Diluents aliphatic

Increase the solubility of the nitrogen-donor ligands in aliphatic diluents... 

Some of the modifiers in this study (1-5) were also evaluated in the isoparaffinic diluent Isopar L for cesium extraction performance from a Savannah River waste simulant. The effect the modifiers have on the cesium distribution ratio in aliphatic diluents is more pronounced than it is in polar diluents, such as 1,2-DCE, previously used. The cesium distribution results are shown in Table 4.17 alongside those obtained from 1 M NaN03 in 1,2-DCE. 

The stability under irradiation of the calix[4]arene-bis(tm-octylbenzo-crown-6) (BOBCalixC6)-based solvent system (mixture composed of calix[4]arene, an aromatic fluoro-propanol as modifier, and trioctylamine in aliphatic diluent) was tested under chemical and radiolytic conditions representative of the alkaline-side process (265). After y-irradiation doses as high as 0.16 MGy, no significant loss of BOBCalixC6 was measured (less than 10%). 

The effect of radiolysis on complexed solutions proposed for the FPEX process was investigated. The calixarene BOBCalixC6 was present with substi-tuted-18-crown-6, aromatic fluoro-propanol as modifier, and trioctylamine in aliphatic diluents (35). The effect of gamma irradiation was negligible up to 0.02 MGy. An important change of coloration and the appearance of a third phase was observed, but due to the nitration of the modifier. Instead of the BC-6 and oct-MC6 calixarenes, which presented a decrease of Cs extraction after radiolysis, the presence of alkylated phenyl moieties provided protection for the Cs site. 

In brief, the ion exchanger is dimeric, R2H2, in aliphatic diluents (156), and the overall reaction is then... 

An isoparaffinic diluent, Isopar L, available from ExxonMobil Chemical Company, was chosen for the CSSX solvent. Isopar L is a blend of Ci0 to Cn branched alkanes with a distillation range of 185-211 °C, a viscosity of 1.6 centipoise at 25 °C, a specific gravity of 0.765-0.772 g/mL at 60 °F (15.6 °C), and a thermal closed-cup flash point of at least 60 °C (data courtesy of ExxonMobil Chemical Company). Aliphatic diluents are... 

The diluent is chosen for its case of phase separation after extraction, low cost, and safety in handling (low toxicity and flammability). Ordinarily the diluent plays no chemical role, although in some cases the metal extraction equilibria have been found to depend on whether an aromatic or an aliphatic diluent is used. 

The ion exchanger is known to be in dimeric form in aliphatic diluents [30], and the stoichiometry in Eq. (7) was found with classical slope analysis at low concentrations and FTIR-analysis even at high concentrations [31, 32], A compilation of all thermodynamic parameters is given in http //dechema.de/Extraktion/, as this system is a recommended test system for reactive extraction studies by the European Federation of Chemical Engineering (EFCE). The predictability of the model is quite good, as is depicted in Fig. 10.10, where zinc extraction from chloride media is predicted from sulfate media [33],... 

Figure 1 shows the extraction behavior of the actinide elements when a HLLW solution is contacted with a solution of 1 M HDEHP (di(2-ethylhexyl)phosphoric acid) in an aliphatic diluent (Nysolvin 75A). It is evident from this Figure that a good extraction of all actinide elements can not be obtained at any single acidity. This led us to the decision to first extract Pa,... 

Supported liquid membranes, consisting of an organic solution of -octyl(phenyl)-A,iV-diisobutylcarbamoylmethylpho-sphine oxide (CMPO) and tributyl-phosphate (TBP) in decalin, were capable of selective separation and concentration of actinide and lanthanide ions from aqueous nitrate feed solutions and from synthetic nuclear wastes where the strip solution is a mixture of formic acid (FA) and hydroxylammonium formate (HAF) [106,107]. TBP is added to CMPO to improve its solubility in aliphatic diluents. Although low concentration of nitric acid was initially used as the strippant solution, a gradual... 

The extraction of Pa(IV) by benzoylacetone (HBA) from perchloric acid and sodium perchlorate was investigated in a recent study of the equilibria in diketone extraction. The indicated reaction is reported to be the same as that given in Eq. (8), where M = PaO or Pa(0H) + (79). Diketones have also been used in the study of aqueous complexation. Oxalate (80), sulfate, and fluoride complexing of Np(IV), Pu(IV) and Th(IV) have been studied by thenoyl trifluoroacetone (TTA) extraction. The Dj is always higher when TTA is dissolved in benzene than when it is dissolved in ii-hexane (81), which is contrary to the usual observation of higher D s in aliphatic diluents. 

As used in the tri-n-butyl phosphate (TBP), or PUREX, process to recover uranium (U) and plutonium (Pu), the solvent is typically a blend of about 30 vol% TBP and 70 vol% of an aliphatic diluent, say C-12 to C-15 branched paraffins. Spent nuclear fueP is dissolved in nitric acid and then contacted with this TBP solvent. Actinide elements, primarily uranium and plutonium, are coextracted into the organic layer by coordination and solvation with TBP. The extraction of uranium, for example, is thought to occur by the following reaction [14-21] ... 

Reformulating to reduce HAP solvents frequently means that solvent blend costs increase. The newer blends are generally not be as effective. For example, many coatings were usually formulated using ketones as the active solvents with aromatic hydrocarbons as diluents. This combination produced the most cost-effective formulations. However, when MEK, MIBK, toluene, and xylene became HAP compounds, less-effective solvents had to be used for reformulation. Esters are the most common ketone replacements, and aliphatic diluents would replace the aromatic hydrocarbons. In this situation, more strong solvent is required compared to the ketone/aromatic formulation and costs increase. The combination of reduced VOC emissions and composition constraints in the form of HAP restrictions have complicated the formulator s task. 

Alternative slurry and gas phase processes for the production of EPDM are an improvement with respect to the solvent recovery step [2]. However, in gas phase processes the possibility of incorporating large amounts of heavier monomers is hmited because of the low vapor pressure of these monomers. Furthermore, conventional slurry processes use aliphatic diluents such as iso-butane or, in some processes, supercritical propane, which are highly flammable. 

In Fig. 16 we show the Arrhenius plots for SAMs formed from an aliphatic diluent and one of two ferrocene moieties (A and B, see Ref. 3 for further details) ... 

Solubility Characteristics Soluble in esters, ketones, ether/alcohol mixtures, glycol ethers. Excellent tolerance for aromatic diluent (toluene), le.ss tolerant for aliphatic diluents Formulating Considerations Avoid drying out during processing Supplier Aqualon... 

A number of more recent reports have discussed applications, process experience, and modifications of TALSPEAK. Kosyakov and Yerin (1980) report that the Cm extraction from TALSPEAK-type aqueous solutions using HDEHP/decane solutions both extractant (HDEHP) and acid dependence are reduced to two, indicating the extraction of. a 1 1M-Iactate complex for the aliphatic diluent. Similar extractant dependencies were reported for Bk, Eu, and Ce. The extraction reaction is established as independent of [DTPA] (i.e., DTPA complexes are not extracted). 

Most western countries have legislated reductions of hydrocarbon emissions. In SX plants, this means a tendency away from the use of aromatic components. In Africa, Australia, and South America, diluents containing 20 to 25% aromatic contents are still common, while in North America, diluents seldom contain more than 5% aromatics. Some processes, however, require 100% aromatic diluents because of their solvation properties. The uranium and precious metals industries often employ aromatic diluents, while cobalt, nickel, and zinc systems can anploy 100% aliphatic diluents. 

A summaiy of operating conditions is shown in table I. The organics used in the field tests contained the following components M5640 extractant (an aldoxime obtained from 2 neca, Inc), Paranox 100 surfactant (a nonionic, polyamine compound obtained from Exxon Inc), and a mixture of Isopar M and V kerosenes (aliphatic diluents obtained from Exxon, Inc). Water-in-oil type emulsions were generated between the organic phases and the indicated internal solutions. Optimum average internal droplet size was about 5 f/m in diameter. 

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