Διατριβές για τον Ζεόλιθο

Mark W. Ackley, Salil U. Rege, Himanshu Saxena Praxair, Inc., 175 East Park Drive, Tonawanda, NY 14151, USA Received 22 July 2002; received in revised form 21 October 2002; accepted 22 October 2002 Abstract There are many natural zeolites of which a small number including clinoptilolite, chabazite, mordenite, erionite, ferrierite and phillipsite offer the greatest promise for gas separation. Patents and other literature have been surveyed to identify the bulk separation and purification processes for which these zeolites have potential. The abundance and low raw material cost of natural zeolites have rarely offset such disadvantages as variable composition, low purity ... Διαβάστε περισσότερα

More than 85 percent of all wood-based materials are manufactured using adhesives containing formaldehyde. Increasingly strict regulations concerning these emissions have been creating major challenges for adhesive manufacturers and the wood-based product industry since the 1970s. The primary objective of the project was to considerably reduce the formaldehyde emissions from wood-based products by adding small amounts of absorbers on the basis of zeolites with simultaneous catalytic effect. Modifizierung einer Zeolithoberfläche mit 3-Aminopropyltriethoxysilan (nach Liu et al. 1997). Adhesives containing formaldehyde are, compared to other suitable types of adhesive, extremely economically-priced and are therefore indispensible for the wood-based materials industry in ... Διαβάστε περισσότερα

D. Papaioannou, P.D. Katsoulos, N. Panousis *, H. Karatzias Clinic of Productive Animal Medicine, School of Veterinary Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece Received 4 April 2005; received in revised form 12 May 2005; accepted 12 May 2005 Available online 28 June 2005 Abstract The present review comments on the role of the use of zeolites as feed additives on the prevention and/or the treatment of certain farm animal diseases. Both natural and synthetic zeolites have been used in animal nutrition mainly to improve performance traits and, based on their fundamental physicochemical properties, they were also tested ... Διαβάστε περισσότερα

Evaluating Green Compost and Zeolite to Enhance Soil Quality for Dubai Sustainable City Language: English Thematic Areas: Natural Resources Management in Marginal Environments Problem Overview: In the United Arab Emirates, the soils are dominantly sandy and infertile and require frequent irrigation to maintain a healthy landscape under hot climate. However, little has been done in this respect on UAE soils for urban landscaping projects such as Dubai Sustainability City, and hence this subject has formed the focus of this study, involving zeolite and compost produced by Tadweer Waste Treatment L.L.C. in different quantities, tested in the laboratory and greenhouse trial. ... Διαβάστε περισσότερα

Article Synopsis The International Symposium on Zeolite and Microporous Crystals 2015 (ZMPC2015) was held at the Sapporo Convention Center, Japan, from 28th June to 2nd July 2015 and had 435 attendees from 32 countries, with 75% from Japan, China, Korea or Taiwan. 396 presentations covered all aspects of zeolites and microporous crystals over four days. Catalysis and synthesis were the two main themes (46% of all presentations) with the others being: new porous materials; membranes and films; adsorption and diffusion; characterisation; novel applications; industrial applications; layered materials; computational chemistry; post-synthetic treatment; crystallography; and ion exchange. There were six plenary talks ... Διαβάστε περισσότερα

Abstract Silicon (Si) is the most abundant element present in the Earth’s crust besides oxygen. However, the exact biological roles of silicon remain unknown. Moreover, the ortho-silicic acid (H4SiO4), as a major form of bioavailable silicon for both humans and animals, has not been given adequate attention so far. Silicon has already been associated with bone mineralization, collagen synthesis, skin, hair and nails health atherosclerosis, Alzheimer disease, immune system enhancement, and with some other disorders or pharmacological effects. Beside the ortho-silicic acid and its stabilized formulations such as choline chloride-stabilized ortho-silicic acid and sodium or potassium silicates (e.g. M2SiO3; M= ... Διαβάστε περισσότερα

Takahiko Moteki and Raul F. Lobo Chem. Mater., Just Accepted Manuscript DOI: 10.1021/acs.chemmater.5b04439 Publication Date (Web): December 17, 2015 Copyright © 2015 American Chemical Society Abstract The fluoride method of zeolite synthesis yields materials with unique characteristics such as high Si/Al ratio, large crystal size, and hydrophobic properties, and it has been advantageous for the synthesis of new pure-silica or high-silica zeolites. It is often difficult, however, to incorporate aluminum—and thus bring about useful catalytic properties—in materials prepared through the fluorite method. In this report we show that FAU-type zeolites are an effective source of aluminum to the growing crystals ... Διαβάστε περισσότερα

Frederick A. Mumpton, Department of the Earth Sciences, State University College, Brockport, NY 14420 Introduction As agriculturalists the world over increase their effort to expand crop and animal production, more and more attention is being paid to various mineral materials as soil amendments and as dietary supplements in animal husbandry. The close relationship between the agricutura1 and geological sciences is not new–crop production depends on the existence and maintenance of fertile soil and agronomists rely on knowledge of mineralogy and geochemist}’ of clays and other soil constituents. In the animal sciences, the addition of crushed limestone to chicken feed to ... Διαβάστε περισσότερα

Dr. Georgian Melinte, Dr. Veselina Georgieva, Dr. Marie-Anne Springuel-Huet, Dr. Andreï Nossov, Prof. Ovidiu Ersen, Dr. Flavien Guenneau, Prof. Antoine Gedeon, Dr. Ana Palčić, Dr. Krassimir N. Bozhilov, Dr. Cuong Pham-Huu, Prof. Shilun Qiu, Dr. Svetlana Mintova, Dr. Valentin Valtchev First published: 27 October 2015Full publication history DOI: 10.1002/chem.201501919View/save citation Abstract The principle aspects and constraints of the dynamics and kinetics of zeolite nucleation in hydrogel systems are analyzed on the basis of a model Na-rich aluminosilicate system. A detailed time-series EMT-type zeolite crystallization study in the model hydrogel system was performed to elucidate the topological and temporal aspects of zeolite nucleation. A comprehensive set of analytical tools and methods was employed to analyze ... Διαβάστε περισσότερα

Η δυνατότητα εφαρμογής του φυσικού ζεόλιθου στην επεξεργασία των απόνερων (The potential application of natural zeolite for greywater treatment) Nurul Widiastutia*, Hongwei Wua,b, Ming Angb, Dong-ke Zhanga aCentre for Fuels and Energy and bDepartment of Chemical Engineering, Curtin University of Technology, GPO Box U1987, WA 6845, Australia Tel. +61 (8) 9266 1139; Fax +61 (8) 9266 1138; email: widiasn@optusnet.com.au Abstract Natural zeolites are good potential material for water and wastewater treatment. It is due to the advantages of low cost, ion-exchange and adsorption capability of the natural zeolites. It can also be modified and regenerated. This paper thus looks at ... Διαβάστε περισσότερα

Φυσικοί ζεόλιθοι στην επεξεργασία του πόσιμου νερού (Natural zeolites in the water treatment process) D. BARLOKOVÁ ABSTRACT In many cases it is necessary to treat water intended for human consumption in order to meet the requirements under the Regulation of the Government of the Slovak Republic No. 354/2006 defining the requirements for water intended for human consumption and monitoring the quality of drinking water. When searching for appropriate water treatment technologies emphasis is placed on the development of new, more efficient and cost-effective technologies and materials. The objective of the study was to compare the removal of dissolved iron and ... Διαβάστε περισσότερα

Mostafa Ragab Abd El Wahab, Moaa Korany Seliem, Essam Abd El Rahman Mohamed, Ali Quarny seliem, Mohamed Gad Shahien Scanning electron micrographs of natural and synthetic zeolites A. ZN (a), ZH (b) and ZF (c). ZN is characterized by the presence of prismatic crystals of phillipsite-K (3a). (ZH) shows particles with irregular morphology associated with well-developed crystals (3b). (ZF) shows well developed cubic crystals with sharp edges and smooth surfaces (3c) Abstract In this study, we prepared hydrated and dehydrated Na-zeolites under different conditions using sodium hydroxide (NaOH) and Egyptian kaolin. The synthetic zeolites were characterized by XRD, SEM, specific ... Διαβάστε περισσότερα