气-质联用解析热处理材显色基团

Analyzing chromogenic group of heat treated wood by GC-MS

以过热蒸汽为传热介质和保护性气体,在热处理温度为160℃、180℃、200℃、220℃,热处理时间为2h、4h、6h、8h的条件下对圆盘豆木材进行高温热处理,研究圆盘豆木材在不同热处理条件下的颜色变化规律及其变化机理。结果表明,随着热处理温度升高和热处理时间延长,圆盘豆热处理材L^(*)值降低,a^(*)值变化不大,b^(*)值降低。抽提物的紫外光谱、气-质联用分析表明,热处理使木质素和抽提物中的发色基团和助色基团发生氧化、还原反应,新生成发色基团的种类和数量增多,使木材颜色加深。

Okan wood was heat treated at temperature of 160℃,180℃,200℃,220℃ and at duration of 2h,4h,6h,8h,with the superheated steam as a heating medium and a shielding gas.The mechanism and color change of okan wood at different conditions are studied.The results show that L^(*) decreases,b^(*) reduces and the variation trend of a^(*) is obscure,with the temperature and duration increases.The UV-VIS and GC-MS analysis indicts that the heat-treatment makes the color radical and auxochromic group in the lignin and extract turn up oxidation-reduction reaction,which results in the increase of kind and amount of newly generated color radical,so that wood color grows dark.