Determination of Trace lignin in Flax Fiber By Turbidimetry

A new method of rapidly quantitatively analyze trace lignin in flax fiber by turbidimetry was proposed in this paper. The flax fiber was treated with 72% sulfuric acid solution and then a uniform suspension was achieved by evenly suspending the insoluble lignin in glycerin aqueous solution with ultrasonic shacking. Turbidity was measured at 660nm, and then the content of lignin was determined by the method of standard curve. The features of this method were simplicity, promptness and high accuracy. It was especially suitable for the determination of trace lignin.