Hydrolyzed aluminum

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. 

The Role of Adsorption of Hydrolyzed Aluminum in the Kinetics of Coagulation... 

One can distinguish the following steps in the agglomeration of silica dispersions with hydrolyzed aluminum (1) hydrolysis and multimerization of Al(III) to isopolycations (2) diffusion of these aluminum hydroxo complexes to the colloid surface and adsorption and (3) transport of suspended particles and collision resulting in certain instances in attachment of colloids. The transport of colloids to each other has been observed to proceed more slowly than all other steps under the given circumstances (3). It follows that the rate of agglomeration, — dN/dt, is obtained from the collision frequency, as determined solely by the trans-... 

The first step is a carbonyl ene reaction, also known in the literature as a Prins reaction.7 A Lewis acid activates formaldehyde (25) for attack on the double bond of 12. This results in zwitterionic intermediate 26, which leads to the ene product 27 in the form of a dimethylaluminum complex through 1,5-migration of a proton. This complex is unstable and spontaneously eliminates methane. Aqueous workup hydrolyzes aluminum alkoxide 28 to alcohol 24. 

Strong mineral acids react with clays to hydrolyze aluminum-oxygen bonds. The aluminum dissolves, leaving an altered structure. Protons in the acid also exchange with sodium and other alkali cations, leaving an acidic material. Houdry took advantage of such reactions in making the active acidic catalysts... 

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,... 

Use of either an excess of aluminum chloride or partially hydrolyzed aluminum chloride gives larger amounts of the by-product diaryl ketone at the expense of the acid chloride. The checkers used freshly opened containers of the anhydrous material available from Fisher Scientific. 

Figure 3 solution spectra of almost fully hydrolyzed aluminum chloride solu-... 

The class of compounds identified as basic aluminum chlorides [1327-41 -9] is used primarily in deoderant, antiperspkant, and fungicidal preparations. They have the formula Al2(OH)g where x = 1 5, and are prepared by the reaction of an excess of aluminum with 5—15% hydrochloric acid at a temperature of 67—97°C (18). The same compounds are obtained by hydrolyzing aluminum alkoxides with hydrochloric acid (19,20) (see Alkoxides, metal). Basic aluminum chloride has also been prepared by the reaction of an equivalent or less of hydrochloric acid with aluminum hydroxide at 117—980 kPa (17—143 psi) (20). 

Pure nordstrandite has been prepared (5) by reaction of aluminum, aluminum hydroxide gel, or hydrolyzable aluminum compovmds with aqueous etliylenediamine [107-15-3]. However, no commercial production or uses have been reported. 

Stable particulate alumina sols are precursors for many materials such as controlled porosity catalysts, ceramics, and coatings. They are commonly formed by peptization of pseudoboehmites (AIOOHKH2O) by dilute monoprotic acids. They can be prepared either by the process developed hy Yoldas [4] from hydrolyzed aluminum alkoxides or by acidic peptization of the precipitates derived from hydrolyzed aluminum salts [5,48]. As will be seen below, these alumina sols are usually multi-component fluids that also contain soluble aluminum species. Furthermore, colloidal aluminas can also be produced by the polymerization of hydrolyzed aluminum cations. Therefore, a brief review on the characterization of aluminum species in solution by At NMR is presented in Sec. III.B.l. The NMR studies on colloidal aluminas are then discussed in Sec. III.B.2. 

Although hydrolysis and condensation proceed differently in alkoxide systems than in aqueous systems [3], similar Al NMR speciation and sensitivity to the synthesis conditions are found in the hydrolyzed aluminum solutions that can be used as precursors to sol-gels. In comparison to silica (Sec. UFA), the rates of hydrolysis of aluminum precursors are very fast, and nonhydrolyzed Al(OR)3 oligomers are scarce in the resultant alumina sols. Therefore, the influence of organic... 

Coagulation of silver halide by hydrolyzed aluminum salts was shown by Matijevi6, Kratohvil, and Sticles (267) to be inhibited by fluoride ion which formed complex ions with aluminum. Similar reduction in coagulation effectiveness of other metal cations such as Fe and Th on colloidal silica may be anticipated. 

To date, potentiometric titration is still a main approach to study the surface acid base chemistry of clay minerals. Only some papers deal with the dissolution of a solid matrix resulting in various hydrolyzed aluminum species, silicic acid and their product hydrous aluminosilicates, though their interaction with a clay surface should be considered in the modeling description. The surface complexation model (SCM) was successfully applied in a recent paper [6] to interpret surface acid-base reactions involving the dissolution of illite clays during prolonged titration. Voluminous literature on ion adsorption and surface complexation... 

The specific interaction of glicdoxy propyl trimethoxysilane with hydrolyzed aluminum. 

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