Determination of 27 pharmaceuticals and personal care products (PPCPs) in water: The benefit of isotope dilution

• Isotope dilution method was developed for the determination of 27 PPCPs in water. • The established method was successfully applied to different types of water samples. • The correction effect of corresponding 27 ILSs over 70 d was investigated. • Benefit of isotopic dilution method was illustrated for three examples. Pharmaceuticals and personal care products (PPCPs) are a unique group of emerging and non-persistent contaminants. In this study, 27 PPCPs in various water samples were extracted by solid phase extraction (SPE), and determined by isotope dilution method using liquid chromatography coupled to tandem triple quadruple mass spectrometer (LC-MS/MS). A total of 27 isotopically labeled standards (ILSs) were applied to correct the concentration of PPCPs in spiked ultrapure water, drinking water, river, effluent and influent sewage. The corrected recoveries were 73%–122% with the relative standard deviation (RSD)<16%, except for acetaminophen. The matrix effect for all kinds of water samples was<22% and the method quantitation limits (MQLs) were 0.45–8.6 ng/L. The developed method was successfully applied on environmental water samples. The SPE extracts of spiked ultrapure water, drinking water, river and wastewater effluent were stored for 70 days, and the ILSs-corrected recoveries of 27 PPCPs were obtained to evaluate the correction ability of ILSs in the presence of variety interferences. The recoveries of 27 PPCPs over 70 days were within the scope of 72%–140% with the recovery variation<37% in all cases. The isotope dilution method seems to be of benefit when the extract has to be stored for long time before the instrument analysis.     

固相萃取-超高效液相色谱/三重四极杆质谱法同时测定地表水中8种亚硝胺类化合物

建立了固相萃取（SPE）-超高效液相色谱/三重四极杆串联质谱（UPLC-MS/MS）同时测定地表水中8种亚硝胺类化合物的方法。水样中目标物经椰壳活性炭固相萃取小柱吸附富集，小柱经氮气吹干后采用二氯甲烷洗脱。待测样品采用Atlantis T₃柱，以水-甲醇作为流动相进行梯度洗脱，大气压力化学电离源（APCI）正离子模式多反应监测方式（MRM）进行检测，内标法定量分析。8种目标物在相关线性范围内线性良好(r≥0.9950)，地表水加标回收率为55.4%~90.4%，相对标准偏差为3.1%~14.3%，方法检出限为1.1 ~1.8 ng/L。本方法准确度和灵敏度高，适用于快速测定地表水中8种亚硝胺类化合物含量。     

北京地区PM10与秸秆燃烧排放单颗粒对比分析

采用场发射带能谱扫描电镜(FESEM/EDS)法分析北京怀柔地区PM₁₀与秸秆燃烧排放颗粒的形貌特征和成分差异。结果显示:秸秆燃烧后排放颗粒物多为大粒径颗粒,成分上都含S、Cl和K元素。含有生物质燃烧标志元素K的PM₁₀颗粒物多为含Si、Al和Na元素的燃煤飞灰和矿物颗粒,与秸秆燃烧排放颗粒组成化学元素差异明显。据此推断,北京区域PM₁₀受秸秆燃烧排放影响相对较弱,化石燃料燃烧来源影响仍然显著。     

山东省主要河流中抗生素污染组成及空间分布特征

采用固相萃取-液相色谱/串联质谱法研究了山东省境内四大流域主要河流中抗生素污染组成及空间分布特征,涉及我国用量最大的6类共20种抗生素。结果表明:20种抗生素均有检出,且大环内酯类、喹诺酮类和四环素类抗生素整体检出浓度较高。就流域而言,半岛诸河流域抗生素污染较小,平均总质量浓度61.4 ng/L;海河流域、小清河流域和淮河流域相对较为严重,平均总质量浓度分别为232、175、118 ng/L。抗生素空间分布呈现一定的规律,检出浓度较高的点位主要集中在人口密集区下游,抗生素污染与周边生活污水、养殖企业废水和城市污水处理厂排水密切相关,而且抗生素组成可从一定程度上反映出污染来源。     

交通限行对大气颗粒物及PM2.5中二NFDA1英的影响

为了研究北京大气颗粒物和二NFDA1英(PCDD/Fs)的污染状况以及评估交通限行对大气颗粒物和PCDD/Fs的影响。利用同位素稀释高分辨率气相色谱/高分辨率质谱(HRGC/HRMS)联用法和USEPA 1613B 标准方法,以中国地质大学(北京)东门为采样点,采集大气PM_2.5、PM₁₀、TSP样品,对北京市交通限行期间以及交通限行前后等不同交通状况下颗粒物浓度及大气PM_2.5中17种2,3,7,8-PCDD/Fs污染特征进行了监测。结果表明,PM_2.5、PM₁₀、TSP的日均质量浓度在交通限行前分别为126、202、304 μg/m³,限行期间分别为39、78、93 μg/m³,限行结束后分别为79、126 μg/m³。PM_2.5中17种PCDD/Fs的质量浓度(毒性浓度)3个时段分别为1 804 fg/m³(70 fg I-TEQ/m³)、252 fg/m³ (9 fg I-TEQ/m³)和1 196 fg/m³ (48 fg I-TEQ/m³)。北京市交通限行期间颗粒物浓度和二 NFDA1 英浓度显著低于交通限行前后,交通源减排措施的实施是大气颗粒物和二 NFDA1英污染水平降低的主要原因,从减排效果看,交通源减排措施对大气细颗粒物(PM_2.5)的控制效果明显好于大气粗颗粒物。     

Enhanced triallyl isocyanurate (TAIC) degradation through application of an O3/UV process: Performance optimization and degradation pathways

• UV/O₃ process had higher TAIC mineralization rate than O₃ process. • Four possible degradation pathways were proposed during TAIC degradation. • pH impacted oxidation processes with pH of 9 achieving maximum efficiency. • CO₃^2– negatively impacted TAIC degradation while HCO₃^– not. • Cl^– can be radicals scavenger only at high concentration (over 500 mg/L Cl^–). Triallyl isocyanurate (TAIC, C₁₂H₁₅N₃O₃) has featured in wastewater treatment as a refractory organic compound due to the significant production capability and negative environmental impact. TAIC degradation was enhanced when an ozone(O₃)/ultraviolet(UV) process was applied compared with the application of an independent O₃ process. Although 99% of TAIC could be degraded in 5 min during both processes, the O₃/UV process had a 70%mineralization rate that was much higher than that of the independent O₃ process (9%) in 30 min. Four possible degradation pathways were proposed based on the organic compounds of intermediate products identified during TAIC degradation through the application of independent O₃ and O₃/UV processes. pH impacted both the direct and indirect oxidation processes. Acidic and alkaline conditions preferred direct and indirect reactions respectively, with a pH of 9 achieving maximum Total Organic Carbon (TOC) removal. Both CO₃^2– and HCO₃^– decreased TOC removal, however only CO₃^2– negatively impacted TAIC degradation. Effects of Cl^– as a radical scavenger became more marked only at high concentrations (over 500 mg/L Cl^–). Particulate and suspended matter could hinder the transmission of ultraviolet light and reduce the production of HO· accordingly.     

MoS_2/Bi_2S_3异质结光催化剂的制备及其光催化性能

以五水硝酸铋为铋源、钼酸钠为钼源、硫脲为硫源,采用简单的一步水热法合成了MoS_2/Bi_2S_3异质结光催化剂,采用XRD,SEM,TEM,BET,UV-Vis DRS技术对其进行了表征。表征结果显示,MoS_2纳米片在Bi_2S_3微棒表面生长,增加了比表面积和活性位点,并形成异质结构,促进了光生载流子的迁移,抑制了电子-空穴对的再复合。实验结果表明:钼酸钠与五水硝酸铋的质量比为1∶2时制备的复合光催化剂性能最好,反应180min时对亚甲基蓝的去除率可达96.4%,明显高于MoS_2和Bi_2S_3,且具有较高的稳定性;该催化剂对罗丹明B、甲基橙和4-硝基苯酚的去除率分别为97.1%、93.1%和90.5%,表明其对污染物具有普适性。     

武汉市秋季PM2.5中硫酸盐、硝酸盐理化特征及影响因素

为了解武汉市秋季PM_(2.5)中硫酸盐、硝酸盐理化特征,2016年9—11月利用热还原法在线连续监测分析系统对此进行了采样分析,并同步收集气象因子和离子色谱方法监测结果。结果表明,硫酸盐、硝酸盐的热还原分析方法与离子色谱法的相关系数分别为0.88、0.94;PM_(2.5)中硫酸盐、硝酸盐的水溶性部分占比达92.5%,难溶性部分为7.5%;空气质量为优、良和轻度污染时,硫酸盐、硝酸盐与PM_(2.5)的占比分别为45%、42%、45%;硫酸盐、硝酸盐在降水日和非降水日平均质量浓度分别为(19.6±18.5)μg/m~3和(31.0±9.1)μg/m~3;硝酸盐与硫酸盐的质量比为1.1,高于国内其他城市,与武汉市机动车保有量大幅增加有关。     

加速溶剂萃取-固相萃取/超高效液相色谱-串联质谱法测定沉积物中5种微囊藻毒素

建立了加速溶剂萃取-固相萃取/超高效液相色谱-串联质谱法同时测定沉积物中5种微囊藻毒素(MC-LR、MC-RR、MC-LW、MC-LF、MC-YR)的方法。选择甲醇-水(1∶4,V/V)为ASE萃取溶剂,萃取温度和萃取压力分别为80℃和13.1 MPa,固相萃取过程以HLB小柱为萃取柱,采用液相色谱-串联质谱分析。方法在5种微囊藻毒素质量浓度5~100μg/L内线性良好(r0.995),回收率为76.0%~118%,相对标准偏差为1.9%~12.0%,检出限为2~3μg/kg,定量下限为8~12μg/kg。该方法已用于西太湖沉积物的检测,具有较好的方法适用性。     

300MW燃煤锅炉机组超细颗粒聚并器的实验研究

为了解决燃煤锅炉烟气中超细颗粒难以脱除的问题,基于流体动力学原理设计了一种超细颗粒聚并器,并在300 MW燃煤锅炉机组电除尘器的前置烟道中进行了实验研究。结果表明,聚并器内部存在超细颗粒之间以及超细颗粒与大颗粒之间的相互聚集行为,从而使超细颗粒数量显著减少。例如,对于粒径在2.65和10.48μm以下的颗粒,其体积比例在聚并器出口分别减少了56.7%和62.3%,在电除尘器出口的粉尘浓度减少了26.34 mg/Nm3,这表明,基于流体动力学原理的聚并器对超细颗粒的聚并作用明显,具有良好的应用前景。