伏安法测定水中β-萘酚

研究了β-萘酚在多壁碳纳米管(MWNT)修饰电极上的电化学行为,在C6H8O7-Na2HPO4溶液中,β-萘酚在修饰电极上产生一对可逆峰,还原峰电位为-0.103V,氧化峰电位为-0.076V,该峰较灵敏、稳定,适于伏安测定。据此提出了一种灵敏,简便的检测β-萘酚的电化学分析方法。在合适的条件下,β-萘酚浓度在2×10-5～4×10-4mol/L范围内浓度与峰电流呈线性相关,相关系数r=0.9940,检出限2.5×10-7mol/L。同时对模拟水样进行测定,结果满意。     

UASB处理高浓度硫酸盐废水启动过程污泥特性变化

跟踪比较一套处理高浓度硫酸盐污水的UASB反应器从启动驯化到稳定运行的243 d内污泥特性的变化.结果显示颗粒污泥的形成与生物活性直接影响反应器的处理效率.反应器启动初期颗粒污泥的平均粒径由种泥的1.82 mm减少至0.99 mm;随着负荷增加、水力停留时间缩短,颗粒污泥平均粒径呈逐步增长趋势.采用N2吹脱反应器内产生的H_2S,N_2流量为60 mL·min~(-1)时,颗粒污泥的平均粒径快速增长至1.51 mm;N_2流量为100 mL·min~(-1)时,颗粒污泥平均粒径呈现下降趋势;N_2连续吹脱使得反应器内不同高度污泥的平均粒径趋于接近.污泥中活性微生物的量(MLVSS)在启动初期先降后升,升至33.59 g·L~(-1)之后平稳增长到49.72 g·L~(-1),活性污泥中微生物所占悬浮固体量的比例(MLVSS/MLSS)也呈相同的变化趋势,先下降后升至0.36之后平稳升至0. 50;相关性分析表明,反应器硫酸盐还原效率与MLVSS呈显著正相关(r=0.918,p=0.003),驯化过程中SO_4~(2-)还原效率为30%～95%.电镜分析表明,接种时颗粒污泥表面粗糙,结构松散,多为丝状菌、杆菌、球菌;驯化后颗粒污泥表面光滑内部微生物结构紧密,菌群密集,多为弧菌、杆菌.硫酸盐还原反应器驯化过程中负荷、水力停留时间、反应器内水力上升流速、以及N2吹脱强度和时间都影响颗粒污泥粒径的变化;污泥中菌群组成的变化也可能是影响颗粒污泥粒径变化因素之一.     

采用蒸气吹脱解附法对废弃活性炭回收醋酸丁酯的试验研究

试验用废弃活性炭做回收醋酸丁酯的研究,采用蒸气吹脱解附法,设计制作活性炭解吸塔,考察蒸气用量对活性炭解吸的影响,同时确定最佳解吸时间及可回收的丁酯量,并探讨回收醋酸丁酯的同时能够再生活性炭的试验条件。     

利用渗滤液中氨尾气进行烟气脱硝的可行性研究

通过分析垃圾焚烧厂SNCR烟气脱硝技术并结合渗滤液处理过程中的氨尾气处理,研究了焚烧厂采用渗滤液中氨尾气进行脱硝的可行性。研究表明,对于一座1 000 t/d中等规模垃圾焚烧厂来说,其渗滤液采用氨吹脱工艺不仅能节约生化脱氮成本,更能为烟气脱硝提供充足的还原剂氨,技术可行,为我国在"十二五"期间开展的氮氧化物减排治理工作提供参考。     

吹脱-Fenton氧化-沉淀工艺处理乙基氯化物废水

乙基氯化物是重要的农药中间体,广泛用于生产高效低毒有机磷农药,在生产过程中产生大量高COD、高磷、高硫等污染物的有毒废水。文章针对该废水的水质,提出了一种新的预处理工艺:吹脱-Fenton氧化-沉淀反应。试验结果表明:当吹脱时间为20 min,pH为3.10,Fenton反应双氧水与亚铁离子摩尔比为4:1,双氧水投加量为5 mL/L以及沉淀反应石灰投加量为14.5 g/L时,废水中的COD从228 g/L降低到56.60 g/L,硫离子浓度从88.94 g/L降低到12.26 g/L,总磷含量从10.37 g/L降低到0.98 g/L。     

RECIRCULATING WELLS: GROUND WATER REMEDIATION AND PROTECTION OF SURFACE WATER RESOURCES1

ABSTRACT: Several chlorinated solvent plumes threaten the sole‐source aquifer underlying the Massachusetts Military Reservation at the western end of Cape Cod. Sensitive surface water features including ponds, cranberry bogs, and coastal wetlands are hydraulically connected to the aquifer. For one of the plumes (CS‐10 the original remedy of 120 extraction and reinjection wells has the potential for significant disruption of surface water hydrology, through the localized drawdown and mounding of the water table. Recirculating wells with in‐well air stripping offer a cost‐effective alternative to conventional pump‐and‐treat technology that does not adversely affect the configuration of the water table. Pilot testing of a two well system, pumping 300 gpm, showed a capture radius of > 200 feet per well, in‐well trichloroethylene (TCE) removal efficiencies of 92 to 98 percent per recirculation cycle, an average of three recirculation cycles within the capture zone, and no measurable effect on water table elevations at any point within the recirculation/treatment zone. During 120 days of operation, the mean concentration of TCE in the treatment zone was reduced by 83 percent, from 1,111 μg/l to 184 μg/l. Full‐scale design projections indicate that 60 wells at an average spacing of 160 feet, having an aggregate recirculation 11 MGD, can contain the CS‐b plume without ground water extraction or adverse hydraulic effects on surface water resources. The estimated capital costs for such a system are about $7 million, and annual operations‐and‐maintenance costs should be about $1.4 million, 40 percent of those associated with a pump and treat system over a 20‐year period.     

吹脱技术净化石油污染地下水实验

利用现场动态实验对影响吹脱塔除污染的因素进行了实验研究 ,确定最佳气水比为 5∶1、淋水密度为 10.0 m³/( m²·h) ;在最佳运行状况下 ,吹脱法对地下水中油类物质的去除率可达 50%左右 ,还能去除水中的 NH₃-N、高锰酸钾指数等污染物质 ,是一种非常有效的预处理方法 .同时采用色 -质联机方法 ,分析了吹脱单元进出水中有机物质组分的变化 ,并探讨了去除油类有机物质的机理 .     

Nylon 6,6 modified screen printed carbon electrodes as electrochemical sensors for rapid chlorothalonil determination in water samples using differential pulse cathodic stripping voltammetry

A newly developed electrochemical sensor for chlorothalonil based on nylon 6,6 film deposited onto screen printed electrode (SPE) with electrochemical modulation of pH at the electrode/solution interface was studied for the first time. Differential pulse cathodic stripping voltammetry (DPCSV) was used to carry out the electrochemical and analytical studies. Experimental parameters such as accumulation potential, initial potential, accumulation time and pH of Britton-Robinson buffer have been optimized. Chlorothalonil gave optimum analytical signal in a medium of 0.04?M Britton-Robinson buffer at pH 6.0. A well-defined reduction peak was observed, at E_p= ?0.851 and ?0.938?V vs. Ag/AgCl (3.0?M KCl) for both bare SPE and modified SPE, respectively. The peak currents of modified SPE were significantly increased as compared to bare SPE. At the modified SPE, a linear relationship between the peak current and chlorothalonil concentration was obtained in the range from 0.1 to 2.8?×?10^?6?M with a detection limit of 1.53?×?10^?8?M (S/N=?3). The practical applicability of the newly developed method has been demonstrated on analyses of real water samples. The newly developed sensor shows good reproducibility with RSD of 3.92%. The nylon 6,6 modified SPE showed itself as promising sensor with good selectivity for chlorothalonil determination.     

纳米金修饰分子印迹聚合膜电极检测双酚A

以纳米金修饰玻碳电极为基础电极,以双酚A为模板分子,以邻氨基苯硫酚为聚合单体,采用循环伏安法电聚合制备分子印迹聚合膜,利用循环伏安和交流阻抗法研究电极的电化学特性。结果表明,双酚A在修饰电极表面的反应是一个受吸附控制的等电子、质子转移的不可逆反应。采用差分脉冲伏安法检测双酚A,线性范围为5. 0×10~(-6)mol/L～4. 0×10~(-4)mol/L,检出限为2. 3×10~(-7)mol/L。将该电极用于自来水和牛奶样品的测定,结果均为未检出,加标回收率分别为93. 5%和95. 4%,3次测定结果的RSD分别为4. 0%和5. 7%。     

苯胺在铂电极上电解特征的研究

采用循环伏安法考察了苯胺在铂电极上不同浓度、pH值和不同扫描速率等条件下的电化学反应特性。结果表明:在酸性条件下出现明显的氧化峰而中性和碱性条件下没有;在循环初期只有1个氧化峰,峰电势Ep≈1.0V,随着扫描的进行出现2个氧化峰,Ep≈1.0V,0.5V。