Waste , batch extraction

A test method for the batch extraction of treated or untreated solid waste or sludge, or solidified waste, to provide an indication of the leaching potential (ASTM D-5233) is also available. The goal of this test method is to provide an extract for measurement of the concentration of various analytes and therefore may be applied to a study of the smaller molecules that reside within the coal matrix. This test method, as written, is intended to provide an extract suitable for measurement of the concentration of analytes that will not volatilize under the conditions of the test method and may appear to offer limitations on the use of coal, but the test method does describe a procedure for performing a batch extraction of a solid. Again, the sampling and handling requirements that may be associated with the analysis of coal should also be applied to the method. 

ASTM D-5233. Standard Test Method for Single Batch Extraction Method for Wastes. 

The process sequence now used is shown in Fig. 4. Since only about 5% of the fission products are disposed of in waste solutions from the Tramex batch extraction, that process serves primarily as a feed pretreatment for the LiCl AIX. The Tramex product contains about 98% of the transcurium elements and can be processed quickly to maximize the recovery of 253Es which has a 20-d half-life. As time permits, the "clean rework" can be processed to recover the remaining actinides. 

Fig. 1. Alkalinity release and pH associated with sequential batch extractions of solidified/stabilized hazardous wastes...

We have made equal volume batch extraction measurements on synthetic high sodium concentration waste using 20 volume % DHDECMP in 2 1 decalin-DIPB. Only actinides and a few chemical constituents were examined. Techniques were as described in the above section. Extraction data are shown in Table V. 

A batch process produces 5 t of aqueous waste containing 25% wt acetic acid. The acetic acid is to be recovered by extraction with isopropyl ether. Equilibrium data are given in Table 10.1. 

ESTER A batch process for immobilizing nuclear waste in a borosilicate glass for longterm disposal. Developed in Italy in the 1970s and installed at the Euratom Research Centre, Ispra, in 1981. Intended for use in the radioactive pilot plant (Tmpianto Vetrificatione Eurex, IVEX) at the European Extraction Plant (UREX) at Saluggia, Italy. 

In order to validate the hypothesis mentioned above, the Ni retention capacity of the Lac Tio waste rock was estimated using a batch sorption test performed on a fresh (C1) and weathered (C4) sample, followed by a 3-step Sequential Extraction Procedure (or SEP). The batch sorption test was done using a 10 mg/L Ni solution with an initial pH of 6, an ionic force adjusted to 0.05 M with NaN03 and with a liquid/solid ratio of 25. Some of the batch sorption results are presented in Figure 3. 

In summary, compared with earlier processes which utilize hazardous solvents and generate large waste streams, the carbonylation of chloropinacolone offers an environmentally and operationally advantaged process since it requires (r) very little excess amine or methanol, (fr) no extraneous reaction solvents, Hi) little or no extraction solvent, and (fr) the tributylamine coreactant and methanol components are readily recycled. This was accomplished while also demonstrating similar yields, shorter reaction times, and higher product concentrations which result in a significant reduction in the number of batches and time required to produce significant quantities of methyl pivaloylacetate. 

The zinc-rich electrolyte is now electrowcn for zinc which can amount to as much as 1300 lbs. per 20 ton batch. Six hundred fifty pounds of zinc are extracted from the waste stream while the balance canes from cementation zinc which was added to remove cadmium, tin, and nickel. 

Delmau proposed the combined extraction of cesium and strontium from caustic wastes by adding a crown ether and a carboxylic acid to the CSSX solvent.126 The classical DtBuC18C6 and one carboxylic acid were combined with the components of the CSSX solvent optimized for the extraction of cesium, allowing for the simultaneous extraction of cesium and strontium from alkaline nitrate media simulating alkaline high-level wastes present at the SRS. The promising results of these batch tests showed that the system could reasonably be tested on actual waste. 

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