利用傅里叶变换红外光谱法快速测定木材纤维素含量

Rapid determination on cellulose content of wood by using FTIR spectrometry

纤维素是木材细胞壁的骨架物质,纤维素的含量不仅决定木材的性质,而且在木材的功能性改良方面对于木材的改性是非常重要的量化指标。传统纤维素含量的测定方法具有测定时间长、耗费药品且操作复杂等缺点。本论文基于傅里叶变换红外光谱(FTIR)分析测定木材中纤维素含量。以硫氰化钾为内标物,制备数个不同纤维素浓度的溴化钾片,然后以纤维素峰强度与硫氰化钾(内标物)峰强度比值对样品百分浓度作出工作曲线。不同木材的木粉与含有硫氰化钾的溴化钾粉压片后进行测量,根据混合物中纤维素特征峰强度与硫氰化钾峰强度比值,就可以从工作曲线上得到混合物中纤维素的百分含量,从而得到木材中纤维素的百分含量。试验结果表明:傅里叶变换红外光谱仪可以实现快速测定木材纤维素的含量。

Cellulose is the skeleton material of the wood cell wall, the content of cellulose is not only deciding the nature of the wood, but also an important quantitative indicator for wood＇s modification in functional improvement of wood. The traditional method for determination of cellulose content has some disadvantages, such as long test time; taking much medicine, complex and so on. This paper based on the Fourier transform infrared spectrometry（FTIR＇） to analyze the cellulose content of wood, then using potassium thiocyanate as internal standard to make several pieces of potassium bromide tablets containing different mass fraction of cellulose. Working curves were prepared by plotting the ratio of peak strength of cellulose to that of potassium thiocyanate（internal standard） versus content of cellulose. Measure the tablets that were composed of different wood＇s powder, potassium thiocyanate and potassium bromide. According to the ratio of peak strength of cellulose and that of potassium thiocyanate, can get the percentage of mixture of cellulose from the working curves; also get the percentage of cellulose of wood. The experimental results show that the Fourier transform infrared spectrometry can realize rapid determination of cellulose content of wood.