Data Mining - Concepts and Techniques.

International Journal of Computer and Applications

Advanced oxidation processes for in-situ production of hydrogen peroxide/hydroxyl radical for textile wastewater treatment: A review

Evaluation of zeolite A for the sorptive removal of Cs+ and Sr2+ ions from aqueous solutions using batch and fixed bed column operations

The protection and conservation of natural resources is one of the main priorities of modern society. Water is perhaps our most valuable resource, and thus should be recycled. Many of the current recycling techniques for polluted water only concentrate the pollutant without degrading it or eliminating it. In this sense, advanced oxidation processes are possibly one of the most effective methods for the treatment of wastewater containing organic products (effluents from chemical and agrochemical industries, the textile industry, paints, dyes, etc.). More conventional techniques cannot be used to treat such compounds because of their high chemical stability and/or low biodegradability. This article describes, classifies, and analyzes different types of advanced oxidation processes and their application to the treatment of polluted wastewater.

Advanced Oxidation Processes for Wastewater Treatment: State of the Art

Mesoporous silica molecular sieves MCM-41 containing zinc and aluminum ions (Zn-Al-MCM-41) with Si/(Zn + Al) ratio equal to 340 and 380 and only aluminum ions with Si/Al ratio equal to 93 and 104, respectively, were synthesized under hydrothermal conditions using cetyltrimethylammonium (CTMA + ) surfactants as template in the absence of auxiliary organics. The mesoporous materials, viz. Zn-Al-MCM-41 and Al-MCM-41 were characterized using several techniques, e.g. powder X-ray diffraction (XRD), nitrogen adsorption measurements, Fourier transform-infra red spectroscopy (FT-IR) and thermogravimetric–differential thermal analyzer (TG–DTA). XRD studies indicated that the calcined materials had the standard MCM-41 structure. Nitrogen adsorption was used to determine specific surface area, pore volume, and pore size distribution in the Zn-Al-MCM-41(340), Zn-Al-MCM-41(380), Al-MCM-41(93) and Al-MCM-41(104) mesoporous molecular sieves. FT-IR studies showed that Zn and Al ions were incorporated into the hexagonal mesoporous structures of Zn-Al-MCM-41 and Al-MCM-41. The thermal stability of the as-synthesized materials was studied using TG–DTA. The effect of reaction temperature, WHSV and isopropanol:toluene ratios on the selectivity of p-cymene were studied. The Zn-Al-MCM-41(340) catalyst containing larger pore size and higher number of Bronsted acid sites was found to be more effective in the alkylation of alkyl aromatics, for example, in the production of p-cymene from toluene, using 2-propanol as the alkylating reagent. The selectivity of p-cymene under varying experimental condition, viz. effect of reaction temperature, WHSV and ratio of isopropanol:toluene for the various catalysts follows the sequence Zn-Al-MCM-41(340 )> Al-MCM-41(93 )> Zn-Al-MCM-41(380 )> Al-MCM-41(104). © 2002 Elsevier Science B.V. All rights reserved.

Synthesis, characterization and catalytic application of MCM-41 mesoporous molecular sieves containing Zn and Al

Synthesis and characterization of Mn–MCM-41and Zr–Mn-MCM-41

Mesoporous aluminosilicate Al-MCM-41 with Si/Al=93 and 104 were synthesized using cetyltrimethylammonium bromide as the structuring agent and the materials were characterized using several techniques. The mesoporous structure was confirmed by X-ray diffraction (XRD) technique. The surface area, pore size and wall thickness was calculated by BET equation and BJH method using nitrogen sorption technique. Fourier transform-infrared (FT-IR) spectroscopy was used in order to obtain information on incorporated aluminum atoms in the mesoporous structure of Al-MCM-41. Thermogravimetric–differential thermal analyzer (TG–DTA) was used to determine the thermal stability of the materials. The effect of reaction temperature, WHSV and isopropanol:toluene ratios on the selectivity of p-cymene were studied. The Al-MCM-41 (93) catalyst exhibited excellent selectivity in the production of p-cymene by the isopropylation of toluene using isopropanol as the propylating agent.

Pradeep Kumar Sinha

Papers

Synthesis, characterization and catalytic application of MCM-41 mesoporous molecular sieves containing Zn and Al

Synthesis and characterization of Mn–MCM-41and Zr–Mn-MCM-41

Comparison of mesoporous Al-MCM-41 molecular sieves in the production of p-cymene for isopropylation of toluene

Treatment of radioactive liquid waste containing caesium by indigenously available synthetic zeolites: A comparative study

Ultrasonic treatment of liquid waste containing EDTA