Download or read book Ion Exchange Kinetics of Cesium for Various Reaction Designs Using Crystalline Silicotitanate UOP IONSIV IE 911 written by Sung Hyun Kim and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Through collaborative efforts at Texas A & M University and Sandia National Laboratories, a crystalline silicotitanate (CST), which shows extremely high selectivity for radioactive cesium removal in highly concentrated sodium solutions, was synthesized. The effect of hydrogen peroxide on a CST under cesium ion exchange conditions has been investigated. The experimental results with hydrogen peroxide showed that the distribution coefficient of cesium decreased and the tetragonal phase, the major component of CST, slowly dissolved at hydrogen peroxide concentrations greater than 1 M.A simple and novel experimental apparatus for a single-layer ion exchange column was developed to generate experimental data for estimation of the intraparticle effective diffusivity. A mathematical model is presented for estimation of effective diffusivities for a single-layer column of CST granules. The intraparticle effective diffusivity for Cs was estimated as a parameter in the analytical solution. By using the least square method, the effective diffusivities of 1.56 ł 0.14 x 10-11 m2/s and 0.68 ł 0.09x 10-11 m2/s, respectively, were obtained. The difference in the two values was due to the different viscosities of the solutions. A good fit of the experimental data was obtained which supports the use of the homogeneous model for this system. A counter-current ion exchange (CCIX) process was designed to treat nuclear waste at the Savannah River Site. A numerical method based on the orthogonal collocation method was used to simulate the concentration profile of cesium in the CCIX loaded with CST granules. To maximize cesium loading onto the CST and minimize the volume of CST, two design cases of a moving bed, where the fresh CST is pulsed into the column at certain periods or at certain concentration of cesium, were investigated. Simulation results showed that cesium removal behavior in the pilot-scale test of CCIX experiment, where the column length is 22 ft and the CST is pulsed 1 ft in every 24 hours, was well predicted by using the values of the effective diffusivities of 1.0 to 6.0 x 10-11 m2/s.

Download or read book The Effect of Pressure and Organic Constituents on the Cesium Ion Exchange Performance of IONSIV IE 911 written by and published by . This book was released on 2000 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study examined cesium (137Cs) ion exchange of crystalline silicotitanate (CST) in simulated waste solution. In particular, the study focused on the effect of CST pretreatment on the kinetics and extent of cesium adsorption. The test used IONSIV{reg_sign}IE-911 (UOP LLC, Molecular Sieves Division, Des Plaines, IL), the engineered form of CST. Pretreatment steps examined include: soaking CST in 2M NaOH solution for three days, exposing CST to 50% relative humidity for one week, flowing organic-containing (saturated) salt solution through a CST packed bed (at 5 cm/min. superficial velocity), or drying CST in air at 100 C for three days. Some tests occurred under 50 and 25 psig of argon. The following conclusions summarize the results. Pretreatment of IE-911 in organic-containing (e.g., tri-n-butyl phosphate, dibutylphosphate, butanol, paraffin and Dow Corning H-10 defoamer) simulated waste or simulated waste yielded a 83% slower rate of cesium adsorption and 56% lower cesium capacity after one week. Pretreatment of IE-911 in 2M caustic solution for 48 hours yielded a slower approach to equilibrium cesium distribution in batch contact tests--7.7 mL/(g*h) during the first 48 hours and 2.4 ml/(g*h) thereafter. Carboxylates and adsorbed carbonates inside the pores likely affect the cesium transport by either increasing the path-length or reducing mass transfer rate. Heating IE-911 as received from the vendor at 100 C for 24 hours significantly degraded its cesium removal performance by a 40.7% reduction in capacity and 43% reduction in sorption rate over one week of testing. Testing determined nearly identical distribution coefficients K{sub d} between lot {number_sign} 9990-9681-0004 and 9990-9881-0005 (i.e., difference of only 5.6%). Tests measuring water insertion rates into IE-911 show that hydration of the IE-911 does not appear to limit the rate of cesium sorption. Increasing the atmospheric pressure from 0 to 50 psig had no effect on cesium sorption. Note that lower apparent capacity or slower cesium sorption rate in these limited-duration batch contact tests as a result of pretreatment do not necessarily imply reduced dynamic performance in a flowing ion-exchange application. The experiments that provided the bases for the currently proposed facility design used caustic-pretreated IE-911. Another report will assess whether the presence of the organic compounds in the waste solution impeded column performance.

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2004 with total page 768 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ion Exchange Kinetics of Cs SrOH and Rb for the Hydrous Crystalline Silico titanates UOP IONSIVtm IE910 and UOP IONSIVtm IE911 written by Michael E. Huckman and published by . This book was released on 1999 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reactions of Trace Amounts of Cesium with Ion Exchange Resins written by H. S. Miller and published by . This book was released on 1951 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Register der grondboringen gedaan langs den IJsseldam en den Lekdijk benedendams in Juli en Aug 1874 written by and published by . This book was released on 1874 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Kinetic Model for Ion Exchange Between Cesium and Sodium Using Silico titanates written by Luan Thanh Nguyen and published by . This book was released on 1994 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ion Exchange of Cesium by Crystalline Silico titanates written by and published by . This book was released on 1995 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: The crystalline silico-titanates developed by the Department of Chemical Engineering at Texas A & M University, Sandia National Laboratories and UOP exhibits extremely high ion exchange selectivity for removing cesium from aqueous defense wastes. Based on experimental data and structure studies, a competitive ion exchange model was proposed to predict the ion exchange performance in different simulated waste solutions. The predicted distribution coefficients were within 10% of the experimentally determined values.

Download or read book Ion Exchange Performance of Commercial Crystalline Silicotitanates for Cesium Removal written by and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Kinetics of Reactions in Ionic Systems written by T. J. Gray and published by Springer. This book was released on 2013-12-14 with total page 581 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ion Exchange of Cesium by Crystalline Silico titanates written by Zhixin Zheng and published by . This book was released on 1995 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cesium Ion Exchange Using Actual Waste written by and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Directory of Graduate Research written by and published by . This book was released on 2001 with total page 1846 pages. Available in PDF, EPUB and Kindle. Book excerpt: Faculties, publications and doctoral theses in departments or divisions of chemistry, chemical engineering, biochemistry and pharmaceutical and/or medicinal chemistry at universities in the United States and Canada.

Download or read book Ion Exchange Recovery of Cesium from Alkaline Supernatant Waste written by R. P. Popovich and published by . This book was released on 1964 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ion Exchange Equilibrium Constants written by Y. Marcus and published by Elsevier. This book was released on 2013-10-22 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ion Exchange Equilibrium Constants focuses on the test-compilation of equilibrium constants for ion exchange reactions. The book first underscores the scope of the compilation, equilibrium constants, symbols used, and arrangement of the table. The manuscript then presents the table of equilibrium constants, including polystyrene sulfonate cation exchanger, polyacrylate cation exchanger, polymethacrylate cation exchanger, polysterene phosphate cation exchanger, and zirconium phosphate cation exchanger. The text highlights zirconium oxide anion exchanger, zeolite type 13Y cation exchanger, and zeolite type 4A cation exchanger. The book also presents references for mineral exhangers and polymeric ion exchangers. The book is a valuable reference for readers interested in equilibrium constants.

Download or read book Electrically Switched Cesium Ion Exchange written by Michael A. Lilga and published by . This book was released on 1997 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Preliminiary Flowsheet Ion Exchange Process for the Separation of Cesium from Hanford Tank Waste Using Duolite tm CS 100 Resin written by and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: