建立了热重/差热分析(TG/DTA)-剑桥滤片-吸收瓶捕集-高效液相色谱(HPLC)联用装置,将该联用装置应用于热重逸出气体中七种挥发酚物质的定量研究,并验证了其可靠性.首先在10℃/min升温速率、300mL/min的氮气流量下对烟丝进行热失重分析,根据TG和DTG曲线得到其主要热失重区间为室温～ 600℃之间,然后采用剑桥滤片-吸收瓶对该温度区间内逸出气体中的七种挥发酚物质捕集,用HPLC进行定性和定量分析.结果表明,联用装置中剑桥滤片和吸收瓶两种不同的捕集方式有选择性地捕集了逸出气体中的挥发酚物质,剑桥滤片更利于对-苯二酚、间-苯二酚、邻-苯二酚的捕集,而吸收液更利于苯酚、间,对-甲酚、邻-甲酚的捕集；同样条件下热重逸出气体中的酚类物质含量不同,苯酚和对-苯二酚的含量较高,分别为1.858、1.675mg/g;间-苯二酚的含量最低,为0.032mg/g.5次平行实验得到各挥发酚物质生成量的相对标准偏差(RSD)均在10％以内,由此验证了该联用装置的可靠性,可用于程序升温下样品裂解逸出气体中挥发酚物质的定量研究.%A new combination system of therrnogravimetry/differential thermal analysis(TG/DTA)-Cambridge filter-absorption bottle trapping unit-high performance liquid chromatography(HPLC)was established and applied to analysis the seven volatile phenols in evolved pyrolysis products and the reliability of the new system. Firstly,the main weight loss temperature(MWLT)of pipe tobacco was obtained according to the TG and DTG curves at 10 t/min heating rate and 300 mL/min of nitrogen flow,which was from room temperature to 600% , then the seven volatile phenols was trapped and analysed qualitatively and quantitatively using the combination system in MWLT. Results indicated that volatile phenols in evolved gas was trapped selectively by the two different trapping ways,Cambridge filter was more inclined to trap hydroquinone,resorcinol and catechol while absorption bottle was more inclined to trap phenol,p-cresol,m-cresol,rno-cresol. Yields of each polyphenol in evolved gas was different in the same condition:phenol and catechol was higher than others,which was 1. 858 and 1. 675 mg/g respectively;While resorcinol was the lowest,which was 0. 032 mg/g. This combination system had high reliability as the relative standard deviation(RSD)of each volatile phenol in 5 parallel experiments were all bellow 10% and it could be used to study the generation of volatile phenols in the pyrolysis process with temperature programming.
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