نتایج جستجو برای: zeolite x
تعداد نتایج: 631184 فیلتر نتایج به سال:
The activation of soil-fixed phosphorus is a long-term concern in soil science. In order to enhance the activation effect to soil-fixed phosphorus in red soil, different modified zeolite, through physical, chemical method and the associated both physics and chemistry, was used in this paper. The results showed as following: 1) the activated ability to soil-fixed phosphorus in red soil for modif...
Mesoporous aggregates of nanocrystalline zeolites with MFI and BEA frameworks have been synthesized using a one-pot and single structure directing agent. The effect of different reaction conditions, such as temperature, time, pH and water content, on the particle size, surface area and mesopore volume has been studied. Nanocrystalline and mesoporous ZSM-5, β and Y zeolites were modified with di...
In this work, a flow injection analysis (FIA) method for the trace determination of lead, cadmium, nickel and cobalt in natural waters by formation of neutral chelates with ammonium pyrrolidine dithiocarbamate (APDC) was developed. The neutral chelates formed was retained in a mini-column packed with Linde type A zeolite (LTA) and type Y Faujasite zeolite (FAU) and then eluted with methyl isobu...
The ion exchange of Na for Cr/K, Cr/Mg and Cr/Ca in Y and X zeolites was studied using breakthrough curves. It was observed that Cr ions were able to remove some competitive ions that had already been exchanged at the zeolitic sites, producing a sequential ion exchange. Some mass transfer parameters such as length of unused bed, overall mass transfer coefficient, operational ratio and dimension...
Methanol is an important feedstock in numerous catalytic processes. It can be produced via Fischer-Tropsch reaction from synthesis gas [1] and its further transformation to hydrocarbons up to C10 is the basis of several industrially important reactions as for instance the Methanol to Gasoline process [2]. Methanol can also be used as an alkylating agent for aromatic compounds in zeolite-catalys...
A micro-spectroscopic method has been developed to probe the accessibility of zeolite crystals using a series of fluorescent 4-(4-diethylaminostyryl)-1-methylpyridinium iodide (DAMPI) probes of increasing molecular size. Staining large zeolite crystals with MFI (ZSM-5) topology and subsequent mapping of the resulting fluorescence using confocal fluorescence microscopy reveal differences in stru...
The development of green, selective, and efficient catalysts, which can aerobically oxidize a variety of alcohols to their corresponding aldehydes and ketones, is of both economic and environmental significance. We report here the synthesis of a novel aerobic oxidation catalyst, a zeolite-confined nanometer-sized RuO(2) (RuO(2)-FAU), by a one-step hydrothermal method. Using the spatial constrai...
The efficiency of innovative matrices for immobilizing cesium is presented in this work. The matrix formulation included the use of fly ash belite cement (FABC-2-W) and gismondine-type Na-P1 zeolite, both of which are synthesized from fly ash of coal combustion. The efficiency for immobilizing cesium is evaluated from the leaching test ANSI/ANS 16.1-1986 at the temperature of 40 degrees C, from...
The structure of the as-made, hydrated form of ECR-40C, synthesized in the presence of (2-hydroxyethyl) trimethylammonium (HTMA) ions as an organic structure-directing agent (OSDA) and 2 wt% (relative to alumina in the synthesis mixture) of aluminosilicate zeolite UZM-22 with the MEI topology as seeds, has been determined using synchrotron powder X-ray diffraction and Rietveld analyses. Two dif...
Microwave zeolite synthesis has been shown to greatly reduce crystallization time. Although, fast efficient syntheses and quality crystalline products are widely reported(1), the mechanism leading to the formation of zeolites under microwave heating is not fully understood. Cundy(1) has reviewed the literature and concludes that the likely processes specific to microwave synthesis of zeolites a...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید