Study On Measurement Technique Of Heavy Meatals And Volatile Organic Compounds In Cigarette Materials

Currently, there are no industrial standards in domestic tobacco industry for the detection of heavy metals in cigarette paper and volatile organic compounds (VOCs) in cigarette adhesive. Through a comprehensive study on the pre-treatment by microwave digestion, the graphite furnace testing conditions and the headspace gas chromatography testing conditions, a sensitive, reliable and high-efficiency method for determination of heavy metals in cigarette paper and VOCs in cigarette adhesive was established.The results of the pre-treatment of cigarette paper by microwave digestion showed that the type and dosage of the digestion agent, the dosage of cigarette paper and digestion procedures have great influences on the detection accuracy. The optimal process variables were as follows:0.300g of cigarette paper was digested by4mL HNO3+2mL H2O2+2mL H2O as the digestion agent at the maximum digesting temperature of190℃by a step temperature mode for25min. Under the optimal condition, the cigarette paper could be completely digested.The graphite furnace testing conditions of determination the contents of Pb, As, Cr in cigarette paper, such as the drying process, the ashing process, the atomization process and the cleaning process were investigated. The results showed that the ashing process and the atomization process were the main factors affecting detection accuracy. The ashing temperature, ashing time, atomatication temperature and atomatication time were optimized as700℃,3s,1900℃and3s for Pb;600℃,3s,2200℃and2s for As;800℃,3s,2300℃and2s for Cr. The matrix modifiers must be added in the ashing process to reduce the adverse effects of the matrix effect, because Pb, As, Cr were easy to volatilize at the high temperature. And the matrix modifiers of Pb, As, Cr were10μL of ammonium dihydrogen phosphate, nickel nitrate and palladium chloride, respectively.GC temperature programming, equilibrium temperature, equilibrium time and the sample dosage were investigated for determination the contents of VOCs in cigarette adhesive. The results showed that temperature programming was initial temperature of50℃ for2min, heating rate1℃/min to60℃for5min, heating rate3℃/min to120℃for5min, equilibrium temperature of100℃, equilibrium time of30min, and the sample dosage of1.00g. Under these optimal conditions the components of VOCs in cigarette adhesive could be completely separated, and the response signals value were larger. Besides, the Standard curve was made by a full evaporation technique, and this method could get rapid, high-effective, and accurate results.