Determination of Saturated Fatty Acids in Fatliquoring Agent by Capillary Gas Chromatography

A method for determination of palmitic acid and stearic acid in leather fatliquoring agent was developed using the capillary gas chromatography(GC).Before GC analysis,the grease samples were firstly saponified and acidified.The calibration curves(A=495.18C-14.9(R~2=0.998 1,n=7))for palmitic acid and A=429.8C-36.4(R~2=0.995 7,n=7)for stearic acid are found to be linear within the range of 0.1～2.0mg/mL and the detection limit are 42.7ng for palmitic acid and 77.6ng for stearic acid(S/N=3).The relative standard derivations(RSD) are 0.76%(n=7) for palmitic acid and 1.75%(n=7)for stearic acid and their average recoveries are 93.1%(RSD=3.4%,n=3)and 89.4%(RSD=4.8%,n=3)respectively.The method can be used for tanneries to monitor the saturated fatty acids in fatliquoring agent to avoid fatty spew.