氣相色譜法測定糧食中的水分，液化石油氣，二甲醚，甲縮醛，乙縮醛，乙醇，室內(nèi)空氣，焦爐煤氣，煉廠氣，天然氣，變壓器油，多氯聯(lián)苯，植物油，6號溶劑殘留，裂解進樣器，消毒劑

氣相色譜法測定糧食中的水分
氣相色譜法測定糧食中的水分 詳細信息：


名稱：填充柱
規(guī)格：2m*3mm
型號：Porapak QS
應(yīng)用： 氣相色譜法測定糧食中的水分

滕州市浩瀚色譜儀器技術(shù)服務(wù)有限公司，建立了氣相色譜法測定糧食水分的實驗方法。采用超聲波振蕩提取糧食水分。色譜分析條件為:Porapak QS色譜柱,2 m×3 mm、80~100目;進樣口溫度140~150℃;熱導(dǎo)池檢測器溫度100℃;氫氣(99.999%)為載氣,流速70μL/min。水含量在2.15~21.51 mg/mL與相應(yīng)的色譜峰面積呈顯著線性相關(guān),相關(guān)系數(shù)R2=0.9993,檢出限為1.8×10-4μg。分別以甲醇和無水乙醇為提取溶劑對同一樣品進行5次測定,測定結(jié)果的標準偏差分別為0.17%和0.23%,變異系數(shù)分別為1.23%和1.70%。采用氣相色譜法和105℃恒重法對樣品進行測定,以甲醇為提取溶劑的測定結(jié)果與國標法測定結(jié)果的極差為1.1%,平均偏差為0.53%;以無水乙醇為提取溶劑的測定結(jié)果與國標法測定結(jié)果的極差為1.7%,平均偏差為0.36%。結(jié)果表明,氣相色譜測定水分快速靈敏、成本較低,適合于大量樣品的水分含量測定。

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.