Ion exchange removal

Researchers concluded that ion exchange removal of nitrate was cost prohibitive at the Livermore site because of the high cost of waste disposal. The perchlorate-only alternative with nitrate removal using another technology was the most cost-effective solution. Perchlorate disposal costs under this option were 350/year, and minimal maintenance of the treatment unit would be required (D20493D, p. 12). The cost estimates are summarized in Table 1. 

Ammonia or amines used for pH control affect the conductivity. To obtain an accurate indication of solids, a cation ion exchanger removes the volatile alkalizers and converts the salts to their corresponding acids. Seven micromhos arc equivalent to 1 ppm concentration for most salts. 

We have previously described ammonia removal with zeolites. However, the development of new methods capable of effective and total ammonia removal from wastewater are extremely attractive in this regard, the ion-exchange removal of ammonia with a Dowex HCR-S ion-exchange resin has been carried out [79],... 

Figure 3. Ion exchange removal of cesium from waste...

Basic ion exchangers remove anions and are regenerated with sodium hydroxide, e.g. 

L-Methionine has been prepared from fV-acetyl-D, L-me-thionine by deacylation with an aminoacylase.37 The lipase was supported on an ion-exchange resin. The reaction was driven to completion by chromatographic ion-exchange removal of the by-product acetic acid and unreacted substrate, the racemic mixture being fed in pulses to the column. The cross-linked enzyme crystals marketed by Altus Biologies are very useful in enzymatic resolutions, because of their enhanced stability to heat and organic solvents and because they can be reused many times. (For more detail on enantiospecific reactions with enzymes, see Chap. 9.)... 

The calcium may be removed from sea water by chemical methods which leave relatively intact the nontroublesome magnesium content (5). An ion exchange removal of the calcium can use the evaporator blowdown brine as a regenerant, if there is sufficient difference in selectivity between the resin and the solution at the concentrations of the incoming feed water and outgoing brine solution. 

O. F. Kamson and A. Townshend, Ion Exchange Removal of Some Interferences on the Determination of Calcium by Flow Injection Analysis and Atomic Absorption Spectrometry. Anal. Chim. Acta, 155 (1983) 253. 

CO2 diffuses through the PTFE membrane (F) and dissolves in the pure water layer (D). At the rear of the water layer is a water porous spacer screen (C) which supports a mixed bed ion-exchanger (A). The ion-exchanger removes ions produced by the continuous dissolution of CO2 and a steady state concentration gradient of CO2 is established as a result of these two processes. The sensor is mounted in a pyrex tube (B) and the... 

The primary functions of builders in laundry detergent formulations is to remove hardness ions to protect the surfactant. Calcium and magnesium ions in wash water can react with surfactants to form insoluble or nonfunctional complexes. Builders reduce water hardness by three main mechanisms. Sequestration forms a soluble complex between builder and hardness ions. Precipitation forms an insoluble complex with hardness ions. Ion exchange removes calcium and magnesium ions by replacing them with soluble sodium ions. 

Ion exchangers Ion exchangers remove both sorts of hardness... 

Explain how the experiment above shows that a the tapwater contains both types of hardness b most of the hardness in it is permanent c the ion exchanger removes hardness just as effectively as distillation does. 

The polishers operate as filters to remove the oxide of metals and undissolved solids from the condensate. As iron oxide is particulate matter, it can be removed by filtration. The filter is a mixed cation and anion exchange resin. The filter removes the insoluble particles and ion exchange removes the dissolved contaminants against the formation of calcium scale while at the same time avoiding the formation of harmful free caustic in water. 

Ion exchange is the reversible exchange of ions between a liquid and a solid in which there is no substantial change in the solid. Ion exchange removal of a ical heat-stable salt anion, Ct, from an amine by an anion exchange resin is illustrated in the following equation where parentheses denote ions bound to the ion exchange resin ... 

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