光纤消逝波传感器测定乙醇中水含量

Determination of Low-level Water Content in Ethanol by Fiber-Optic Evanescent Absorption Sensor

采用弯曲单晶兰宝石光纤在近红外区域的消逝波传感技术,精确测定了乙醇中水的含量.应用化学计量学中的经典最小二乘法建立了消逝波红外吸收光谱的数据模型,并且用该模型预测了乙醇中水含量,预测的标准偏差为0.42%.同时给出了提高预测精确度的方法.相对于其它的传感技术,弯曲光纤消逝波传感技术具有成本低、准确度高、不易受外界干扰等优点,可望广泛应用于生物燃料加工、工业乙醇的提纯等领域的在线监测.

Evanescent field absorption spectroscopy in the infrared range of coiled fiber-optic sensor has been applied to determine the low-level water content in ethanol.Classical least square models have been utilized to build the calibration model and predict the water concentrations.The standard errors of predictions of water concentrations in ethanol was 0.42%.Some methods to improve the accuracy of predicated water concentration in ethanol were suggested.The predicted concentration of water is acceptably accurate and cost-effective.The study demonstrates that the coiled fiber-optic sensor based on evanescent absorption spectroscopy is a feasible technology for prediction of the low-level water content in bio-ethanol and other industries in both on-line and remote situation.