Acid Hydrochloric Hydrofluoric

The concept of chemically removing pyrites from coal has not previously been advanced as a solution to the sulfur oxide air pollution problem because iron pyrites are not soluble in any known liquids. For example, the acids hydrochloric, hydrofluoric, sulfuric, or combinations of... 

Chem. Descrip. Quat. ammonium chloride Uses Surfactant foaming agent for strong acids (hydrochloric, hydrofluoric, sulfuric) used in aluminum trailer cleaner, brightener, acid inhibitors and cleaners, chrome plating baths Properties Dk. amber liq. dens. 8.8 Ib/gal pH 6-9 (5%) cationic 100% cone. 

Acid Treatment. The treatment of petroleum products with acids has been in use for a considerable time in the petroleum industry. Various acids such as hydrofluoric acid, hydrochloric acid, nitric acid, and phosphoric acid have been used in addition to the most commonly used sulfuric acid, but in most instances there is Httie advantage in using any acid other than sulfuric. 

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. 

The reactivity of titanium dioxide toward acid is dependent on the temperature to which it has been heated. Freshly precipitated titanium dioxide is soluble iu concentrated hydrochloric acid. However, titanium dioxide that has been heated to 900°C is almost iusoluble iu acids except hot concentrated sulfuric, iu which the solubiUty may be further iucreased by the addition of ammonium sulfate to raise the boiling poiut of the acid, and hydrofluoric acid. Similarly, titanium dioxide that has been calciued at 900°C is almost iusoluble iu aqueous alkahes but dissolves iu molten sodium or potassium hydroxide, carbouates, or borates. 

Chromium is highly acid-resistant and is only attacked by hydrochloric, hydrofluoric, and sulfuric acids. It is also resistant to other common corroding agents including acetone, alcohols, ammonia, carbon dioxide, carbon disulfide, foodstuffs, petroleum products, phenols, sodium hydroxide, and sulfur dioxide. 

Hydrobromic, hydrochloric, hydrofluoric and hydroiodic acids Methacrylic acid Nitric acid... 

Mineral acid Hydrobromic acid Hydrochloric acid Hydrofluoric acid Nitric acid Sulphuric acid... 

Acetylene works Acrylates works Aldehyde works Aluminum works Amines works Ammonia works Anhydride works Arsenic works Asbestos works Benzene works Beryllium works Bisulfate works Bromine works Cadmium works Carbon disulfide works Carbonyl works Caustic soda works Cement works Ceramic works Chemical fertilizer works Chlorine works Chromium works Copper works Di-isocyanate works Electricity works Fiber works Fluorine works Gas liquor works Gas and coke works Hydrochloric acid works Hydrofluoric acid works Hydrogen cyanide works Incineration works Iron works and steel works... 

Acids Molybdenum exhibits good resistance to hydrochloric, hydrofluoric, phosphoric and sulphuric acids (see Figs. 5.2, 5.3 and 5.4). In static tests in these acids at Ohio State University it was found that the corrosion rate for relatively long test periods (670 h) was about ten times that experienced in 47 h tests. 

Stimulation by dissolving certain components of the reservoir rock with hydrochloric, hydrofluoric or acetic acid, or by other chemical substances. 

Hydrochloric acid, 42 Hydrofluoric acid, storage of, 361 Hydrogen, 99... 

For analytical purposes silicates may be conveniendy divided into the following two classes (a) those ( soluble silicates) which are decomposed by acids, such as hydrochloric acid, to form silicic acid and the salts (e.g. chlorides) of the metals present and (b) those ( insoluble silicates) which are not decomposed by any acid, except hydrofluoric acid. There are also many silicates which are partially decomposed by acids for analytical purposes these will be included in class (b). 

Both inorganic acids, such as hydrochloric acid and hydrofluoric acid, and organic acids, such as formic acid, can be used to increase the pH. Acids are used in combination with surfactants. Various phosphates, pyrophosphates. 

Hydrofluoric acid may be prepared by dilution of a concentrated aqueous solution or by reaction of enough ammonium bifluoride with aqueous 15% HC1 to prepare a 12% HCl/3% HF solution. Hydrochloric - hydrofluoric acid blends have the major advantage of dissolving silicaceous mineral including clays and silica fine particles. HCl/HF blends are quite corrosive. 

Mixed acid systems are blends of mineral acids and organic acids. Combinations that have been used in carbonate acidizing include acetic acid/HCl and formic acid/HCl. While these are less corrosive than hydrochloric acid alone, the organic acid may not react completely with the rock. Blends of formic acid and hydrofluoric acid have been used in high temperature sandstone acidizing and are less corrosive than HC1/HF blends. 

Engelhardt, F., Kuhlein, K., Riegel, U., von Halasz, S., Dawson, J.C., and Reed, A.R. "Water Soluble Copolymers for Use in Fracture Acidizing of Wells," US Patent 4,500,437(1985). Holcomb, D.L., Jr. "A New Concept in Hydrochloric-Hydrofluoric Acid Mixtures for Acidizing Low Permeability Sandstone Formations," 1974 Proc. Annu. Southwest. Pet. Short Course, Lubbock, 41 8. 

Holcomb, D.L. "Low Concentration Hydrochloric-Hydrofluoric Acid Mixtures for Stimulation in Low Porosity, Low Permeability Sandstone Formations," Proc. Svmp. Stimul, Low Permeability Reservoirs.1976. 72-86, Colo. Sch. Mines, Golden. 

Hydrochloric acid or Hydrofluoric acid Kirk-Othmer, 1963, Vol. 1, 952 The metal is attacked violently by the aqueous acids. 

Caesium 137Cs adsorption on strong cation exchange resin ammonium hexacyano cobalt ferrate, dissolution in hydrochloric hydrofluoric acid /f counted for 137Cs lOpCi/1 [865]... 

In this method approximately 19 samples of marine sediment were oven dried at 110°C then digested with nitric acid-perchloric acid and hydrofluoric acid-hydrochloric acid. The digested solution is made up to 50ml of an equal volume mixture of 6M hydrochloric acid and 2M nitric acid. 0.1ml or less of the digest was pipetted into the hydride generator, followed by 1ml 2M acetic acid, diluted to 100ml with double distilled water and reacted with sodium borohydride. 

At Los Alamos National Laboratory, the silicon content of plutonium samples is determined spectrophotometrically using a silica-molybdenum blue complex ion, which has a blue color. The sample is dissolved in a mixture of hydrochloric acid and hydrofluoric acid. After the excess hydrofluoric acid is removed, the absorbance is measured at 825 nm. All operations are carried out in a silica-free apparatus. 

Wet chemical decomposition in a closed system, with nitric acid or mixed acids consisting of nitric acid, hydrochloric acid, perchloric acid, hydrogen peroxide and hydrofluoric acid. The following devices are available ... 

Greyish tetragonal or monochnic crystals density 6.47 g/cm insoluble in water shghtly soluble in hot concentrated sulfuric acid insoluble in alkabes, hydrochloric acid and hydrofluoric acid. 

Non-Oxidizing Mineral Acids Hydrochloric Acid Hydrofluoric Acid Phosphoric Acid... 

The inevitable introduction of acids such as hydrochloric, hydrofluoric, bases, metallic halides, carbonates and gases like carbon dioxide and nitrogen create another set of problems for the seal. The oil field duty condition is very critical and unique, and therefore there is very little technology transfer potential. 

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