Acidity grade

Consumer stocks (2) at the end of 1993 were 65,000 t. The National Defense Stockpile of fluorspar iaventory, at year end 1992, contained 809,000 t of acid-grade material, 281,000 t of metallurgical-grade material, 816 t of nonstockpile, acid-grade material, and 105,938 t of nonstockpile, metallurgical-grade material. 

The prices for acid-grade fluorspar dry basis from Mexico and the RepubHc of South Africa for 1993 were Mexican spar, fob Tampico,... 

Table 6. Analyses of Ceramic- and Acid-Grade Fluorspar, wt...

Fluorspar. A typical acid-grade fluorspar analysis gives ... 

Based on previous spHts ia milling operations, about a 60% yield or 146 x 10 t of acid-grade spar could be expected. At the production rates of the early 1990s, this would be a 24-yr supply. Additional suppHes are expected to be brought iato production, however, and no decline ia available reserves is expected through the year 2000. 

Most of the acid-grade spar used for HF production ia the United States is imported. More than two-thkds of the fluorspar consumed ia the United States goes iato production of HF nearly 30% is consumed as a flux ia steelmaking and the remainder is consumed ia glass manufacture, enamels, welding rod coatings, and other end uses or products (see Fluorine compounds, inorganic-calcium). 

Acid Oxidation. Reactions of lead with acid and alkaUes are varied. Nitric acid, the best solvent for lead, forms lead nitrate acetic acid forms soluble lead acetate in the presence of oxygen sulfuric acid forms insoluble lead sulfate. Sulfuric acid is stored in containers with chemical or acid-grade lead. Lead dissolves slowly in HCl, but in the presence of aqueous alkaUes forms soluble plumbites and plumbates. 

Gaseous hydcofluoiic acid is generally made by the reaction of acid-grade fluorspar [14542-23-5] Cap2, with sulfuric acid (see Fluorine compounds, inorganic)... 

Anhydrous HF is almost invariably made by the action of cone H2SO4 (>95%) on acid grade fluorspar (>98% CaF2) ... 

Acid-grade feldspar, aluminum fluoride production from, 2 357—358 Acid-grade fluorspar, 4 579, 580 analysis, 4 577t Acid halides, 12 188-190 Acid hydrolysis. See also Acidic hydrolysis of wood, 26 358 of wool, 26 376 Acid hydrolysis lignin, 15 21 Acidic catalysts, 10 556. See also Acid catalysts... 

Feely-Beavers procedure, 21 99 Feldspar(s), 2 344 5 640. See also Acid grade feldspar in clays, 6 685 in coal, 6 718 in kaolinite, 6 659 Feline central retinal degeneration (FCRD), 10 856... 

The sample introduction unit was constructed from inert materials, which minimizes the introduction of metal contamination into the system. The samples or digestion acids make contact only with PTFE, Kel-F, glass, acid-resistant rubber and platinum-iridium (9 + 1) alloy. In addition, the construction materials were Hmited to acid-grade Arborite (ureaformaldehyde laminate). Perspex and stainless-steel. The unit was constructed in three continuous sections a heated sample compartment, a turntable mechanism and heat-exchanger compartment, and a pump compartment. 

Materials of construction SS304L ( nitric acid grade ) ... 

A storage tank for product nitric acid is a necessity on this plant. The tank should have the capacity to store one week of full acid production to allow for continued supply in the event of unscheduled shutdowns in the adjacent ammonium nitrate plant. This requires a minimum tank capacity of 1500 m3. However, it is recommended to increase the tank capacity so that an inventory of 450 m3 of product acid is always available within the tank for outside sales. This extra volume is equivalent to 20 standard road-tanker loads. The tank must be constructed of stainless steel type 304L ( nitric acid grade ), the specification of this material is given in Appendix D. The design data required for this unit are specified below. 

The tank must be constructed of stainless steel type 304L ( nitric acid grade ), the specification of this material is given in Appendix D. 

Table 9.12. Nitric Acid Grades and Their Content...

The unsaturation, as determined by the iodine value (IV), decreases from an IV of 10.0 for a single press to an IV of 1.0 for a triple press stearic acid grade. 

Table III Specifications of different stearic acid grades.

Table 1.7-2. Analysis of Ceramic and Acid Grades of Fluorspar in wt%.

Properties Colorless needles. Mp 153C, bp 307C, d 1.212 (15/4C). Slightly soluble in water soluble in alcohol, ether, ethyl acetate, glacial acetic acid. Grade Technical. 

Properties Water-white, high-boiling hquid mild odor. Bp 240-250C, refr index 1.425, fp -30C, wt/ gal approximately 8.24 lb (20C), flash p 220F (104.4C) (CC). Miscible with most alcohols, ketones, esters, oils, hydrocarbons. Combustible. Derivation By the standard esterification process using normal butyl alcohol and oxalic acid. Grade According to ester content 90%, 95%, 99-100%. 

Derivation Condensation of p-chlorophenol with formaldehyde in the presence of sulfuric acid. Grade Pure and technical. 

Derivation Action of chlorine on ethylene, with subsequent distillation with metallic catalyst also by reaction of acetylene and hydrochloric acid. Grade Technical, spectrophotometric. 

Derivation Treating ethanol with propionic acid. Grade Commercial 85-90% ester content, FCC. Hazard Flammable, dangerous fire risk. 

Properties Colorless solid fatty repulsive odor. D 0.830-0.836, refr index 1.428, mp 24C, bp 259C, flash p above 212F (100C) (CC). Insoluble in water soluble in two parts of 70% alcohol. Combustible. Derivation Reduction of coconut-oil fatty acids. Grade Technical, FCC. 

Phosphatase, acid Origin potato Roche Diagnostics Phosphatase, acid, grade II... 

Aluminum fluoride is important as an additive to the electrolyte of aluminum smelting cells. Wodd production, about 700,000 t/yr, is hy the hydrofluoric acid [7664-39-3] HV process and the fluorosihcic acid [16961-83 ], H SiF, process. In the HF process, acid grade feldspar [7789-75-5], CaF, reacts in a rotary kiln with filming sulfuric acid (oleum) [8014-95-7], H SO SO, to produce anhydrous HF gas and gypsum (see Fluorine compounds, INORGANIC, hydrogen)... 

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