摘要:

An operational definition of recovery from dilute solutions is proposed, the major characteristic costs of such recovery processes are identified, and promising strategies for improving equipment and process performance are suggested.

ISSN:0149-6395    

DOI:10.1080/01496398708068947

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A principal purpose of this paper is to call out what is perceived to be a timely need for increased research to develop improved and new solvent extraction technology for recovery of137Cs and90Sr from strong (≥ 0.5MHNO3) acid media, technology which can be quickly scaled up to routine plant-scale operation with highly radioactive waste solutions when needed.

ISSN:0149-6395    

DOI:10.1080/01496398708068948

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The recovery of copper from dilute sulfuric acid leach solutions has been a commercial reality since 1968 (1), and since then the technology has gained worldwide acceptance. Only one chelating functionality, the hydroxy oxime group, has been used commercially for this task. There are, however, two distinct classes of extractants based on the hydroxy oxime group: the salicylaldoximes, which are very strong copper extractants and the ketoximes, which are mo derate copper extractants. A third class of extractants combines a ketoxime with a salicylaldoxime in about a 1/1 mole ratio and results in some surprising advantages. This paper will discuss each reagent class, showing their advantages and disadvantages and will also introduce two new reagents, LIX¯ 84 and LIX 984, showing their behavior with respect to copper extraction, and discussing where they may be used to advantage.

ISSN:0149-6395    

DOI:10.1080/01496398708068949

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The measurement of individual rate constants, as well as the quantitative determination of the contribution of the liquid-liquid interface to the overall extraction kinetics in a well known extraction system, nickel extraction by oxine and its high molecular weight analog (KELEX 100), has revealed that a three path extraction mechanism is operative. The-results indicate that the interfacial region provides a more conducive reaction medium in comparison to the bulk aqueous phase. The finding of concurrent bulk and interfacial mechanisms not only reveals the complexity that can be involved in this extraction system, but also enables one to design more efficient separation techniques based on these differences in mechanisms.

ISSN:0149-6395    

DOI:10.1080/01496398708068950

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A robust differential homotopy procedure is developed that is suitable for solving the bordered block tridiagonal systems of nonlinear equations that result from liquid-liquid extraction models. The procedure is capable of readily utilizing newton, fixed-point, and custom homotopy mapping. It is shown to have an efficiency far superior to Kubicek's method and comparable to that of Rheinboldt. Application of the method to liquid-liquid extraction cascade models revealed that the newton homotopy would converge to a solution as rapidly as a simultaneous correction procedure and that use of a custom homotopy resulted in faster convercrence.

ISSN:0149-6395    

DOI:10.1080/01496398708068951

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A radiotracer method for the measurement of the mass holdup of a solute being processed in a counter-current pulse column using the average residence time distribution is presented and investigated by mathematical modelling. Typical solutions to the model for impulse tracer injections of the solute at the inlet show that while the number and volume of stages have a significant effect on the response of the system, the amount of backmixing has little effect, particularly for small systems. The system response to impulse tracer injections under various conditions was simulated with this model and model parameters were extracted from these simulated results by using a nonlinear least squares method to demonstrate the approach.

ISSN:0149-6395    

DOI:10.1080/01496398708068952

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Experimental investigations of packing performance in extraction service were conducted in a 10.2 cm. diameter column. Both random and structured packing elements were covered in separate studies. Test systems were toluene/acetone/water and n-butanol/succinic acid/water. Measurements were made of dispersed phase holdup and mass transfer rate. A tentative correlation was developed, based on a modification of basic tests using an empty column, involving an effective drop diameter.

ISSN:0149-6395    

DOI:10.1080/01496398708068953

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Trioctyl phosphine oxide (TOPO) is useful for the extraction of many inorganic and organic compounds. A mixed trialkyl phosphine oxide (TRPO)

ISSN:0149-6395    

DOI:10.1080/01496398708068954

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

This paper presents a process for treatment of an AgNO3electrolyte. Ag/Cu separation is done with conventional solvent extraction (SX). Cathode copper is electroworf in a diaphragm electrolysis cell while silver scrap is simultaneously dissolved anodically. The process proves to be a very effective recycling technique and is now being investigated on a pilot scale.

ISSN:0149-6395    

DOI:10.1080/01496398708068955

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Solvent from the Idaho Chemical Processing Plant (ICPP) (operated by Westinghouse Idaho Nuclear Company, Inc.) has been tested to determine the ability of activated alumina to remove secondary degradation products—those degradation products which are not removed by scrubbing with sodium carbonate.

ISSN:0149-6395    

DOI:10.1080/01496398708068956

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor