Phillip C. Wankat

Bio: Phillip C. Wankat is an academic researcher. The author has an hindex of 1, co-authored 1 publications receiving 14 citations.

Micelles in Separations: Practical and Theoretical Review

Abstract: (1985). Micelles in Separations: Practical and Theoretical Review. Separation and Purification Methods: Vol. 14, No. 2, pp. 213-304.

Gas Purification by Pressure Swing Adsorption

Abstract: (1985) Gas Purification by Pressure Swing Adsorption Separation and Purification Methods: Vol 14, No 2, pp 157-212

Parametric Ion-Exchange Processes (Parametric Pumping and Allied Techniques)

Abstract: The term “parametric pumping” implies the idea of pumping, that is of transport of material (in our case, ionic species) up along some potential scale (in our case, chemical potential), at the cost of degradation of some flux of energy (to be specified later). The term “parametric” refers to the fact that the energy flux just mentionned is obtained by modulating some intensive thermodynamic parameter such as temperature, pressure, ionic strength, pH, electric potential, … Typical examples are temperature-swing ion-exchange and pressure-swing adsorption. The concept of parametric pumping is due to Wilhelm and coworkers (1966, 1968). Their original results deal with adsorption from the liquid phase, modulated by temperature. Let us examine how these phenomena are implemented.

Dual-temperature ion exchange fractionation

Abstract: This paper reviews the results obtained by studying the dual-temperature ion-exchange fractionation (DTIXF) technique. The DTIXF is based on the use of different affinity at different temperatures of ion exchangers towards ions to be separated. This technique allows to design absolutely reagentless and, as a result, wasteless fractionation technology. The review considers the temperature dependencies of selectivity of commercially available ion-exchange (LX) resins towards components of ionic mixtures of different complexity starting from binary model systems up to naturally existing nonacomponent effluents. A novel approach for predicting the temperature sensitivity of a given LX system is presented and discussed. The same approach has been shown to be applicable for the design of IX resins with temperature-dependent selectivity. The paper also reports the results obtained in the practical application of DTIXF technique for concentration of magnesium from seawater and copper from acidic mine wat...

Waste recycle pressure swing adsorption to enrich oxygen from air

Abstract: Pressure swing adsorption is a method for separating gases by selective adsorption. It is being used increasingly in industry where for some applications, including air separation, the number of plants have increased at a near exponential rate in recent years. However, despite the many hundred different plant configurations and cycles, there is still a lack of understanding of the basic process steps and plenty of scope for achieving even better plant performances. This study examines experimentally and theoretically a two bed process for separating oxygen from air using a zeolite adsorbent. A plant was designed and built to incorporate the novel feature of recycling waste gas from the purge and depressurization steps back into the feed line and also to investigate conventional purge, backfill and combined cycles. Theoretical modelling had predicted that large amounts of waste gas could be recycled without loss in product oxygen concentration, but causing an improvement in oxygen yield. This was verified experimentally, demontrating potential energy savings. For each cycle investigated the product oxygen concentration and yield were optimized over a range of product amounts per cycle while continually monitoring the main process variables. Other experimental work included studies of the bed temperature and pressure profiles, the waste gas oxygen concentrations, unsymmetrical operation and supplying purge from different sources. The theoretical aims were to further develop the instantaneous local equilibrium (ILE) model used by Kirkby (1984). The model was made more efficient and developed to include novel options for waste recycling and the previously neglected, but common, design feature of supplying purge directly from one bed to another. The model's qualitative agreement with experiments was verified over a wider range of cycles and the quantitative agreement was improved for some cycles.