Acid stripping

The waste streams from the H-Area processes are evaporated, acid-stripped, and adjusted to pH > 13 by addition of NaOH before storage in underground double-shell tanks. 

Electrophoresis on cellulose acetate strips (Sepraphore III, Gelman Instrument, Ann Arbor, MI) was done in the conventional manner [12] in order to obtain a comparative electrophoretic mobility of non-adsorbed albumin. For this purpose, BSA-BSA (2.5 w/v) was deposited on the cellulose acetate paper twice in volumes of 10 ul each. Electrophoresis was attain performed in the Gelman Chamber with Pt electrodes at 20°C (see Table 3) After completion, the strips were stained with Ponceau S protein stain (Gelman Instruments) and washed with 5 acetic acid. The stained cellulose acid strips were subsequently cut into 3 mm wide pieces which were monitored for protein content y-count-ing. 

Stripping the uranium from the solvent can be accomplished by using either acid or alkaline solutions. If an alkali carbonate solution is used, the stripped solvent then requires equilibrating with sulfuric acid before recycling to the extraction stage. Sulfuric acid stripping obviates the need for such equilibration. 

The rate of extraction of the lanthanides by the 2-ethylhexyl ester of 2-ethylhexylphosphonic acid (e.g., PC88A, P507) is slower than for DEHPA but the higher distribution coefficients allow extraction from more dilute solutions. Also, as acidic stripping is easier than with DEHPA, the reagent has been used commercially to separate lutetium from terbium and ytterbium. 

Stripping Acidic stripping Alkaline stripping U02(HDEHP... 

As with any other analytical method, MCA s capacity is enhanced if it is easy to remove interfering compounds. Microbial adaptation confers specificity in binding unwanted compounds so they can be swept out without losing the sample for analysis. Figures 5a and 5b show the data for phenol and vanillic acid stripping under convenient conditions, namely, with easily acquired amounts of stripper cells (5 x 1010 cells), and conditions where interfering compound concentrations are relatively large, i.e., up to 10 times the amount of sample for analysis. 

The mechanism of transport of GPG using SLM has been studied at the authors laboratory [56]. GPG could be permeated from alkaUne feed of carbonate buffer into an acidic stripping solution of acetate buffer across the membrane comprising Aliquat-336 in -butyl acetate immobiUzed in a polypropylene (Gelgard 2400) support. The transport mechanism is a case of counter transport exhibiting overall rate dependence on solute diffusion in the membrane phase as well as the mass transfer across the aqueous boundary films. 

Another process involves the use of an organic solvent to extract the borax brines. Boric acid is extracted with kerosene, carrying a chelating agent. In a second mixer-settler system, dilute sulfuric acid strips the borates from the chelate. The aqueous phase with boric acid, potassium sulfate, and sodium sulfate is purified by carbon treatment and evaporated in two evaporator-crystallizers. From the first, pure boric acid is separated, and from the other, a mixture of sodium and potassium sulfates. 

Hypoxanthine (2 g) in trifluoroacetic acid (40 ml) was stirred and hydrogenated (100 bar/35°C/21 hr) over platinum oxide (0.1 g).31 The catalyst was filtered and the trifluoroacetic acid stripped under vacuum. The product was shown (potentiometric titration) to contain 1.9 moles of TFA. 

Americium Feed Adjustment. The aqueous americium-bearing, sodium nitrate/sulfate-nitric acid solution was evaporated and acid-stripped. Oxalic acid was added to complex iron and plutonium ions before feeding to a cation exchange column. 

The method of separation results in the Am being diverted to the aqueous waste stream of the second plutonium solvent extraction cycle (2 AW). The calculated predicted volume of this stream for the full campaign was 2.2 x 10 L. Physical limitations of equipment required that the solution be evaporated in two steps instead of one. The first step could result in a concentration factor of 25 to 50. The second step included nitric acid stripping and evaporation to the final volume. 

Sodium americyl sulfate is also relatively insoluble in nitric acid (Table I). The solubility of this salt is also exceeded during the first stage of evaporation. However, subsequent acid stripping of the solutions reduces the nitric acid concentration and the salts redissolve. 

The aqueous waste stream (2AW) containing the 241 was concentrated and stripped of acid using two batch evaporators in the Low Activity Waste (LAW) system. The first concentration step was performed in the LAW batch evaporator. Acid stripping with water and additional evaporation was performed in the second LAW batch evaporator. The average concentration of the Am entering this two-step evaporation process was 3.4 x 10 g/L after the first step, the Am concentration was 0.08 to 0.15 g/L after the second step, the Am concentration was 0.2 to 0.3 g/L, and the nitric acid concentration was 2.0 to 2.5M. 

Synthesis, which takes place in a reactor with an internal lining of corrosioa-resstaiif bricks, and whose dimensions, for a unit production capacity of 70,000 t/year, are 2.6 to 2.7 m in diameter and 12 m high, for a ma.ximum size of about 150,000 t/year. Hydrochloric acid stripping in the vapor phase requires the use of hastelloy B for the parts of the equipment in contact with this acid. 

Effect of temperature on fatty acid stripping of soybean oil... 

After scrubbing, the coextracted actinides and lanthanides are removed from the organic phase by two separate strip columns (a reductant and dilute nitric acid strip, followed by a dilute oxalic acid strip). After destruction of the excess oxalic acid, the two strips are combined with other recycle streams that are... 

For PT extraction of 3-MH and 3-MHA, the sample pH is adjusted to 7.0 to reduce the free fatty acids stripping and to avoid 3-MHA hydrolysis. The optimized PT conditions are reported in Table 5.7 (Versini et al., 2008). 

There are three types of deodorization operations. The batch process is the least common, due to its low efficiency and inconsistent product quality. Semi-continuous and continuous deodorizers have improved processing efficiency. There are several configurations of the continuous deodorizer, including singleshell cylindrical vessel type, vertically stacked tray type, and the thin-film packed column type. This last provides excellent fatty acid stripping with minimum use of steam, but it achieves neither desired heat bleaching nor effective deodorization due to the relatively short retention time. A retention vessel has to be used after the column distillation (De Greyt and Kellens 2000). 

In the uranium stripping contactor, uranyl nitrate was transferred back to the aqueous phase by 0.1 M nitric acid strip solution. Fission products were separated from the impure uranyl nitrate by additional cycles of solvent extraction and by adsorption on silica gel, not shown. 

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