Resins removal

Amount of Cs, solution phase Thus, at equilibrium the 1.0 g of resin removed is ... 

Weak and strong acid-type resins are for removal of cations and are called cation exchangers. Weak and strong base resins remove anions and are called anion exchangers. In addition to these four resin types, there are specialty resins used in appHcations where higher specificity for certain ions under challenging conditions is a critical factor. 

In Canada, ion-exchange (qv) technology has been used to produce potassium sulfate (4). Ion-exchange resins remove sulfate ions from lake water containing sodium sulfate. This is followed by a wash with aqueous solutions prepared from lower grade muriate of potash. High purity potassium sulfate is collected from the crystallizers into which the wash mns. 

Ligand exchange Equihbrium Chromatographic separation of glucose-fructose mixtures with Ca-form resins Removal of hea y metals with chelating resins Affinity chromatography... 

Provision of adequate washing facilities including resin-removal cream enforce high standards of personal hygiene. 

Figure 14.23 Photographs of cross-sectional views of resin removed from a Maddock solidification experiment for a Stratablend screw. The labels are the axial positions of the views in diameters...

The combinatorial library synthesis of a diverse set of trisubstituted ureas has been described [64]. The synthetic pathway involves the prehminary preparation of various nitrophenylcarbamates from commercially available nitrophenyl chlorofor-mate and a selection of amines allowing for wide scope in the divergence of the final urea products. In a further reaction of the nitrophenylcarbamates with a second amine, the urea was generated. Simultaneous addition of an electrophilic and basic scavenger resin removed all by-products, again allowing rapid isolation of the products in excellent yield and purity (Scheme 2.43). 

Once all the metal has been dissolved, the solution is passed through a cation exchange column (AG 50W-X8, 100-200 mesh BioRad Laboratories). A bed volume of as little as 40 ml has been used successfully in this work. The resin removes the cations present from the large quantity of molybdate and any other anions that might be present. The column is now converted to the ammonium form by passing 0.5 M NH Cl through the column until the pH of the... 

Cleavage from the resin (with the retention of tBu-type side chain protection) The resin (1 g) was shaken for 30 min with a mixture of AcOH, TFE, and CH2C12 (1 1 3,20 mL) and the resin removed by filtration. The procedure was repeated once more and the resin washed with the above mixture (3x5 mL) the combined filtrates were taken to dryness in vacuo after addition of toluene (20 mL). The crude product was purified by HPLC. 

Fruit juices can be deacidified with a weak base anion-exchange resin. Removal of compounds which cause a bitter taste is a more popular application (26,27). It is accomplished with resins that have no ion-exchange fimctionality. In essence, they are similar to the copolymer intermediates used by resin manufacturers in the production of macroporous cation and anion exchangers. These products are called polymeric adsorbents. They are excellent for removal of limonin [1180-71-8] and naringin [1023647-2], the principal compounds responsible for bitterness in orange, lemon, and grapefruit juices. The adsorbents are regenerated with steam or alcohol. Decaffeination of coffee (qv) and tea (qv) is practiced with the same polymeric adsorbents (28). 

Table XVII is an example of the test result showing comparable efficiency of SAE, PAE and alkylphenol ethoxylates in resin removal from sulfite pulp. A Japanese patent specification(24) by Lion Fats and Oils describes 10-16 mole ethoxylates of secondary alcohols as extremely useful in deresination of pulp, especially in the manufacture of dissolved pulp for the rayon industry. According to the patent specification, to alkyls give the best results among 12 mole ethoxylates ethoxylates of from 10 to 13 moles of EO can give the best results among other ethoxylates of C secondary alcohols, and the optimum amount of SAE(12E0) is in the range between 0.2 and 0.6% by weight based on pulp.

Deionize 100 ml formamide with 5g Amberlite MB1 resin. Remove resin by filtration. Add 0.03 g xylene cyanol FF, 0.03 g bromophenoi blue and Na2EDTA to 20 mM. Store at room temperature. 

Backwashing Backwashing the resin removes suspended solids and resin fines that may have collected in the vessel. Typical flow rates for backwashing range from about 4 to 8 gpm/ft2 for a minimum of 10 minutes or until the backwash water runs clear. The target is to expand the bed by 50% for adequate backwash. Backwash water is usually sent to drain. 

Caution If the rosin crystallizes, thus making it difficult to obtain the correct softening point, prepare a new sample by heating the rosin rapidly, yet cautiously, over a flame to a temperature of 160° to 170° to destroy all crystal nuclei. Dip the thermometer bulb into the molten resin, remove it momentarily, and rotate the thermometer to provide a uniform resin film on the bulb as it partially cools in the air. Dip the bulb in the melted... 

Titanium(iv) benzylidenes (Schlock carbenes) 4 react with resin-bound esters 5 to generate the resin-bound enol ethers 6. Treatment of the enol ethers with a mixture of trifiuoroacetic acid (TEA) and trifluoroacetic anhydride (TFAA) leads to cleavage from the resin, removal of the Bu Me2Si group, and subsequent cyclization to give the benzothiophenes 7 (Scheme 2) <2004JOC6145>. 

Ion exchange (water softening) the process in which an ion-exchange resin removes unwanted ions (for example, Ca2+ and Mg2+) and replaces them with Na+ ions, which do not interfere with soap and detergent action. (18.4)... 

On-Resin Removal of 5-(Acetamidomethyl) with Mercniy(II) Acetate General Procednre - ... 

Pass the CuSOr/KjCr Or solution, which is greenish yellow in colour, through the resins at a flow rate of, 50inl/I5 minutes. The SAC resin removes the potassium and copper, and a green band will form on it du to the copfier. I he eluate from the S.-VC column, containing sulfuric and chromic acids, is decolorized bv the. SB. column.. n orange band is formed on the SB. resin due to the chromate. 

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