The development of energy efficient, reduced-weight, regenerable adsorption systems for removal of environmental contaminants, such as CO2 in spacecraft cabin air, chemical/biological warfare agents (CWA), and toxic industrial chemicals (TICs) is an area of continuing interest to NASA and Department of Defense, respectively. Precision Combustion, Inc. (PCI) has designed and developed a sorption...

Ammonium removal from aqueous solution by a natural ion-exchange resin was investigated by considering the factors affecting the ammonium-exchange capacity including the zeolites’ particle size, the loading flow rates and the impact of a number of regenerations upon the ion-exchange capacity. The resin column was exhausted by downflow at 10, 25, 50 and 75 bed volume (BV)/h, until effluent ammon...

The synthesis of NaY-zeolite was performed hydrothermally. preparation the bifunctional catalysts achieved by loading NH4Y-zeolite with a cheap Zr metal, as second tiny amounts Pt to compose Pt-Zr/Y-zeolite catalyst. Different characterization methods (i.e., XRD, SEM, EDX, BET, and AFM) were used investigate catalyst properties. catalytic performance studied performing hydroisomerization n-hept...

While microwave enhancement of chemical syntheses has been demonstrated for a broad variety of chemical reactions, there is no accepted universal mechanism. Is the enhancement due to more efficient heating, to overheating, to nonuniform heating, or to nonthermal effects? Analyses are complicated due to the often significant spatial and temporal temperature variations in microwave reactor system...

The technology follows a sequence of steps: 1) place a confinement template proximal to the disposal structure; 2) drive a primary confinement €I-beam and sheet piling proximal to and below the underground structure and contaminant plume; 3) inject a primary low-cost inorganic polymer below the contaminated geologic media; 4) injectMood the contaminant plume; 5) inject cements and sequestering ...

background lead poisoning impairs memory and learning. objectives the protective effect of natural zeolite clinoptilolite on memory and learning impairment in rats exposed to lead acetate was investigated. materials and methods 60 male wistar rats in six groups treated for 2 months with diets contained different ratios of natural zeolite(i.e. 5% or 12.5%), and %0.2 lead acetate (la) concentrati...

Cylindrical adsorbers are usually used for pressure swing adsorption (PSA) processes. In this study, the flat-box adsorbers which stack together replaced the traditional cylindrical adsorbers. Simulation was performed for separation of air (21% oxygen; 79% nitrogen) in Skarstrom cycle. Instantaneous equilibrium between solid and gas phase with non-isothermal operation were assumed and the bed p...

Oxygen is one of the most important products in chemical industries. This chemical element is used in various processes such as: refinery industries, manufacturing metal and other industrial operations. For instance, oxygen with high purity is utilized in different chemical processes like: steel construction, paper industries, wastewater treatment and glass production. In 1907, oxygen was produ...

This work presents the recovery of biosorption supports as an alternative source of benign production of heterogeneous catalysts for oxidation reactions in mild conditions. Cr-containing FAU zeolite, in sodium form (NaY) and in proton form (HY), was recovered from biosorption studies and reused as support for the preparation of heterogeneous catalysts by the flexible ligand method, using 1,3-di...

The aim of this study is to investigate ammonium removal from a wastewater resulted after homogenization and anaerobic digestion of a mixture of wastes and wastewater from animal processing units and sewage sludge, by using natural zeolite clinoptilolite. Batches as well as closed loop fixed bed system (CLFB) are studied, offering an alternative to conventional fixed bed systems. The experiment...