NiO掺杂InVO4光催化降解甲酸水溶液产氢的研究

以有机污染物为电子供体可达到制氢与治污的双重目标.通过高温固相法制备了新型NiO/InVO4复合光催化剂.采用XRD,SEM,UV-VIS,BET等测试手段对复合光催化剂的物理和光学性质进行了表征,考察了NiO/InVO4复合光催化剂降解甲酸水溶液制氢的光催化反应.结果表明:NiO/InVO4复合光催化剂为正交晶相结构...     

三维电极-铁炭微电解法组合工艺处理黄连素废水

该文研究了三维电极-铁炭微电解复合法对难降解有机物黄连素模拟废水的处理.结果表明三维电极电解技术对黄连素具有较高的脱色效果,在最佳处理条件下黄连素废水脱色率为95％,而COD的去除率仅为38.5％.三维电极与铁炭微电解法复合处理,则可以明显提高黄连素模拟废水COD去除率和废水的可生化性.在最佳条件下COD去除率达到72...     

压缩式热泵精馏中的工质选择

热泵精馏是一项高效节能技术。本文分析了压缩式热泵精馏中不同类型工质应用的特点,比较了它们的实际适用条件,这埘推广热泵精馏的工业应用有一定的指导意义。     

硝酸铵-有机物体系稳定性的实验研究

以DSC热分析和雷管感度测定方法研究了硅油、磷酸三乙酯、木粉、蔗糖等有机物与硝酸铵按照零氧平衡组成体系的稳定性。木粉和蔗糖中存在的羟基等还原性基团显著降低了体系的热稳定性;硅油和磷酸三乙酯的化学性质尽管稳定,但与硝酸铵适当混合仍具有雷管起爆感度。     

Water Quality of the North Sea: Concerns and Control Measures

The quality of the North Sea has become a topic high on the political agenda. Various claims have been made about quality deterioration but hard evidence has been less available. The paper reviews these concerns, summarizes the scientific evidence and considers the specific contaminants involved, together with estimates of inputs and the available controls. The new initiatives stemming from the Ministerial conferences and the evolving legislation should go a long way towards producing reassurance on the one hand and solutions to real problems on the other.     

Capacity of activated carbon derived from pistachio shells by H3PO4 in the removal of dyes and phenolics

Two activated carbons were obtained from pistachio shells by impregnation with H₃PO₄ under standard conditions of acid concentration (50 wt%) and heat treatment at 773 K for 2 h. The soaking time was 24 and 72 h for the two samples before thermal pyrolysis. Analysis of the N₂/77 K adsorption isotherms proved that both were highly adsorbing carbons with considerable microporosity, and that the prolonged contact with activant enhanced total porosity (surface area and pore volume) and increased the amount of mesoporosity. Adsorption isotherms of probe molecules, viz methylene blue (MB), rhodamine B (RB), phenol (P) and p‐nitrophenol (PNP), were determined at room temperature, from aqueous solutions. Both the Langmuir and Freundlich model adsorption equations show satisfactory fit to experimental data. Both carbons exhibit similar adsorption parameters irrespective of their porosity characteristics. The sequence of uptake per unit weight was: PNP > MB > RB > P. Low affinity towards phenol may be associated with its competition with water molecules which are more favourably attracted to the acid surface which has a high oxygen functionality. Preferred adsorption in the order PNP > MB > RB is proposed to be a function of carbon porosity, related to the increased molecular dimensions of the solutes. Adsorption from a binary mixture of equal concentrations of MB and RB showed reduced uptake for both sorbates in comparison to the single component experiments. RB removal surpasses that of MB in the binary test and may be attributed to lower water solubility and higher molecular dimensions. Copyright © 2003 Society of Chemical Industry     

Polarographic study of the interaction between humic acids and other surface-active organics in river waters

The surface activity of river water humic acids (HA) has been studied using the principle of suppression of polarographic streaming maxima by organics that adsorb on the mercury electrode. HA isolated from river water by hydrophobic adsorption onto Amberlite XAD-2 were found to be almost four times more effective at maximum suppression than natural river water organics as a whole. Ultraviolet and fluorescence measurements indicated that 25–30% of total dissolved organics were in the hydrophobic HA fraction. HA's were found to interact interfacially with other more hydrophilic organic components with a 50% decrease in their surface activity. Similar interactions were found with synthetic surface-active materials.     

Persistent chemicals in pulp mill effluents: Occurrence and behaviour in an activated sludge treatment plant

In wastewater effluents of a Swiss pulp mill more than 50 organic chemicals were identified including chlorinated phenols, chloroform, chlorinated terpenoids and chlorinated resin acids. Quantitative determinations were carried out to investigate the behaviour of the most abundant constituents during wastewater treatment in an activated sludge process. In particular, the chlorinated compounds were only partly eliminated. The lipophilic chlorinated phenols were physically absorbed to some extent into the activated sludge biomass. The importance of this nonbiological elimination mechanism was evaluated by applying distribution coefficients between activated sludge particles and water which were determined for a series of chlorinated phenols. Chloroform and other purgeable compounds were removed mainly by transfer into the ambient air. The impact of the persistent wastewater constituents on the water quality in the receiving River Aare was assessed. It was estimated that the concentrations of chlorinated phenols in the river caused by the discharge of the treated pulp mill wastewater are about 10 times lower than the levels of pentachlorophenol which typically occur in Swiss rivers receiving effluents from municipal wastewater treatment plants.     

Distribution of Mercury,Trace Organics,and Other Heavy Metals in Detroit River Sediments

In 1980 the Ontario Ministry of the Environment carried out a surficial bottom sediment survey of the Detroit River. The survey was designed to update changes in sediment mercury levels from a 1970 study, and to determine the spatial distribution of trace organics and other heavy metals as a baseline for future investigations. The contamination of sediments along the Ontario shoreline of the river was localized near known inputs such as Little River, the West Windsor sewage treatment plant, Turkey Creek, and Riviere aux Canards. Almost the entire U.S. shoreline sediments exhibited elevated levels (above provincial dredging guidelines) of contaminants such as heavy metals and PCBs. Levels of one order of magnitude higher than those on the Canadian shore were prevalent along the U.S. shore. Mercury levels exhibited a substantial decline during the period 1970–1980. Increases in chromium, copper, lead, and zinc in the vicinity of the mouth of the Rouge River along the U.S. shoreline during the same period suggest both recent and continuing inputs from industrial and municipal sources.     

废水中难降解物质生物降解的有利因子

一级基质的加入能产生足够能量供难降解物质进行偶发生物降解；可充分利用种间协同作用完成对难降解物质的降解；驯化是稳定和有效处理有毒物质废水的关键；充足的微量无机营养，尤其是微量金属元素对微生物的代谢是重要的。