Colloidal solution, sulfuric acid

Hydrolysis of solutions of Ti(IV) salts leads to precipitation of a hydrated titanium dioxide. The composition and properties of this product depend critically on the precipitation conditions, including the reactant concentration, temperature, pH, and choice of the salt (46—49). At room temperature, a voluminous and gelatinous precipitate forms. This has been referred to as orthotitanic acid [20338-08-3] and has been represented by the nominal formula Ti02 2H20 (Ti(OH). The gelatinous precipitate either redissolves or peptizes to a colloidal suspension ia dilute hydrochloric or nitric acids. If the suspension is boiled, or if precipitation is from hot solutions, a less-hydrated oxide forms. This has been referred to as metatitanic acid [12026-28-7] nominal formula Ti02 H2O (TiO(OH)2). The latter precipitate is more difficult to dissolve ia acid and is only soluble ia concentrated sulfuric acid or hydrofluoric acid. 

Zinc electrowinning Zinc in a sulfuric acid/ aqueous solution, lead-silver alloy anodes, aluminum cathodes, barium carbonate, or strontium, colloidal additives... 

The amounts oi adsorption of the polymer on latex and silica particles were measured as follows. Three milliliters of the polymer solution containing a known concentration was introduced into an adsorption tube(lO ml volume) which contained 2 ml of latex (C = l+.O wt %) and silica(C = 2.0 wt %) suspensions. After being rotated(l0 rpm) end-over-end for 1 hr in a water bath at a constant temperature, the colloid particles were separated from the solution by centrifugation(25000 G, 30 min.) under a controlled temperature. The polymer concentration that remained in the supernatant was measured colorimetrically, using sulfuric acid and phenol for the cellulose derivatives(12), and potassium iodide, iodine and boric acid for PVA(13). From these measurements, the number of milligrams of adsorbed polymer per square meter of the adsorbent surface was calculated using a calibration curve. 

A sulfuric acid solution of the oxide (25-75% solution) can be reduced with tin, copper, zinc, and other reducing agents forming a blue solution of molybdenum blue which are hydrous oxides of non-stoichiometric compositions (see Molybdenum Blue). Reduction with atomic hydrogen under carefully controlled conditions yields colloidal dispersion of compounds that have probable compositions Mo204(OH)2 and Mo40io(OH)2. Reduction with lithium aluminum hydride yields a red compound of probable composition MosOtIOEOs. Molybdenum(Vl) oxide suspension in water also can be reduced to molybdenum blue by hydriodic acid, hydrazine, sulfur dioxide, and other reductants. 

Silica gel is synthetic amorphous silica consisting of a compact network of spherical colloidal silica particles. Its surface area is typically between 300 and 850 m2/g. The predominant pore diameters are in the range 22-150 A. Silica gel is produced via the following procedure a sodium silicate solution reacts with a mineral acid, such as sulfuric acid, producing a concentrated dispersion of finely divided particles of hydrated Si02,... 

FIG. 3 Colloidal aggregate formed in the air-water interface. The aggregated particles are polystyrene spheres of diameter 2.26 /un. In the air-water interface the particles develop an electric-dipole perpendicular to the surface, which prevents them from aggregating. Aggregation is induced by adding to the water solution a small amount of electrolyte which screen the dipolar interaction. In the sample shown here, sulfuric acid was added to the water until a pH of 2 was reached. Courtesy of Prof. Jaime Ruiz-Garcia, Instituto de Fisica, Universidad Autonoma de San Luis Potosi. 

This fraction was obtained by precipitation with acetone from an ethereal extract of the cells. It formed acidic colloidal solutions with water and contained 0.37% nitrogen and 2.16% phosphorus. On hydrolysis with 5% sulfuric acid, 33.6% of water-soluble components and 65% of fatty acids were obtained. The hydrolysate contained glycerophos-phoric acid, inositol, D-mannose, and an unidentified hexose, which... 

Sulfur forms three binary compounds with indium, In2S, InS, and In2S3. The latter is prepared by direct union of the elements, by heating ln208 with sulfur or H2S or by passing H2S into the weakly acid solution of an indium salt. The precipitated form is yellow, and the salt formed by dry methods varies from yellow to brown. It is soluble in mineral acids, readily forms colloidal solutions, and gives complex salts with the alkali sulfides, such as K2In2S . 

The yellow sulfate is produced on solution of moist hydrated rhodium (III) oxide (rhodium hydroxide) in dilute (1 10) sulfuric acid at temperatures not exceeding 50 °C. Then the hydrated Rh (in) oxide is precipitated from the cold solution with KOH (avoiding an excess of the latter) and washed on a membrane filter until the colloidal hydroxide passes through. Suction is then applied and as much water as possible is removed the residue is dissolved without heating in dilute sulfuric acid. 

An aqueous solution of electrochemically oxidized graphite has been tested as an additive to the sulfuric acid electrolyte [47]. The carbon colloid addition improves the discharge capacity and extends the cycle life of the battery. This additive improves the electrical contact between Pb02 particles in the positive plates and thus increases the discharge capacity and the charge acceptance of the lead—acid battery. 

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