propenal（也称为丙烯醛）是最简单的不饱和醛，在室温下以透明液体的形式存在。丙烯可以用丙烯产生，并用作化学合成或杀菌剂的试剂。
从丙烯丙烯醛产生丙烯醛后，必须使用类似于类似的过程将其与水和杂质分开Figure 1。
To evaluate the purity of the acrolein produced the acetaldehyde and water concentration in the final product must be measured. In addition, acrolein is toxic and the solvent outflows must also be monitored.
近红外光谱（NIR）可用于提供瞬时原位使用负担得起的双光束，三个波长NIR光度计分析过程，并带有光纤入流探针。该系统允许进行过程控制，这意味着可以准确控制产生的丙烯醛的水含量。
图1。丙烯醛生产过程图
背景
电磁光谱的近红外区域包含针对C-H，N-H和O-H键模模式组合带的频率。测量具有已知水浓度的丙烯醛样品的NIR光谱可以绘制校准曲线，该曲线可用于测量未来的样品并确定其水含量。
分析systems from Process Insights use fiber optic transmission, which allows the sample probe to be located in-stream, with the spectrometer itself located elsewhere.
Table 1.Water concentration
图2。Acrolein
Table 2.丙烯醛吸光度数据中的水
Experimental
一系列水浓度在2 - 6％之间的丙烯醛样品（Figure 2，，，，Table 1）用于证明测量可行性。这ClearView db photometric analyzer与过程见解一起使用10毫米流动池进行测量。
这ClearView db was equipped with filters at 1301 nm, 1432 nm, and 1744nm. These filters have been determined to be optimal for this measurement.
分析
表2显示了丙烯醛样品的吸光度数据。数据显示基于水浓度的数据良好线性。在1,301 nm处采取的数据用作基线校正，并在1,432 nm处获取的数据，并使用1,744 nm来对水的线性回归进行建模。Table 3显示结果。
确定水浓度的误差约为0.03％。图4shows the results of a similar experiment carried out for acetaldehyde concentration.
Discussion
使用NIR光度法与光纤探针一起是对丙烯醛中水和乙醛动态分析的完美方法。
Using just 1 or 2 sample points the ClearView db filter photometer, from Process Insights, can be used to measure low concentration levels of water and acetaldehyde concentration in real-time.
这原位analysis method of the ClearView db means that manual sampling of toxic acrolein does not need to occur, providing a safe and accurate method of analyzing and controlling acrolein production.
图3。水结果：Clearview DB
图4。Acetaldehyde Results: ClearView db
This information has been sourced, reviewed and adapted from materials provided by Process Insights – Optical Absorption Spectroscopy.
有关此消息来源的更多信息，请访问工艺见解 - 光吸收光谱。