of agglomeration. The height of the fluidized particles is inversely proportional to particle size, and the level of fluidized particles becomes lower more rapidly with ease of agglomeration. The coefficient of variation (σ/−x) of the method is about 10%, and it is shown that the method coincides with the tendency of detergents to agglomerate in the carton.