Aqueous from rock types

The sorption/desorption processes were studied by a batchtype technique. Aqueous solutions were prepared by mixing rock powders with distilled-deionized water. For the sorption experiments, portions of these aqueous solutions were loaded with tracer quantities of a single radioactive nuclide and contacted with wafers of a given rock type. For the desorption experiments, wafers from the sorption experiments were contacted with the remaining portions of the aqueous solutions. 

Figure 2. Sodium released to the aqueous solution during the dissolution of powders from three rock types. ( ), Eleana shale (UE-17e) (0), quartz mon-zonite (U15e-7) ( ), umtanum basalt (DC 3-3600).

Arends J, Christoffersen J, Christoffersen MR, Eckert H, Fowler BO, Heughebaert JC, Nancollas GH, Yesinowski JP, Zawacki SJ (1987) A calcium hydroxylapatite precipitated from an aqueous-solution —an international multimethod analysis. J Cryst Growth 84 515-532 Arey JS, Seaman JC, Bertsch PM (1999) Immobilization of uranium in contaminated sediments by hydroxyapatite addition. Environ Sci Tech 33 337-342 Belousova EA, Griffin WL, O Reilly SY, Fisher NI. (2002) Apatite as an indicator mineral for mineral exploration Trace-element compositions and their relationship to host rock type. J Geochem Explor 76 45-69... 

The extent of adsorption of eommereial surfaetants developed for use in reservoir recovery proeesses ean vary from near zero to as high as 2.5 mg/g. Surfactant adsorption on rock surfaces is usually measured by either static (batch) or dynamic (coreflood) experiments. The static adsorption method, employing crushed rock samples, is essentially the classical method for determining adsorption isotherms at the aqueous solution/solid interface and involves batch equilibrations of particles in solutions of different initial surfactant concentration. The dynamic coreflood method is more involved but employs a greater solid to liquid ratio and is therefore more sensitive, see references [J69-J7J]. Temperature, brine salinity and hardness, solution pH, rock type, wettability, and the presence of a residual oil phase have all been found to influence the extent of adsorption of different surfactants [116,152,172],... 

As can be seen, the gelatinous explosives of the Nobelite type, safe in the presence of methane, contain a small amount of calcium nitrate solution. Calcium nitrate was added to Nobelites to reduce the temperature of the flame of explosion. After World War I, small quantities of calcium nitrate in the form of a concentrated aqueous solution were added to the milled nitroglycerine powder (from the post-war surplus) used as a rock explosive. This was done to counteract dustiness e.g. Nitro-glycerinpulver 1 explosive had the following composition ... 

In the alkaline flood process, the surfactant is generated by the in situ chemical reaction between the alkali of the aqueous phase and the organic acids of the oil phase The surface-active reaction products can adsorb onto the rock surface to alter the wettability of the reservoir rock and/or can adsorb onto the oil-water interface to lower the interfacial tension. At these lowered tensions (1-10 dyne/cm), surface or shear-driven forces promote the formation of stable oil-in-water emulsions or unstable water-in-oil emulsions the nature of the emulsion phase depends on the pH, temperature, and electrolyte type and concentration. These different paths of the surface-active reaction products have created different recovery mechanisms of alkaline flooding. The four alkaline recovery mechanisms which have been cited in the recent literature are (i) Emulsification and Entrainment, (ii) Emulsification and Entrapment, (iii) Wettability Reversal from Oil-to Water-Wet, and (iv) Wettability Reversal from Water- to Oil-Wet. These four mechanisms are similar in that alkaline flooding enhances the recovery of acidic oil by two-stage processes. 

ABSTRACT. The enthalpies of transfer of cycloh xanol from aqueous to aqueous a- or 3-cyclodextrin solutions have been measured at various mole fractions at 298.15 K on a rocking twin-microcalorimeter of heat-conduction type and the molar enthalpies,Gibbs energies, and entropies of inclusion in the aqueous solutions have been determined by the method proposed by the authors [f etsu Sokutei 10,103(1983)], to elucidate the "driving force" of the molecular inclusion. Discussions are given for all the systems obtained by the authors, concluding that the "driving force" is the enhancement of the entropy. 

Results of models for the Tournemire shales are reported in Table 4. These models were based upon the mineralogical and CEC data presented in Tables 1 and 2 the calculated cation exchange selectivity coefficients and the concentrations of leachable Cl present in the rocks. Preliminary selectivity coefficients (Ac(Mg/Na) and Kc Ca./ Na) close to 3 and 4 respectively) have been derived from aqueous extraction experiments. They are in rather good agreement with literature data (Baeyens Bradbury 1994), and are mainly related to the illite and inter-stratified illite/smectite contents. The leachable Cl has been extracted with pure water at a liquid/solid ratio of 10mlg. It is clear that the Tournemire porewater cannot be definitively described with the data available. The porewater is of Na-Cl-(HCO ) type, with a low salinity, equivalent to a total dissolved... 

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