The invention discloses a method for measuring residual quantity of
sodium isethionate
raw material in
sodium cocoyl isethionate, which comprises the following steps of: masking
sodium cocoyl isethionate by using
barium chloride, reacting
barium chloride with
sodium cocoyl isethionate to form a precipitate, filtering to remove
sodium cocoyl isethionate in a sample, and measuring the residual quantity of
sodium cocoyl isethionate raw material in sodium cocoyl isethionate. Then,
ammonium ceric
nitrate and
sodium isethionate are subjected to a complex reaction, quantification is carried out through an
ultraviolet-visible spectrophotometric method according to
color changes, the consumption condition of
ammonium ceric
nitrate can be judged, and therefore the content of
sodium isethionate is indirectly calculated. According to the present invention, the
ultraviolet-visible
spectrophotometry is adopted to perform quantitative detection, the
relative standard deviation of the result is less than 5%, the precision is high, the analysis test method is simple, the
pollution is low, and the time consumption is short. According to the method, multiple groups of parallel test results are close, the
repeatability is relatively good, and the accuracy is relatively high. The
recovery rate is 95-105%, and the
recovery rate is stable.