907 resultados para ION EXCHANGE MATERIALS
Resumo:
"Date Declassified: September 23, 1955."
Resumo:
"Date Declassified: September 23, 1955."
Resumo:
"Contract AT(49-1)-535."
Resumo:
The investigation of the electrolytic precipitation of uranium from a sample of acid leach liquor in an ion exchange membrane cell has been conducted on leach liquor from the Vitro Co. This leach liquor can be treated by the above means to precipitate essentially all the uranium and simultaneously to produce additional acid which may be used for further leaching.
Resumo:
Electrolytic precipitation of uranium from ion-exchange resin eluates has been investigated in a three-compartment cell. A relatively low-energy consumption is required and anodic attack is reduced to a negligible quantity. During the precipitation, acid is produced in sufficient quantity for use as eluant for subsequent eluting operations. The recovered uranium is in the form of a rapid settling, fast filtering precipitate which is easily washed with water to reduce the chloride content to a tolerable concentration.
Resumo:
"Date Declassified: September 23, 1955."
Resumo:
"Date Declassified: September 23, 1955."
Resumo:
"Date Declassified: September 23, 1955."
Resumo:
"Date Declassified: September 23, 1955."
Resumo:
"Contract No. AT(49-1)-621."
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The purpose of this research is to investigate potential methods to produce an ion-exchange membrane that can be integrated directly into a polydimethylsiloxane Lab-on-a-Chip or Micro-Total-Analysis-System. The majority of microfluidic membranes are based on creating microporous structures, because it allows flexibility in the choice of material such that it can match the material of the microfluidic chip. This cohesion between the material of the microfluidic chip and membrane is an important feature to prevent bonding difficulties which can lead to leaking and other practical problems. However, of the materials commonly used to manufacture microfluidic chips, there are none that provide the ion-exchange capability. The DuPont product Nafion{TM} is chosen as the ion-exchange membrane, a copolymer with high conductivity and selectivity to cations and suitable for many applications such as electrolysis of water and the chlor-alkali process. The use of such an ion-exchange membrane in microfluidics could have multiple advantages, but there is no reversible/irreversible bonding that occurs between PDMS and Nafion{TM}. In this project multiple methods of physical entrapment of the ion-exchange material inside a film of PDMS are attempted. Through the use of the inherent properties of PDMS, very inexpensive sugar granulate can be used to make an inexpensive membrane mould which does not interfere with the PDMS crosslinking process. After dissolving away this sacrificial mould material, Nafion{TM} is solidified in the irregular granulate holes. Nafion{TM} in this membrane is confined in the irregular shape of the PDMS openings. The outer structure of the membrane is all PDMS and can be attached easily and securely to any PDMS-based microfluidic device through reversible or irreversible PDMS/PDMS bonding. Through impedance measurement, the effectiveness of these integrated membranes are compared against plain Nafion{TM} films in simple sodium chloride solutions.
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This paper reports a study of ion exchange (IX) as an alternative CSG water treatment to the widely used reverse osmosis (RO) desalination process. An IX pilot plant facility has been constructed and operated using both synthetic and real CSG water samples. Application of appropriate synthetic resin technology has proved the effectiveness of IX processes.
Resumo:
This paper relates to the importance of impact of the chosen bottle-point method when conducting ion exchange equilibria experiments. As an illustration, potassium ion exchange with strong acid cation resin was investigated due to its relevance to the treatment of various industrial effluents and groundwater. The “constant mass” bottle-point method was shown to be problematic in that depending upon the resin mass used the equilibrium isotherm profiles were different. Indeed, application of common equilibrium isotherm models revealed that the optimal fit could be with either the Freundlich or Temkin equations, depending upon the conditions employed. It could be inferred that the resin surface was heterogeneous in character, but precise conclusions regarding the variation in the heat of sorption were not possible. Estimation of the maximum potassium loading was also inconsistent when employing the “constant mass” method. The “constant concentration” bottle-point method illustrated that the Freundlich model was a good representation of the exchange process. The isotherms recorded were relatively consistent when compared to the “constant mass” approach. Unification of all the equilibrium isotherm data acquired was achieved by use of the Langmuir Vageler expression. The maximum loading of potassium ions was predicted to be at least 116.5 g/kg resin.