气相色谱法测定污水厌氧消化过程产生的挥发性脂肪酸  

Determination of Volatile Fatty Acids Produced in Anaerobic Digestion Process of Wastewater by Gas Chromatography

作　　者：刘只欣[1] 

机构地区：[1]北京城市排水集团有限责任公司水质检测中心,北京100124

出　　处：《中国给水排水》2014年第24期144-146,150,共4页China Water & Wastewater

摘　　要：建立了用毛细柱气相色谱法测定污水厌氧消化过程中产生的挥发性脂肪酸的方法，对样品前处理pH值、色谱柱程序升温条件进行了优化选择，筛选出最佳的测定条件，并对样品的重复性和加标回收率进行了考察。通过对比试验得出最佳测定条件，样品用磷酸调至pH=3，色谱柱条件为初始柱温为95℃，保持2min，然后以10℃／min的速率升温至140oC，再以40℃／min的速率升温至200℃，保持3min。在该优化条件下测定四种酸的相对标准偏差在4．2％～7．2％之间（n=7），方法检出限（MDL）为0．2～0．4mg／L，对实际污水样品加标回收率均在92．1％～108％范围内。实验证明，该方法分离度高，重复性好，测定时间短，具有良好的线性，能够快速、准确地测定污水厌氧消化过程中产生的挥发性脂肪酸含量。A method for determination of volatile fatty acids （VFAs） produced in anaerobic diges- tion process of wastewater by capillary colunm gas chromatography （ GC ） was established. The optimal determination conditions were selected through the investigation of the pH for sample pretreatment and temperature-programming condition of the GC column. The repeatability and recovery of the samples were studied. The optimal determination conditions were as follows, samples were acidified approximately to pH = 3 by phosphoric acid ; the initial GC column was 95℃, which was hold for 2 min ; the temperature rose to 140℃ at a rate of 10 ℃/min; and the temperature rose to 200℃ at a rate of 40℃/min and kept for 3 min. Under the optimized conditions, the relative standard deviations of the four kinds of acids were 4.2% to 7.2% （n =7）. The method detection levels （MDL） were 0.2 mg/L to 0.4 mg/L. The recovery rates of the actual wastewater samples were 92.1% to 108%. The results indicated that the method has high degree of separation, good repeatability, short testing time and good linearity, and it can determine the contents of volatile fatty acids produced in anaerobic digestion process of wastewater quickly and accurately.

关 键 词：挥发性脂肪酸 气相色谱法 毛细柱 

分 类 号：X832[环境科学与工程—环境工程]