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排序方式: 共有742条查询结果,搜索用时 15 毫秒
1.
抗盐降滤失剂SDX的研究与应用 总被引:7,自引:2,他引:5
介绍了抗盐降滤失剂SDX的合成方法与现场应用简况,评价了SDX的抗温、抗盐、防塌及配伍性能。试验结果表明,SDX能耐150℃以上的高温,可抗盐至饱和,具有良好的降滤失和抑制性能,与其它处理剂的配伍性好,适用于各种水基泥浆。 相似文献
2.
Synthesis, characterization and catalytic application for wet oxidation of phenol of iron-containing clays 总被引:5,自引:0,他引:5
M.N. Timofeeva S.Ts. Khankhasaeva S.V. Badmaeva A.L. Chuvilin E.B. Burgina A.B. Ayupov V.N. Panchenko A.V. Kulikova 《Applied catalysis. B, Environmental》2005,59(3-4):243-248
High-surface-area pillared clays (PILC) were prepared from naturally occurring montmorillonites by exchanging interlayer ions to polyoxocations containing (i) aluminum (Al13-PILC), (ii) iron adsorpted onto Al13-PILC, and (iii) iron and aluminum located within the same complex (Fe0.8Al12.2-PILC). The obtained Fe0.8Al12.2-PILCs were characterized by DR–UV–vis and IR spectroscopy, XRD, ESR, scanning electron microscopy and low temperature N2 adsorption measurements. Important factors affecting catalyst activity and phenol removal efficiencies have been studied, i.e. the effect of pH, temperature, catalyst concentration and stability of the catalyst. 相似文献
3.
4.
A. Garea A. M. Urtiaga M. I. Ortiz A. I. Alonso J. A. Irabien 《Chemical Engineering Communications》1983,120(1):85-97
The study of the phenol separation-concentration process with the hollow fiber supported liquid membrane technology has been performed. Mixtures of kerosene and CYANEX 923 were used as liquid membrane. The extractant CYANEX 923 is characterized by a high phenol selectivity and an extremely low solubility in the aqueous phase. The introduction of CYANEX 923 in the membrane composition decreases the extractant losses from the pores of the support.
The phenol separation and simultaneous concentration process has been checked. The influences of the initial concentration of phenol in the feed solution and sodium hydroxide in the stripping phase and the membrane composition on the separation rate have been investigated in a single-pass mode. The analysis of the membrane composition influence has been performed according to the steady-state mass transfer conservation equation and the associated boundary conditions, leading to the mass transfer parameters of the process 相似文献
The phenol separation and simultaneous concentration process has been checked. The influences of the initial concentration of phenol in the feed solution and sodium hydroxide in the stripping phase and the membrane composition on the separation rate have been investigated in a single-pass mode. The analysis of the membrane composition influence has been performed according to the steady-state mass transfer conservation equation and the associated boundary conditions, leading to the mass transfer parameters of the process 相似文献
5.
A. Santos P. Yustos A. Quintanilla G. Ruiz F. Garcia-Ochoa 《Applied catalysis. B, Environmental》2005,61(3-4):323-333
Catalytic wet oxidation of phenol as a model pollutant has been performed in a three phase fixed-bed reactor (FBR) by using a commercial catalyst based on copper oxide in order to analyze the variables affecting significantly the copper leaching. It has been found that temperature has an almost negligible influence in the range studied (70–160 °C). On the contrary, an important effect of the pH value was noticed. The copper leaching reduces when the pH of the solution fed to the reactor increases, being almost negligible at pH ≥ 5. Moreover, the composition of the reaction media also influences the leaching. Higher copper concentrations than those expected by the effect of the acid aqueous media have been measured in the reactor effluent when phenol, catechol, hydroquinone, p-benzoquinone and maleic acid are present in the reaction media. On the contrary, oxalic acid has a negative influence on the leaching, since it captures the copper in solution to form copper oxalate which precipitates on the catalyst surface. For a previously acidified medium, the acetic and formic acids do not have any other effect on the copper leaching. It has been also demonstrated that as copper in solution decreases, so does phenol conversion, because the homogeneous catalysis contributes significantly to the oxidation reactions even in fixed-bed reactors. 相似文献
6.
Electrochemical pre-treatment of industrial wastewater to remove refractory and/or toxic organic components, making them more
amenable to biological treatment, is likely to be more cost-effective than using a physical or chemical process for complete
organic removal. This paper demonstrates the use of a carbon-based adsorbent material that preferentially removes chlorinated
organic compounds. Electrochemical regeneration of the adsorbent is shown to be a quick, easy and cheap process, because the
adsorbent is both highly electrically conducting and non-porous. High regeneration rates over a number of cycles were obtained
by passing a charge of 25 C g−1 through a bed of adsorbent particles, at a current density of 20 mA cm−2 for 10 min. The energy required to remove a kg of COD from an industrial wastewater was calculated to be 27 kWh. 相似文献
7.
Siyang Jiang Yan Kong Jun Wang Xiaoqian Ren Qijie Yan 《Journal of Porous Materials》2006,13(3):341-346
A series of Sn-Zn modified-MCM41 has been synthesized by direct hydrothermal method and characterized using ICP, XRD, TG/DTA,
FT-IR, HRTEM and N2-adsorption techniques. Catalytic performances of the obtained materials were evaluated in the hydroxylation of phenol with H2O2. Results indicated that all the samples exhibited typical hexagonal arrangement of mesoporous structure with high surface
area and the heteroatoms were probably incorporated into the framework of MCM41. Catalytic tests revealed that the bimetallic
incorporated materials were effective catalysts in the hydroxylation of phenol. The conversion of phenol could be reach to
56.8% for the catalysts with Sn: Zn: Si = 2.69: 4.57: 100 (molar ratio) under the optimized reaction conditions. Moreover,
the materials containing Sn and Zn exhibited higher catalytic activity than monometallic Sn and Zn modified MCM41. 相似文献
8.
Samuel J.A. Guieu Anna Maria Manotti Lanfredi Chiara Massera Laura Durn Pachn Patrick Gamez Jan Reedijk 《Catalysis Today》2004,96(4):259-264
Poly(2,6-dimethyl-1,4-phenylene ether) (PPE), which is widely used in high-performance engineering plastics, is obtained by the copper-catalyzed oxidative coupling of 2,6-dimethylphenol. The oxidative polymerizations have been carried out in acetonitrile with structurally related [copper-(N,O-containing ligand)] complexes as the catalyst precursor compounds, which appeared to be of great interest for a better understanding of the factors influencing the catalytic activities. Steric effects (influence of a methyl group close to the metal center; ligands 4–7) or electronic effects (imino versus amino group; ligands 4, 5, 8 and 6, 7, 9, respectively) on the polymerization rates have been demonstrated. The use of mono- or dinucleating ligands has strengthened the proposed mechanism of the reaction involving dinuclear active species. 相似文献
9.
10.
炼油厂碱水生化预处理研究 总被引:4,自引:0,他引:4
采用曝气生物滤池氧化工艺对炼油厂碱水进行预处理。研究了污水中的COD、硫化物、酚、油等污染物浓度、污水在生物滤池中的水力停留时间(HRT)、反冲洗等参数对处理效果的影响。实验结果表明,污水中的硫化物比酚更容易在滤池中被生物降解,当停留时间为10 h时,污水中的COD、硫化物、油和酚的平均去除率分别为73.4%、98.6%、90.1%和79.7%。 相似文献