This study reports on the EPR of C r 5 + and C u 2 + ions, introduced by solidand liquid-state reactions with the synthetic zeolites 3A, 4A and 5A, and the natural zeolite clinoptilolite. C r 3 + was oxidized to Cr 5 + in the samples, the coordination around Cr 5 + being square pyramidal. Superhyperfine (shf) interaction of Cr with A1 nucleus was observed in both solidand liquid-stateintroduced...

considering the point that the existence of heavy metals in the wastewater are so dangerous forthe environment and it would have many bad consequences for all the creatures including human beings, wemust try out the ways that make us capable of adsorbing these heavy metals. in order to accomplish this goal we should use a method called adsorbing. in this study the adsorption of copper ions in h...

A natural zeolite (Z-N), rich in clinoptilolite, was modified (Z-Al) by incorporation of hydrated aluminum oxide (HAlO) for the simultaneous phosphate and ammonium removal. The incorporation of surface hydroxyl groups (≅Al-OH) into the zeolite structure, as active groups for phosphate removal, was characterized by acid-base titrations (pHPZC=4.5±0.2). The phosphate sorption increases from 0.6 m...

This study investigated the photocatalytic behaviors for the nanocomposite of TiO2 P25 and Semnan natural zeolite in the decomposition of tetracycline under visible light in an aqueous solution. The structural features of the composite were investigated by a series of complementary techniques that included X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), scanning elec...

The aim of this study was to prepare and characterize a potential drug support system based on surfactant/zeolite composites for anti-inflammatory drugs. In order to increase the adsorbing capacity the external surface of the natural zeolite clinoptilolite was modified with benzalkonium chloride in the treatments raging from 100% to 300% of the zeolite external cation exchange capacity. Adsorpt...

The potential long term environmental impacts of a landfill on groundwater quality depend on its liner material properties. In case synthetic liner materials are damaged during the construction or operation, many of the original chemical and biological constituents are removed by filtration and the adsorptive action of natural liner materials such as natural zeolite, perlite and bentonite miner...

introduction: soil structural stability affects the profitability and sustainability of agricultural systems. particle size distribution (psd) and aggregate stability are the important characteristics of soil. aggregate stability has a significant impact on the development of the root system, water and carbon cycle and soil resistance against soil erosion. soil aggregate stability, defined as t...

background: no2 is a poisonous gas that potential to cause major threat to human being health and the environment, as a result, removing this gas from environment seems to be essential. methods: the study aimed to remove this gas from environment using iranian natural zeolite, clinoptilolite. after crushing and preparing two sizes of 1 and 2 mm zeolite they were activated in 380 to 420 ºc for 2...