超临界态二氧化碳再生活性炭法治理甲苯废气

制鞋业产生的含甲苯、苯和二甲苯废气的治理大多采用活性炭吸附法。该课题提出以压缩二氧化碳为脱附剂,采用超临界流体萃取技术再生活性炭及回收甲苯工艺。实验表明,以液态或超临界态的压缩二氧化碳作萃取剂,采用萃取法可完全再生活性炭,其采用液态优于超临界态;压缩二氧化碳对活性炭具有扩孔作用,可增加活性炭的吸附容量,多次再生的活性炭吸附容量几乎不变;萃取剂的用量和密度显著影响着活性炭的再生效率;活性炭捆包填充在脱附塔中,不会显著增加脱附的阻力。      

Application and mechanism of polysaccharide extracted from Enteromorpha to remove nano-ZnO and humic acid in coagulation process

Green source Ep was extracted from marine alga waste. The molecule model structure of Ep was studied and constructed. PAC-Ep coagulation system improves the efficiency of removal efficiency. Synergistic effects between NPs and HA make a big difference to enhance efficiency. Mechanism is charge neutralization, hydrogen bonding and adsorbing-complexing Enteromorpha polysaccharide (Ep) extracted from alga a novel green coagulant aid for nanoparticles (NPs) and heavy metal ions removal and the structure of EP was intensively studied in this study. The integration of Ep with polyaluminum chloride (PAC-Ep) coagulants exhibited higher coagulation performance than that of the polyaluminum chloride (PAC) because of the negatively charged NPs suspension and humic aid (HA) solution. Significant high removal efficiencies of dissolved organic matter (94.1%), turbidity (99.3%) and Zn ions (69.3%) were achieved by the PAC-Ep coagulants. The dual-coagulation properties of PAC-Ep for different pollutants was based on multiple mechanisms, including (i) Al³⁺ charge neutralization; (ii) hydroxy aluminum hydroxyl bridging formed polynuclearhydroxy complexes bridge and sweep colloidal particles; (iii) adsorption and bridging of Ep chain for the NPs and heavy metal ions. Results indicated that the destabilization of colloid was induced by the coexisting HA and higher removal was achieved as ions adsorption was enhance in the presence of HA complexation. On the basis of that, the extraction of polysaccharide is a promising candidate for its high coagulation performance in water treatment.     

氯仿萃取法处理4-氨基安替比林的研究

用氯仿萃取法处理4-氨基安替比林可获得较低的空白测定消光值,并且步骤简便,易于操作。     

萃取法由废催化剂制取钼酸铵

用季胺盐作萃取剂，采用一级萃取回收废催化剂中的钼，其钼回收率可达９０％，反萃液可直接得到四钼酸铵，工艺简单，操作方便，具有显著的经济效益和一定的环境效益。     

萃取法预处理间二硝基苯生产废水

间二硝基苯生产废水中含有邻硝基苯磺酸和对硝基横酸，采用三辛胺－煤油作萃取剂对其进行萃取处理，在最佳工艺条件下，经过三级萃取，废水的COD去除率达95％以上，硝基物去除率达98％以上，萃取剂用NaOH水溶液处理后可循环使用。     

Extraction of arsenic in a synthetic arsenic-contaminated soil using phosphate

An environment-friendly and cost-effective extraction method has been studied for the removal of arsenic from contaminated soil. A yellow-brown forest soil was contaminated with arsenic(V) and used as a model soil. Among various potassium and sodium salts, potassium phosphate was most effective in extracting arsenic, attaining more than 40% extraction in the pH range of 6–8 with minimum damage to the soil properties. Exchange mechanism is proposed for the extraction of arsenic from soil by phosphate. Sequential extraction shows that phosphate is effective in extracting arsenic of Al- and Fe-bound forms. Arsenic of residual form was not extracted. Arsenic was efficiently extracted by phosphate solution of pH 6.0 at 300 mM phosphate concentration and at 40°C.     

从含油污泥中回收原油

介绍了含油污泥的来源、处理方法以及经济效益和环境效益。     

分散固相萃取/高效液相色谱法测定土霉素菌渣中土霉素的残留量

文章拟建立一种从土霉素菌渣中提取并检测土霉素残留量的高效液相色谱法。用甲醇和冰乙酸作为提取剂提取样品,用分散固相萃取的方法净化样品,净化药剂为石墨化碳黑(GCB)和C18。通过加标回收实验,用高效液相色谱仪检测样品中土霉素含量。选用的色谱柱为PLRP-S,流动相为甲醇和0.05 mol/L草酸,两者比例为35:65(V:V)。检测波长为355 nm,柱温30℃。经检测,土霉素在0.1~2 000 mg/L范围内线性相关系数大于0.999,线性良好。1.0,4.0及8.0mg/g 3个加标水平的土霉素平均回收率范围是80.85%~109.59%,相对标准偏差(RSD)为2.45%~6.38%。土霉素菌渣中土霉素残留量平均为4.741 mg/g。实验表明,该方法具有简单、方便、快速、准确性强、灵敏度高的特点,可以应用于土霉素的分析检测。     

磁性固相萃取在环境分析中的应用

样品前处理直接影响污染物分析的准确性并很大程度上决定了目标物质的检测限。磁性固相萃取作为一种新兴的样品前处理技术,具有操作简单、消耗时间短、成本低等优点,克服了传统柱式固相萃取的缺陷,广泛应用于环境、化学、生物、药物分析等领域。文章介绍了磁性固相萃取技术及其流程,概述了各种磁性材料在痕量污染物富集分离过程中的应用现状,分析比较了不同表面修饰物质的磁性粒子的优缺点,并展望了磁性固相萃取未来的研究方向。     

固相萃取—气相色谱法测定海水中的666、DDT

采用固相萃取技术富集海水中的666、DDT,并使用气相色谱进行测定。主要包括不同填料(C8、C18、C18-N)、SPE柱规格(500 mg/3 mL、500 mg/6 mL)、洗脱试剂、上样流速、水样pH和洗脱试剂体积6个因素对666、DDT富集效率的影响。最终确定最优条件为:采用500 mg/6 mL C18SPE小柱,调节海水pH=6,上样流速4~5mL/min,10 mL二氯甲烷洗脱。优化后的固相萃取-气相色谱方法测定海水中666、DDT加标10 ng/L回收率为75.7%~110.4%,精密度为1.16%~4.00%,方法检出限为0.19~1.20 ng/L。