超声提取-高温燃烧吸收-离子色谱法测定纺织品中可吸附有机卤化物北大核心CSCD

建立了一种对纺织品中可吸附有机卤化物(AOX)的超声提取-高温燃烧吸收-离子色谱定量检测分析新方法。该方法采用超声方式提取纺织品中的AOX,提取液加入活性炭进行振荡吸附,并用酸性硝酸钠溶液对无机卤化物进行去除。采用程序升温的氧化燃烧方式对吸附AOX的活性炭进行裂解、燃烧及气化,其产生的卤化氢等气体随载气进入吸收液并完全转化为无机卤素阴离子,采用离子色谱分离测定,外标法定量。实验优化了超声提取时间、活性炭用量、燃烧气及其流量、燃烧升温程序、吸收液和吸收方式等前处理条件,并对离子色谱的仪器分析条件如色谱柱、柱温及淋洗液流速等进行优化。结果表明,氟、氯、溴、碘4种卤素离子的标准溶液在0.02~10 mg/L范围内呈线性关系,线性相关系数(R^(2))均在0.999以上;AOX测定的方法定量限为0.10~0.50 mg/kg。以棉、毛和涤纶3种不同种类的阴性纺织样品作为样品基质,选取典型的有机卤化物进行加标,在低、中、高3个加标水平下测得AOX的平均回收率为82.3%~98.7%,相对标准偏差(RSD,n=7)为2.0%~5.7%,表明方法具有良好的回收率和精密度。将该方法应用于实际纺织样品的测定,检出了不同含量的AOX,且重复性好。研究建立的方法通过采用活性炭的振荡吸附、程序升温的高温氧化燃烧方式和多孔吸收瓶的二级吸收方法,提高了AOX转化为无机卤素的回收率;同时利用离子色谱仪器选择性好、灵敏度高的特点成功地一次性分离检测4种AOX,且无杂质离子的干扰。该方法简单、准确、可靠,满足国内外法规和标准对纺织品中AOX的限量要求,适用于纺织品中AOX的分析测定。

Determination of adsorbable organic halogens in textiles by ultrasonic extraction-high temperature combustion absorption-ion chromatography

Adsorbable organic halogens(AOX)are often introduced or produced in textile and dyeing processes,such as the chlorination shrink proof process of wool,the bleaching process by sodium hypochlorite and chlorite,the dry-cleaning process by chlorinated solvent,etc.However,part of AOX is difficult to biodegrade and is a persistent bioaccumulative toxic substance with high fat solubility.To promote clean production of textiles and to protect the health of consumers,a conventional method for the detection of AOX in textiles must be established urgently.In this study,a new method was developed for the determination of AOX in textiles by ultrasonic extraction-high temperature combustion absorption-ion chromatography(IC).In this method,AOX in textiles were extracted by ultrasonic extraction at room temperature with ultra-pure water as solvent.Activated carbon was added to the extraction solution for oscillatory adsorption and removal of inorganic halides with acidic sodium nitrate solution.The AOX adsorbed on activated carbon were cracked,burned,and gasified by the oxidative combustion method with a programmed heating mode.The product hydrogen halide gas entered the absorption solution with the carrier gas,followed by separation and determination by IC with external standard method of quantification.During the experiment,the pretreatment conditions were optimized,including the extraction time of AOX,the amount of activated carbon,the combustion gas and its flow rate,the temperature program for high-temperature oxidation combustion,the absorption method,and the absorption solution.The instrument conditions of ion chromatography,including the chromatographic column,column temperature,eluent,and its flow rate,were also optimized.The results showed that the method was linear in the range of 0.02-10 mg/L for the standard solutions of fluorine,chlorine,bromine,and iodine ions,and the correlation coefficients(R²)were greater than 0.999.The limits of quantification of the method for AOX were 0.10-0.50 mg/kg.The negative textile samples of cotton,wool,and polyester were used as the sample matrix,and typical organic halogens were selected for standard addition and recovery.At low,medium,and high spiked levels,the average recoveries of AOX in cotton,wool,and polyester fiber were 82.3%-98.7%.The corresponding relative standard deviations(RSDs,n=7)were 2.0%-5.7%,indicating that the method had good recovery and precision.This method was used to determine actual textile samples,and AOX at different contents were detected in blue coated polyester fabric and black modal fabric with good repeatability.The established method improved the recoveries of AOX converted into inorganic halogens via oscillating adsorption of activated carbon,high-temperature oxidation combustion with a programmed heating mode,and secondary absorption using a porous absorption bottle.Meanwhile,the separation and detection of halogen ions was successfully conducted using the ion chromatography instrument with good selectivity and high sensitivity,without any interference of impurity ions.The method is simple,accurate,and reliable,and fully meets the limit requirements of domestic and foreign regulations and textile standards;the method is also suitable for the detection and analysis of AOX in textiles.