Cloud Point Extraction For Determination Of Hg,Pb And Phenol In Environmental Water Samples

Mercury,lead and phenol are highly toxic pollutants widely distributed in the environment,which pose a huge threat to human health and ecological environment.Quantitative analysis is an important part of environmental monitoring in various countries.Due to the complex matrix of the environment water and the low content of the analytes,the samples need to be separated and enriched to improve the accuracy and sensitivity of the detection.Cloud point extraction is a kind of preconcentration and separation technology with high environmental friendliness,simple operation,high resolution and enrichment factor.This paper systematically studied the technology of cloud point extraction in the separation and enrichment of mercury,lead and phenol,established a new method for the separation and enrichment of mercury,lead and phenol in the environment,and combined these methods with a variety of detection techniques,successfully applied to the analysis of mercury,lead and phenol in environmental water samples with satisfactory results.This article includes the following five parts:1.The current situation and harm of mercury,lead and phenol on water environment pollution and the significance and common methods of quantitative monitoring of mercury,lead and phenol in water environment were comprehensively investigated and analyzed.The principle of cloud point extraction technology was expounded.The influencing factors were deeply analyzed.The application of cloud point extraction in the determination of trace heavy metals and phenol in the environment was comprehensively reviewed.2.A new method for the speciation analysis of inorganic mercury and methyl mercury by dual-cloud point extraction-liquid chromatography-hydride generation atomic fluorescence spectrometry was established.Dual-cloud point extraction as a means of separation and enrichment for the first time combined with liquid chromatography hydride generation-atomic fluorescence spectrometry to achieve the determination of inorganic mercury and methyl mercury in water samples.The HPLC conditions were reversed-phase C18 column,5%acetonitrile mobile phase containing 60 mM ammonium acetate and 10 mM cysteine.The effects of factors such as extraction pH,reagent concentration on cloud point extraction were discussed.Under the optimized conditions,mercury and methyl mercury in 10mL sample solution have a good linear relationship with absorbance in the concentration range of 0.5¹0?g/L.The linear equation of Hg???is y=106775x-2170.9,R²=0.9986,the enrichment factor is 7.39.The linear equation of MeHg is y=35530x+1380.5,R²=0.9992.The detection limits of mercury and methyl mercury were 0.025?g/L and 0.042?g/L,the enrichment factors 7.39 and 4.25,the spiked recoveries of Hg???and MeHg were between 99.7%¹04.6%and 96.5%⁹8.3%,respectively.3.A new method of co-extraction assisted cloud point extraction-graphite furnace atomic absorption spectrometry for the determination of lead in water samples was established.For the first time alizarin yellow R as a complexing agent,by adding CaCl₂ to establish a co-extraction system,the Pb into a hydrophobic complex,which was extracted to Triton X-114 surfactant phase,separated by centrifugation and water,and finally dilute with a 1%nitric acid methanol solution to reduce the surfactant viscosity and determine by graphite furnace atomic absorption spectrometry.Under the optimal experimental conditions,the Pb concentration was in the range of 0.40-4.8?g/L,which was in good linear relationship with the absorbance.The standard curve equation A=0.1122c+0.0045,the correlation coefficient R²=0.9959,the detection limit was 0.0289?g/L.The method was successfully applied to the determination of trace Pb in water samples with recoveries of 98.0%¹03.6%.4.The establishment of a rapid synergetic cloud point extraction-fluorescence spectrophotometry for the determination of phenol in the environmental water a new method.Non-toxic non-ionic surfactant polyethylene glycol 6000 as extractant,n-octanol as cloud point induction synergist,together with anhydrous sodium sulfate polyethylene glycol 6000cloud point temperature dropped to about 20?,The extraction can be completed without heating,and the factors affecting the extraction rate of phenol are experimentally optimized.For the 50mL sample solution,under the optimal conditions,the phenol concentration in the range of 0.02¹.60?g/mL linear well,the standard curve equation F=5675.6c-2.0598,the correlation coefficient R²=0.9998.The detection limit was 0.0027?g/mL,the extraction rate of phenol reached 89.8%,the enrichment factor was 8.33 and the spiked recoveries ranged from 90%to 110%.The method is simple,rapid,time-saving,high sensitivity and wide linear range,and is suitable for the determination of phenol in environmental water samples.5.Summarize the innovation of the method established in this paper,and forecasted the innovation of cloud point extraction technology and its application in more fields.