Batch solvent

We are not aware of any previous studies of the removal of plutonium or americium from (NH )2ZrF6-NHltF-NH N03 solutions. For ready plant-scale application, precipitation, sorption on inorganic materials, or batch solvent extraction processes may all be satisfactory. An inexpensive inorganic material with great selectivity and capacity for sorbing actinides, and with suitable hydraulic properties, would be especially attractive. 

Entry Batch Solvent Process Isol. Purity Remarks... 

Solvent extraction of benzene works the same way. But instead of water, the various solvents used are sulfolane, liquid SO2, diethylene-glycol, and NMP (N-methyl pyrrolidone). The paint thinner/salt/water process described above might be called a batch solvent process, since it consists of sequential steps that can be repeated, batch after batch. Some low-volume commercial processes still operate that way. 

The Extraksol process is a batch, solvent extraction technology that extracts organic contaminants from unconsolidated solids. The Extraksol system is mobile, offering flexibility in treating soils and sludges to different decontamination levels. 

Data may be obtained from a large number of batch solvent extractions and binodal eurves may be plotted on triangular diagrams as described earlier in this paper. Such information will permit calculations of the number of stages and solvent requirements. Considerable specialized equipment and care are necessary to obtain reliable data of this nature. 

Batch solvent extraction methods (e.g., by separatory funnel) for the preparation of extracts for biological analysis have a number of major problems. A large volume of solvent must be evaporated after the extraction step in order to obtain a sample sufficiently concentrated to be useful for biological testing. Artifacts can occur from solvent impurities, and reactions can occur during the evaporation process. 

Equipment and consumables of different ages Columns from different suppliers or different batches Solvents, reagents, and other materials with different quality... 

Campaign Mode Operation with Batch Solvent Feeding... 

A typical composition of feed solution and the fractional distribution of the feed solution components into the various exit streams are shown in Table I. The feed solution is usually the product of a Cleanex batch solvent extraction ( T0), a process... 

In 1855, Deiss of Marseilles, France, was first to employ solvent extraction (1). He used carbon disulfide to dissolve olive oil retained in spent olive cakes. This technology used batch solvent extraction, where the material was held in a common kettle for both the extraction process as well as the subsequent meal desolventizing process. Deiss obtained a patent for batch solvent extraction of olive oil in 1856 (1). Small batch solvent extraction plants were installed in France and Italy, and by 1870, small batch solvent extraction facilities had spread across Europe. Larger scale solvent extraction plants were supplied by Rose, Downs, and Thompson (2) of Hull, England, starting in 1898. 

Reproducibility, as defined by ICH, represents the precision obtained between laboratories with the objective of verifying if the method will provide the same results in different laboratories. The reproducibility of an analytical method is determined by analyzing aliquots from homogeneous lots in different laboratories with different analysts, and by using operational and environmental conditions that may differ from, but are still within the specified, parameters of the method (interlaboratory tests). Various parameters affect reproducibility. These include differences in room environment (temperature and humidity), operators with different experience, equipment with different characteristics (e.g., delay volume of an HPLC system), variations in material and instrument conditions (e.g., in HPLC), mobile phases composition, pH, flow rate of mobile phase, columns from different suppliers or different batches, solvents, reagents, and other material with different quality. 

The focus of this chapter will be the chemistry of solvent extraction and its use as a separation process, particularly altering the chemical parameters of an extraction system in order to bring about the desired separation in a single step. The following two chapters will describe in more detail the principles and applications of chromatographic processes (in which a large number of equilibrium steps occur), in contrast to the batch solvent extraction processes. 

The choice of process depends, as stated, on the type of raw material but also on the desired plant capacity. Continuous solvent extraction plants are supplied for daily seed throughput of 100 to 3000 tonnes. The first three processes listed and batch solvent extraction can be used for less than 100 tonnes per day. 

Essential oils are extracted in several ways with fat, by distillation, and by batch solvent extraction. The oldest method, used today only for extremely valuable essential oils, is enfleurage-defleurage. This consists of layering blossoms of the material to be extracted between fat-coated glass plates and allowing the essential oil to perfuse into the fat. The blossoms are renewed daily. At the end of the season, the fat is scraped from the plates, melted, poured into containers, and sold as pomade, or is batch-extracted with cold ethanol and sold as extraits. Another technique consists... 

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