Extraction equipment chlorophenol in waste water using liquid chromatography test
Chlorine phenolics as widely used as a wood preservative, anti-rust agent, fungicide and pesticide, etc. , and therefore is widely distributed in the environment;
Recently in waste, sludge, sediment, soil, groundwater, surface water and rain water have been detected in the chlorine phenolics.
2, 4-2 chlorophenol (
, 2 minus 2 - trichlorophenol (
, pentachlorophenol (
Pollution of chlorophenol compounds such as high toxicity, side wide, has been included in the list of priority control of water pollutants in China.
The surface water environment quality standards and a of integrated wastewater discharge standard will be chlorine phenolic substances listed in the control range.
The current GB 8978 -
chlorine phenolics monitoring methods mainly have spirit chromatography and liquid-solid extraction - liquid chromatography (HPLC).
Gas chromatography determination of chlorophenol generally need derivative, process complex, and liquid-solid extraction - performance liquid chromatography (HPLC) method for sample preparation equipment demand is higher, invest more.
This study established the liquid-liquid extraction, liquid chromatography (HPLC) analysis method for determination of the three kinds of material at the same time, meet the requirement of chlorophenol in waste water monitoring, and the method is simple and accurate, and has good practical application value.
Water environment of chlorophenol generally exists in the form of its conjugate base, by adjusting the pH � � 2 ~ 3, make component exists in the form of chlorophenol, with dichloromethane extraction;
5 mol/L K2CO3 reverse extraction, transformation of chlorophenol to chlorophenol salt into alkaline solution, measurement with liquid chromatography with uv detector.
Through the multi-stage extraction and reverse extraction, enrichment of components, and to improve the detection limit of the method,
Use of extraction and reverse extraction, can make the part of the interference of organic matter is removed, to improve the selectivity of the method.
to liquid-liquid extraction system in a certain amount of inorganic salt can reduce the water molecule activity, reduce the extraction material combined with the water ability, thus improve the extraction efficiency.
NaCl dosing quantity and the influence of chlorophenol recovery relations are shown in table 3.
Can be seen from table 3, NaCl dosing significantly improved the extraction efficiency of three kinds of chlorophenol.
When NaCl dosing quantity increased to more than 10 g, the recovery rate of the three kinds of chlorophenol leveled off, therefore, determine the optimal dosing quantity of NaCl for 10 g.
At the same time, the water samples by acidification and add NaCl treatment of sulfuric acid and methylene chloride in 2 times extraction has reduced the emulsifying phenomenon, then emulsified part transferred to clean the separatory funnel of decompression stirring with a glass rod.
the liquid-liquid extraction - HPLC method to detect chlorophenol in wastewater, the less sample preparation equipment, simple operation.
Mu 7 g/L, is suitable for wastewater in DCP, TCP, PCP detection analysis.