Removal aluminum

Fig. 1. Flow diagram for aluminothermic process showiag alternative methods of aluminum removal from alloy regulus.

Removal of aluminum from the feed to the SCWO reactor. At this time, Eco Logic has not proposed an aluminum removal technology. 

Eco Fogic must remove aluminum from the feed to the SCWO and intends to use a process based on General Atomics aluminum removal technol-... 

MD M28 rocket propellant and burster hydrolysates slurried with shredded and micronized dunnage that has had the hydrolyzed aluminum removed by filtration. These tests included the results of aluminum filtration tests. This test also demonstrated a modified chemistry for controlling solids transport through the reactor without the use of an additive that degrades the titanium reactor material. 

Kerr, Plank, and Rosinski reported the preparation and catalytic properties of aluminum-deficient zeolite Y materials 35). Topchieva and co-workers studied the catalytic properties of cationic forms of aluminum-deficient Y zeolites, the aluminum deficiency being effected by the H4EDTA method 36-40). They found that up to 50% aluminum removal increased both stability and cumene cracking activity maximum activity was observed at the 50% removal level. Increased catalytic cracking activity was observed by Eberly and Kimberlin for mordenites from which about 80% aluminum had been removed (. 1). Weiss et al. removed over 99% of the aluminum from a hydrogen mordenite and found the zeolite retained catalytic activity of the type induced by Bronsted acids 42). Although the initial activity of this material was lower than that of more aluminum-rich mordenites, the aging rate was markedly reduced, and in a relatively short time the aluminum-deficient catalyst was the most active. 

An opposing effect is possible under the severe conditions of a single extraction with HC1 some of the aluminum removed from the crystal structure may not be transported out of the catalyst particle. The resulting amorphous alumina, (after subsequent calcining) remaining in the particle would cause some reduction in effective diffusivity. Such amorphous alumina has been suggested by others (17,18). 

Jacobs and Uytterhoeven (199, 200) observed a band in the 3700 to 3675 cm-1 region in addition to the bands reported by Ward. The intensities of the acidic bands at 3650 and 3550 cm-1 were greater than those observed by Ward, which probably resulted from a lesser degree of aluminum removal. The new bands at 3700 and 3600 cm-1 arose from hydroxyls that were nonacidic to ammonia (199, 200) and pyridine (198, 199), although bands from pyridinium ions were observed in the IR spectrum. The latter bands were attributed to interaction of pyridine with the 3650 cm-1 hydroxyls (200). Jacobs and Uytterhoeven (199) and Scherzer and Bass (198) attributed the 3700 and 3600 cm-1 bands to structural hydroxyl groups associated with removal of aluminum from the zeolite framework. The 3600 cm-1 band arose from weakly acidic hydroxyls (200) since the band was removed by treatment with 0.1 W NaOH solution. The 3700 cm-1 band was unaffected by a similar treatment. 

In contrast, Kim et al. (13) found that the amount of aluminum removed from the zeolite lattice during ion-exchange with solutions of metal chlorides was directly related to the pH of the solution and that the presence of the metal cation played no part in the dealumination. Our work more closely mirrors that of Bailar and coworkers (14-16) who found that solutions of CrCl3 under reflux conditions could dealuminate a variety of zeolites to a much greater extent than the pH of the CrCl3 solutions would predict. To explain their results, they proposed that the chromium cations could complex with hydrolyzed aluminum ions in the zeolite through the formation of "ol bridges" which then diffused out of the zeolite. Therefore,... 

Y-zeolite (Si02/Al203 framework = 59), in which the aluminum removed from the framework remains in the zeolite as extra framework aluminum (total SiCyA Oj = 5.2) (Bezman, 1991). By electron microscopy, the crystal sizes were found to be of the order of 1... 

The framework silicon distribution depends on the mechanism of aluminum removal and silicon replacement during preparation. These differences remain after calcination but disappear upon steaming. Severe steaming results in loss of a large portion of framework aluminum such that only the strongest-bound aluminum species remain in the framework. Consequently, steamed AFS and USY zeolites have similar framework silicon distributions. 

Toxic disorders Drug, narcotic, heavy metals Organic toxins Medications (prescription) Alcohol consumption Dialysis dementia (aluminum) Removal of offending toxin... 

Weiss LG, Danielson BG, Fellstrom B, et al. Aluminum removal with hemodialysis, hemofiltration and charcoal hemoperfusion in uremic patients after desferrioxamine infusion. A comparison of efficiency. Nephron. 1989 51 325-329... 

The Raney nickel alloy will react with water at 70°-85°C to give the skeletal nickel in the presence of aluminum hydroxide. The resulting catalyst is active after washing with alcohol . Since no base is present, the extensive water washings are not required. The reaction with water can be promoted by the addition of a small amount of base, and, further, some Bayerite, Al(OH)3, to further facilitate the aluminum removal. ... 

The aluminum nickel alloy possesses the characteristics which are not possessed hy an alloy containing these same substances and silicon. That is, the nickel aluminum ally) may be either very finely pulverized, say to 200 mesh, or it may be broken in pieces the size- of peas or smaller. In either condition the alloy may be treated with caustic soda or the aluminum removed with the use of some other solvent. In ease the larger pieces are used, the nickel is left in a more or less spongy and porous state, somewhat similar to a cinder, and for certain classes of work is is necessary and desirable to have the catalyzer in this condition. I find this characteristic peculiar to the aluminum nickel alloy. Source Raney 1927... 

Aluminum-27 NMR spectra show that after crystallization, all the TOA-containing zeolites exhibit a well resolved resonance at <50 ppm, corresponding to framework Al(IV) atoms. However, following NH.- exchange and calcination in air at 500°C, a new band appears at abdut 0 ppm due to Al(VI) resulting from aluminum removed from the crystal lattice. In general, calculated Si/Al ratio from silicon-29 NMR data are in reasonable agreement with chemical analysis results. Thus, all the aluminum atoms in these siliceous mordenite and Al-rich pentasils are believed to be in tetrahedral coordination and incorporated into the zeolite lattice. 

Kerr s postulation of the formation of Al(OH)2+ species as part of the mechanism for aluminum removal agrees with our x-ray findings. 

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