Aluminum nitrate concentration, effect

In addition to the effect of pH on mobility, the type of acid entering environmental systems may also be important. Nitric acid was found to leach more aluminum from soil columns representative of high-elevation forest floor soils than did sulfuric acid (James and Riha 1989). This is most likely due to the higher solubility of aluminum nitrate than aluminum sulfate. However, in mineral horizons below the forest floor, the study found that concentrations of aluminum leached by these acids did not differ from concentrations of aluminum leached by distilled, deionized water at a pH of 5.7. The authors concluded... 

Fixation figure (2) shows the effect of free acidity and Notion deficiency on Kj) (Cm3+) for concentrated solutions containing aluminum nitrate. Extraction is carried out by TBP impregnated on G.C.Q. (l. m.mole TBP g. loaded stationary phase). Kj) (Cm3+) can be observed to be highly sensitive to acidity in the neutral region the maximum Kj) (Cm3+) (- 250) is obtained for an NOT ion deficiency equal to 0.05 0.05. This result is similar to that obtained in liquid-liquid extraction. 

In certain applications, the quaternary ammonium salts have advantages over tertiary amines for actinide extractions. Quantitative extraction of the transplutonium elements from nitrate media by quaternary ammonium salts can be achieved with a lower aqueous-phase nitrate concentration than is required for tertiary amines thus, aluminum nitrate may be used instead of lithium nitrate. The separation factor between Am and Cm can be as high as three in a quaternary ammonium nitrate system (50). The effect of the length of the alkyl chain on Cm, Am, Bk, Cf, and Es extraction by alkyldioctylammonium nitrates suggests that steric factors substantially influence the extraction selectivity (51). A comparison of the extraction of tetravalent and hexavalent actinides by tetraheptyl ammonium nitrate shows that tetravalent ions are more easily extracted than hexavalent ions e.g.,... 

Wang et al. (2002) demonstrated a composite membrane (subjected to PV) of an asymmetric poly(4-methyl-l-pentene) (TPX) membrane dip-coated with poly(acrylic acid) (PAA). To improve the interface peeling of the PA A/TPX composite membranes, the surfaces of TPX membranes were modified by residual air plasma in a tubular-type reactor. The plasma treatments were effective in rendering the asymmetric TPX membrane hydrophilic. Optimal results were obtained with PAA/TPX composite membrane prepared from the PAA/ethylene glycol (EG)/aluminum nitrate = 1/2/0.05 coating solution at 5 W/30 s plasma treatment condition. Concentration of the water in the permeate was nearly 100%, and a permeate flux of 960 g/m h was obtained with a 3 wt% feed acetic acid concentration. 

In the procedure of Rodden and Tregonnlng,- — aluminum nitrate Is used Instead of magnesium nitrate If extraction la to be made In the presence of diosxAiate. DeSesa and NJetzelfoimd that 1 molar concentrations of phosphate, sulfate, or carbonate Ion could be tolerated with no 111 effect on uranium extraction. Small amounts of sodium phosphate have been used to suppress the extraction of thorium without affecting the extraction of iranlum. Steele and Taverner- report the extraction of appreciable amounts of thorium and zirconium and small amounts of vanadium, molybdenum, and platinum by ethyl acetate. 

Ammonium Nitrate.— The weak liquors are usually concentrated from 25 to 80 per cent in single effects of the horizontal-tube, or special vertical-tube evaporators. The steam pressure is from 5 to 20 lb. and the vacuum from 18 to 26 in. Evaporators have been built with cast-iron shells and cast-iron tubes, and also with aluminum tubes and enameled bodies. 

For solutions with ionic strengths of 0.1 M or less, the electrolyte effect is independent of the kind of ions and dependent only on the ionic strength. Thus, the solubility of barium sulfate is the same in aqueous sodium iodide, potassium nitrate, or aluminum chloride provided the concentrations of these species are such that the ionic strengths are identical. Note that this independence with respect to electrolyte species disappears at high ionic strengths. 

Scientists have developed computer models that depict the physical, chemical and biological processes within forest watersheds. Watershed acidification models can be used as research and management tools to investigate factors responsible for the historical acidification of soil and water as well as the ecosystem response to anticipated future changes in acidic deposition. In order to effectively predict the pH, ANC and aluminum concentrations in streams, all major chemicals must be accurately simulated (e.g., sulfate, nitrate, calcium, magnesium). The acidification model PnET-BGC was used for this assessment because it has been rigorously tested at Hubbard Brook and other sites in the northeastern United States, and it allows the user of the model to consider the ecosystem response to multiple chemicals simultaneously. Other frequently used acidification models include MAGIC (Cosby et al. 2001), and NuCM (Lui et al. 1992). 

Barium nitrate would be the best of the three from the standpoint of physical stability and also of heat concentration because barium oxide has considerably better refractory properties than either potassium or sodium oxide. However, the high equivalent weight of barium limits its usefulness. Barium and strontium nitrates are indispensable for green and red effects and can also be used combined for white light. In combination with potassium perchlorate and aluminum, barium nitrate is part of standard photoflash powder. Ammonium and guanidine nitrate are sometimes used because of their gas-forming properties, and lead and silver nitrate can be found in special applications. 

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