纳氏试剂两种配制方法对氨氮测定的影响比较

对纳氏试剂的两种配制方法在配制难易和含汞量、空白吸光度、校准曲线、检出限、精密度和加标回收率等方面作了比较,得出KI、HgCl2和KOH配制的纳氏试剂与KI、HgI2和NaOH配制的纳氏试剂相比,配制虽麻烦,但含汞量、空白吸光度和检出限均较低,而灵敏度、精密度和加标回收率却较高,可作为配制纳氏试剂的首选方法。而KI、HgI2和NaOH配制的纳氏试剂可用于应急监测中。     

磁强化Fenton试剂降解表面活性剂污水的实验研究

研究不同磁化时间、不同磁场强度以及催化氧化体系中各种影响因素对表面活性剂污水CODcr的去除率的影响。结果表明:在pH值3,H2O2加入量为0.5%(体积比),FeSO4.7H2O浓度为3 000 mg/L,反应10min,去除率达69.8%。在相同实验条件下,外加磁场强度分别为235.6 mT、357.3 mT、427.8 mT,CODcr的去除率可提高3.5%、8.4%、10.5%。     

Fenton treatment of olive oil mill wastewater--applicability of the method and parameters effects on the degradation process

The low biodegradability of polyphenolic compounds typically found in olive processing indicated that biological treatment is not always successful in the treatment of olive oil mill wastewater in term of COD removal. In this study the results of investigations on the applicability of Fenton‘s reagent in the treatment of this effluent were discussed. The efficiency of this method was determined. 86% of removal COD was obtained using 5 mol H2O2 and 0.4 mol Fe^2 per liter of crude OMW. The main parameters that govem the complex reactive system, i.e., time, pH, [H2O2] and [Fe(ll)] were studied.     

Fenton试剂-超声波降解硝基苯产物的分析

用Fenton试剂—超声波振荡法对硝基苯水溶液进行降解处理,采用气相色谱-质谱联用法分析降解的中间产物,用离子色谱法分析降解的最终产物。实验结果表明：硝基苯降解中间产物中含有间二硝基苯,邻、间、对硝基苯酚及苯酚;降解的最终产物主要为硝酸根,本文同时研究了中间产物在降解过程中浓度的变化规律。     

固体试剂快速测定水中阴离子表面活性剂

对亚甲蓝分光光度法进行改进,用固体试剂快速测定水中的阴离子表面活性剂。在最大吸收波长652nm处,阴离子表面活性剂质量浓度为0~2.0m g/L时遵守比尔定律,表观摩尔吸光系数为1.56×104L/(m o.lcm),检出限为0.03m g/L。该方法用于自来水、河水和工业废水中阴离子表面活性剂的测定,取得了满意结果。环境水样的平均回收率为88.3%~108.0%,相对标准偏差不超过4.67%。     

Fenton试剂预处理高浓度丁腈胶乳生产废水

采用Fenton试剂预处理高浓度丁腈胶乳生产废水,确定最佳操作条件为:[H2O2]= 2 664 mg/L,[Fe2 ]=219 mg/L,初始pH=5.0,25 ℃下反应60 min,此条件下废水COD去除率可达80%以上.经正交试验得出各因素对废水COD去除率的影响顺序为:pH＞[H2O2]＞[Fe2 ]＞反应时间.动力学研究表明,在此最佳操作条件下,反应近似符合一级反应动力学,动力学方程ln(C0/C)=0.018 7t 0.783 1,反应速率常数k=0.018 7 min-1,半衰期t 1/2=37.1 min.     

酸析-Fenton试剂氧化-混凝法处理制浆废水

用酸析-Fenton试剂氧化-混凝法对自偶氧化清洁制浆废水进行预处理,考察了各种因素对处理效果的影响。最佳处理条件：酸析时的废水pH为3．0;酸析后上层清液无需调节pH,加水稀释至COD为2000mg／L后进行Fenton试剂氧化,H2O2加入量为84．56mmol／L,FeS04加入量为8．44mmol／L,反应时间60min;混凝时Ca（OH）：加入量为2g／L。最终出水的COD为577．20mg／L（COD去除率为71．14％）,色度为36倍,pH为8．60。     

水泥回转窑处理废弃化学试剂的实验

实验室或生产中产生的废弃化学试剂是一类危险废物,必须进行特殊处理,用水泥回转窑处置是一种值得推广的方法。通过将实验室常用的8类化学试剂在回转窑实验,表明水泥掺加化学试剂后,水泥熟料xrd图谱相似,主要矿物相没有发生改变;对水泥的7、28d抗压强度的影响较小,熟料试样在其水化28d时各重金属的浸出量都很低,符合国家标准。因此利用水泥回转窑处理废弃化学试剂方法可行,对环境不具危害作用。     

Chemical oxidation of cable insulating oil contaminated soil

Leaking cable insulating oil is a common source of soil contamination of high-voltage underground electricity cables in many European countries. In situ remediation of these contaminations is very difficult, due to the nature of the contamination and the high concentrations present. Chemical oxidation leads to partial removal of highly contaminated soil, therefore chemical oxidation was investigated and optimized aiming at a subsequent bioremediation treatment. Chemical oxidation of cable oil was studied with liquid H₂O₂ and solid CaO₂ as well as permanganate at pH 1.8, 3.0 and 7.5. Liquid H₂O₂ most effectively removed cable oil at pH 7.5 (24%). At pH 7.5 poor oil removal of below 5% was observed with solid CaO₂ and permanganate within 2 d contact time, whereas 18% and 29% was removed at pH 1.8, respectively. A prolonged contact time of 7 d showed an increased oil removal for permanganate to 19%, such improvement was not observed for CaO₂.Liquid H₂O₂ treatment at pH 7.5 was most effective with a low acid use and was best fit to a subsequent bioremediation treatment. To further optimize in situ chemical oxidation with subsequent bioremediation the effect of the addition of the iron catalyst and a stepwise liquid H₂O₂ addition was performed. Optimization led to a maximum of 46% cable oil removal with 1469 mM of H₂O₂, and 6.98 mM Fe(II) chelated with citric acid (H₂O₂:FeSO₄ = 210:1 (mol mol⁻¹). The optimum delivery method was a one step addition of the iron catalyst followed by step wise addition of H₂O₂.     

类Fenton试剂氧化降解土壤中PAHs及其影响因素研究

使用类Fenton试剂可以有效降解土壤中的多环芳烃（PAHs）。选择4种PAHs菲、芘、苯并[a]芘、茚并（1,2,3-cd）芘作为考察对象,研究了类Fenton试剂对土壤中PAHs的降解条件。单因素降解实验结果表明,在H2O2浓度为0.5mol/L,Fe（NO3）3浓度为0.1 mol/L,水土比为3∶1,反应时间为...