IC Determination of Sulfur and Chlorine in Solid Biomass Fuel with Tube Furnace Combustion

The crushed sample of solid biomass fuel was taken in the porcelain boat of tube furnace. After combustion, the gas was absorbed by the absorbing liquid. The absorption solution was diluted to 5.0 mL with water, and then filtered on 0.45 μm filtering membrane. IC was applied to the determination of sulfur and chlorine in the filtrate. Dionex IonPac AS18 anionic chromatographic column was used for chromatographic separation. 12 mmol·L^-1 potassium hydroxide solution was used as mobile phase, and conductance detector was used in determination. Linear relationships between values of peak area and mass concentration of sulfate and chloride were kept in the range of 0.1-10.0 mg·L^-1, with detection limit (3S/N) of 0.005, 0.003 mg·L^-1, respectively. Precision of the method was tested at the mass concentration level of 5.0 mg·L^-1 mixed standard solution of sulfate and chloride for 6 parallel determinations, and values of RSDs (n=6) of peak area of sulfate and chloride were 2.1%, 2.2%, respectively. On the base of blank sample of solid biomass fuel, test for recovery was made by standard addition method; values of recovery found were in the range of 96.0%-98.2%. The proposed method was applied to the analysis of samples of solid biomass fuel, giving results in consistency with values given by Eschkal method and potentiometric titration with high temperature hydrolysis.