Oxidation of diesel soot on binary oxide CuCr(Co)-based monoliths

Binary oxide systems (CuCr₂O₄, CuCo₂O₄), deposited onto cordierite monoliths of honeycomb structure with a second support (finely dispersed Al₂O₃), were prepared as filters for catalytic combustion of diesel soot using internal combustion engine's gas exhausts (O₂, NO_x, H₂O, CO₂) and O₃ as oxidizing agents. It is shown that the second support increases soot capacity of aforementioned filters, and causes dispersion of the particles of spinel phases as active components enhancing thereby catalyst activity and selectivity of soot combustion to CO₂. Oxidants used can be arranged with reference to decreasing their activity in a following series: O₃ ? NO₂ > H₂O > NO > O₂ > CO₂. Ozone proved to be the most efficient oxidizing agent: the diesel soot combustion by O₃ occurs intensively (in the presence of copper chromite based catalyst) even at closing to ambient temperatures. Results obtained give a basis for the conclusion that using a catalytic coating on soot filters in the form of aforementioned binary oxide systems and ozone as the initiator of the oxidation processes is a promising approach in solving the problem of comprehensive purification of automotive exhaust gases at relatively low temperatures, known as the “cold start” problem.     

Fe-Mn/AC催化湿式过氧化氢氧化间甲酚

采用等体积浸渍法制备了一种新型Fe-Mn/AC催化剂,应用于催化湿式过氧化氢氧化(CWPO)间甲酚废水.通过SEM和XRF表征了其表面形态结构和元素组成,通过穆斯堡尔谱分析了催化剂中铁离子的存在形态,结果表明,新型Fe-Mn/AC催化剂中的铁以二价铁、三价铁以及四氧化三铁的形式存在.通过正交实验考察了CWPO降解间甲酚的影响因素,结果表明,各因素对间甲酚转化率影响的大小顺序依次为:底物初始p H值反应温度反应时间催化剂投加量.通过正交实验得到CWPO降解间甲酚的最佳反应条件.当间甲酚浓度为100 mg·L-1、反应温度为40℃、反应时间为40 min、催化剂投加量为0.6 g·L-1及底物初始p H值为3时,间甲酚转化率为99.8%,TOC去除率为28.3%.气相色谱/质谱联用没有检测到中间产物,气相色谱检测到CWPO降解间甲酚中间产物主要为乙酸和丙酸.     

The synergistic interaction of Nickel(II) with dna damaging agents

In this report we present several examples in which nickel(II) in combination with DNA damaging agents caused an enhanced or synergistic biological response using several different endpoints. These examples of Ni(II) toxicity represent several approaches designed to understand the genotoxicity of Ni(II) as well as several other metal ions. They are discussed in this report as a partial basis for our hypothesis that Ni(II) may alter the cellular processing of DNA damage at some common point in the pathway for DNA repair of several different agents. In cultured Chinese hamster cells DNA damage by Ni(II) ions was not readily demonstrated by the method of alkaline elution, but pretreatment of cells with Ni(II) before X‐irradiation produced an enhanced amount of strand breaks compared to the amount produced by X‐rays alone. A synergistic enhancement of cell transformation of Syrian hamster embryo cells was observed for combined treatments of Ni(II) and benzo(a)pyrene. The nickel enhancement of mutagenesis by ultraviolet light was demonstrated for the bacterial gene gpt stably integrated into the Chinese hamster V79 genome.     

Recovery of lithium and cobalt from waste lithium ion batteries of mobile phone

In view of the stringent environmental regulations, availability of limited natural resources and ever increasing need of alternative energy critical elements, an environmental eco-friendly leaching process is reported for the recovery of lithium and cobalt from the cathode active materials of spent lithium-ion batteries of mobile phones. The experiments were carried out to optimize the process parameters for the recovery of lithium and cobalt by varying the concentration of leachant, pulp density, reductant volume and temperature. Leaching with 2 M sulfuric acid with the addition of 5% H₂O₂ (v/v) at a pulp density of 100 g/L and 75 °C resulted in the recovery of 99.1% lithium and 70.0% cobalt in 60 min. H₂O₂ in sulfuric acid solution acts as an effective reducing agent, which enhance the percentage leaching of metals. Leaching kinetics of lithium in sulfuric acid fitted well to the chemical controlled reaction model i.e. 1 ? (1 ? X)^1/3 = k_ct. Leaching kinetics of cobalt fitted well to the model ‘ash diffusion control dense constant sizes spherical particles’ i.e. 1 ? 3(1 ? X)^2/3 + 2(1 ? X) = k_ct. Metals could subsequently be separated selectively from the leach liquor by solvent extraction process to produce their salts by crystallization process from the purified solution.     

PKS控制系统在锅炉烟气脱硝处理中的应用

Honeywell PKS控制系统应用于循环流化床锅炉脱硝处理,可实现工艺数据的集中显示和工艺指标的集散控制,特别是在关键设备如稀释风机的互备联锁控制、氨流量的自动调节、吹灰器的顺序控制等方面,利用PKS系统丰富的功能块,实现了控制策略的组态和优化,保证了生产安全稳定运行。     

La2O3—ZrO2缺陷萤石型燃烧催化剂的制备

缺陷萤石型Ｌａ２Ｏ３－ＺｒＯ２固溶体的催化燃烧活性受制备条件的影响，本文通过对其共沉淀前体的表面结构和热分解过程的分析，发现共沸蒸馏的办法可以有效地控制前体表面羟基的缩合过程，减少团聚，保持前体中金属离子均匀分散，为生成缺陷有序的烧结石型的Ｌａ２Ｚｒ２Ｏ７复氧化物提供了可能。复合氧化物固溶体的表面阳离子配置情况与样品的催化氧化性能密切相关，软团聚前体的烧结产物对甲烷燃烧反应具有更高的催化活性。     

氢氧化钠-膜过滤法处理含镍电镀废液

介绍了氢氧化钠－膜过滤法处理含镍电镀废液新工艺，并确定了主要的技术参数。该工艺具有回收NiSO4纯度高，出水Ni^2 可实现稳定达排放等优点。     

流向变换等离子体催化系统去除甲苯

将低温等离子体、催化和流向变换技术相结合,以反应系统参数（接地极方式、反应管壁厚）和电源参数（电压、频率）为影响因素,探究了上述因素对系统温度升高（△T）、放电能量密度（SED）和能量效率（EE）的影响,考察了不同条件对甲苯的去除效果（η）和反应产物的影响.结果表明：流向变换低温等离子体协同催化系统中,甲苯去除效果最好,能量利用率最高,为3.76g/（kW·h）.连续升压时,3种接地条件下的温度升高△T差距不明显;铝箔接地时,O₃浓度最高、甲苯去除率η、SED和EE最高;增加反应管壁厚,系统△T、η、SED和EE减小.3种技术结合时,NO₂生成浓度低、有机副产物生成种类较少,CO₂选择性高,甲苯矿化率最高.固定频率,改变电压时,△T、η、SED与电压值呈正比,EE则相反,铝箔接地时,17kV时△T达到110.7℃,η达到74.05%;副产物O₃浓度先上升后下降,最终趋于0mg/m³;固定电压,改变频率时,变化规律一致.     

Enhanced solar-light-driven photocatalytic properties of novel Z-scheme binary BiPO4 nanorods anchored onto NiFe2O4 nanoplates: Efficient removal of toxic organic pollutants

Global environmental problems have been increasing with the growth of the world economy and have become a crucial issue. To replace fossil fuels, sustainable and eco-friendly catalysts are required for the removal of organic pollutants. In this study, nickel ferrite (NiFe₂O₄) was prepared using a simple wet-chemical synthesis, followed by calcination; bismuth phosphate (BiPO₄) was also prepared using a hydrothermal method. Further, NiFe₂O₄/BiPO₄ nanocomposites were prepared using a hydrothermal technique. Numerous characterization studies, such as structural, morphology, surface area, optical, photoluminescence, and photoelectrochemical investigations, were used to analyze NiFe₂O₄/BiPO₄ nanocomposites. The morphology analysis indicated a successful decoration of BiPO₄ nanorods on the surface of NiFe₂O₄ nanoplate. Further, the bandgap of the NiFe₂O₄/BiPO₄ nanocomposites was modified owing to the formation of a heterostructure. The as-prepared NiFe₂O₄/BiPO₄ nanocomposite exhibited promising properties to be used as a novel heterostructure for tetracycline (TC) and Rhodamine B (RhB) removal. The NiFe₂O₄/BiPO₄ nanocomposite degrades TC (98%) and RhB (99%) pollutants upon solar-light irradiation within 100 and 60 min, respectively. Moreover, the trapping experiments confirmed the Z-scheme approach of the prepared nanocomposites. The efficient separation and transfer of photogenerated electron-hole pairs rendered by the heterostructure were confirmed by utilizing electrochemical impedance spectroscopy, photocurrent experiments, and photoluminescence. Mott–Schottky measurements were used determine the positions of the conduction and valence bands of the samples, and the detailed mechanism of photocatalytic degradation of toxic pollutants was projected and discussed.