background aromatic organic solvents are extensively used in various industries. xylene is a colorless, transparent liquid, with the characteristic odor of the aromatic hydrocarbons family, which is widely used in industries. adsorption is a conventional method of purifying polluted air containing volatile organic compounds (vocs). zeolite has many unique properties such as high capacity, molec...

background: the removal of toxic metals from sewage and wastewaters is one of the most important concerns in the twenty first century. the removal of poisonous cr(vi) from aqueous solution by different low-cost available nanoporous adsorbents was investigated in the present study.  methods: fumed silica, bentonite (bn), hydrotalcite (ht), mcm-41, na-y, mordenite (mor) and sapo-34 were used at d...

Zeolites due to their structures can be used as molecular sieves for purification of materials and solutions. Zeolites with PHI and SOD structure are so common and applicable for this purpose. Hydroxy sodalite and phillipsite are the more abundant members of zeolites which display good selectivity for very small molecules and some ions such as Sr, Pb, Zn, Cu and Rb. There is not any pure natura...

Solid (heterogeneous) catalysts (1–4) are favored in industrial processes because they eliminate the need to separate the catalyst from the products. Heterogeneous catalysts can be solid acids, bases, supported metals, mixed metal oxides, or multifunctional materials. Commercial processes based on solid acids outnumber all others, and zeolites (and closely related materials) are usually the sol...

Self-pillared pentasil (SPP) zeolite is a hierarchically-structured zeolite comprised of single-unit cell thick MFI nanosheets arranged in a ‘‘house of cards’’ structure. The nucleation and growth of SPP proceeds through three phases involving the evolution of precursor amorphous nanoparticles to MFI nanosheets and then rotational intergrowth of sheets to produce the SPP morphology. This paper ...

Using hydrothermal synthesis process a series of Mobil Five (MFI) zeolites were synthesized with silica to alumina ratio (SAR) of 50, 100 and 200. The synthesized MFI zeolites were used to exchange with 0.5%, 1.0% and 2.0% Ca(NO3)2 solutions for modification of MFI zeolites to Ca-MFI zeolite. The formation of MFI zeolite phases was identified by XRD and FT-IR analysis. TGA...

The formation of cis-anethole and various dimers as a result of the exposure of trans-anethole to microporous solid acids (dealuminated HY zeolites), or UV-Vis irradiation was established by means of high resolution gas chromatography coupled to mass spectrometry. 3,4-bis-(4-Methoxyphenyl)-(E)-hex-2-ene was the most abundant compound among eight different methoxyphenyl-disubstituted hexenes pro...

The present investigation has been carried out to assess a chromium, cobalt, and cadmium from wastewaters by natural and modified zeolites were examined by using batch type method. A clinoptilolite type synthetic / natural zeolite were pretreated with HCl and HNO3 to improve the adsorption capacity for heavy metals. The removal efficiencies and kinetics of heavy metals such as chromium, cobalt ...

Supercritical fluids and ionic liquids offer attractive opportunities for modifying and applying zeolites as adsorbents and catalysts. After a brief introduction to the most important properties of these solvents, examples of zeolite applications in supercritical fluids and ionic liquids from the recent literature are discussed. Particular emphasis is put on the influence of reaction media on t...

Ion exchange properties of five different Japanese natural zeolites in seawater were examined. Sodium ions could be reduced by all zeolites, although anions, Cl(-) and SO(4)(2-), in seawater showed barely changes. Natural zeolite desalination treatment mainly depends on the ion exchange between Na(+), K(+) and Mg(2+) in seawater and Ca(2+) in natural zeolite. This study found that mordenite ...