Porapak QS填充柱 气相色谱法测定粮食中的水分

气相色谱法测定粮食中的水分，液化石油气，二甲醚，甲缩醛，乙缩醛，乙醇，室内空气，焦炉煤气，炼厂气，天然气，变压器油，多氯联苯，植物油，6号溶剂残留，裂解进样器，消毒剂

气相色谱法测定粮食中的水分
气相色谱法测定粮食中的水分 详细信息：


名称：填充柱
规格：2m*3mm
型号：Porapak QS
应用： 气相色谱法测定粮食中的水分

滕州市浩瀚色谱仪器技术服务有限公司，建立了气相色谱法测定粮食水分的实验方法。采用超声波振荡提取粮食水分。色谱分析条件为:Porapak QS色谱柱,2 m×3 mm、80~100目;进样口温度140~150℃;热导池检测器温度100℃;氢气(99.999%)为载气,流速70μL/min。水含量在2.15~21.51 mg/mL与相应的色谱峰面积呈显著线性相关,相关系数R2=0.9993,检出限为1.8×10-4μg。分别以甲醇和无水乙醇为提取溶剂对同一样品进行5次测定,测定结果的标准偏差分别为0.17%和0.23%,变异系数分别为1.23%和1.70%。采用气相色谱法和105℃恒重法对样品进行测定,以甲醇为提取溶剂的测定结果与国标法测定结果的极差为1.1%,平均偏差为0.53%;以无水乙醇为提取溶剂的测定结果与国标法测定结果的极差为1.7%,平均偏差为0.36%。结果表明,气相色谱测定水分快速灵敏、成本较低,适合于大量样品的水分含量测定。

Determination of moisture in grain by gas chromatography
Determination of moisture in grain by gas chromatography


Name: Packed column
Specification: 2m*3mm
Model: Porapak QS
Application: Determination of moisture in grain by gas chromatography

Tengzhou Haohan Chromatography Instrument Technology Service Co., Ltd. established an experimental method for the determination of moisture in grain by gas chromatography. Use ultrasonic vibration to extract grain moisture. Chromatographic analysis conditions are: Porapak QS chromatographic column, 2 m×3 mm, 80~100 mesh; inlet temperature 140~150℃; thermal conductivity cell detector temperature 100℃; hydrogen (99.999%) as carrier gas, flow rate 70μL /min. The water content of 2.15~21.51 mg/mL has a significant linear correlation with the corresponding chromatographic peak area, the correlation coefficient R2=0.9993, and the detection limit is 1.8×10-4μg. Using methanol and absolute ethanol as extraction solvents, the same sample was tested 5 times. The standard deviations of the determination results were 0.17% and 0.23%, and the coefficient of variation was 1.23% and 1.70%. The samples were measured by gas chromatography and 105°C constant weight method. The measurement results with methanol as the extraction solvent had a range of 1.1% and an average absolute deviation of 0.53%. The range between the measurement result and the national standard method was 1.7%, and the average absolute deviation was 0.36%. The results show that the gas chromatography is fast, sensitive and low in cost, which is suitable for the determination of the moisture content of a large number of samples.