Phosphoric acid diluted

Nickel Phosphate. Tri nickel orthophosphate [14396-43-17, Ni2(P0 2 7H20, exists as apple-green plates which decompose upon heating. It is prepared by the reaction of nickel carbonate and hot dilute phosphoric acid. Nickel phosphate is an additive to control the crystal size of ziac phosphate ia coaversioa coatiags which are appHed to steel prior to its being paiated (see Metal surface treatments). 

A third screening smoke-type is white phosphoms [7723-14-0] (WP), P (see Phosphorus and THE phosphides), which reacts spontaneously with air and water vapor to produce a dense cloud of phosphoms pentoxide [1314-56-3]. An effective screen is obtained as the P2O5 hydrolyzes to form droplets of dilute phosphoric acid aerosol. WP produces smoke in great quantity, but it has certain disadvantages. Because WP has such a high heat of combustion, the smoke it produces from bulk-filled munitions has a tendency to rise in pillarlike mass. This behavior too often nullifies the screening effect, particularly in stiU air. Also, WP is very brittle, and the exploding munitions in which it is used break it into very small particles that bum rapidly. 

To the residue is added 10 c.c. of dilute phosphoric acid, prepared by miiiug alx)Ul 3 5 c.c. cf hH per cent, acid w ith 100 c.c. of carbjn dioiide-free distilled water. 

All conventional phosphate coating processes are based on dilute phosphoric acid solutions of iron, manganese and zinc primary phosphates either separately or in combination. The free phosphoric acid in these solutions reacts with the iron surface undergoing treatment in the following manner ... 

Ca5 (P04)3 F( ) + 5 H2 S04(cz - 3 H3 P04(t2 ) + 5 CaS04( ) + HF(ts The dilute phosphoric acid obtained from this process is concentrated by evaporation. It is usually dark green or brown because of the presence of many metal ion impurities in the phosphate rock. However, this impure acid is suitable for the manufacture of phosphate fertilizers, which consumes almost 90% of phosphoric acid production. 

Materials Required Thyroid gland dried 1.0 g anhydrous potassium carbonate 17.0 g bromine solution (9.6 ml of Br2 and 30 g of KBr in 100 ml DW) 7.0 ml dilute phosphoric acid (10% w/v) 42.0 ml starch iodide paper phenol solution (saturated solution of phenol in water) 5.0 ml potassium iodide solution (10% w/v in water) 0.01 N sodium thiosulphate solution starch solution. 

During the performance of a CIEF analysis, the capillary is first filled with the sample and ampholyte mixture. The focusing step begins with the immersion of the capillary in the anolyte (dilute phosphoric acid) and catholyte (dilute sodium hydroxide) solutions followed by application of high voltage. Typically, the catholyte solution is 20 to 40 mM NaOH, and the anolyte is half the catholyte molarity, e.g., 10 to 20 mM phosphoric acid. It is important that the catholyte be prepared fresh because sodium hydroxide solutions will gradually take up carbon dioxide from the atmosphere. 

Triple Superphosphate (TSP). Triple superphosphate is produced by the reaction between ground phosphate rock and phosphoric acid by one of two processes. One utilizes concentrated phosphoric acid and generates obnoxious gases. The dilute phosphoric acid process permits the ready collection of dusts and obnoxious gases generated. 

There are two useful side products. The H2Sip6 is shipped as a 20-25 % aqueous solution for fluoridation of drinking water. Fluorosilicate salts find use in ceramics, pesticides, wood preservatives, and concrete hardeners. Uranium, which occurs in many phosphate rocks in the range of 0.005-0.03% of UsOg, can be extracted from the dilute phosphoric acid after the filtration step, but this is not a primary source of the radioactive substance. The extraction plants are expensive and can only be justified when uranium prices are high. 

On the other hand, a study of the kinetics of the polymerization of propene in the presence of dilute phosphoric acid (10-50% by weight) at 260-350° and 170-410 atmospheres has shown that the rate of polymerization is proportional to the square of the gas-phase propene concentration and the first power of the acid concentration, indicating that the polymerization involves addition of an ester to an olefin rather than interaction of two molecules of ester (Monroe and Gilliland, 58). It was pointed out, however, that both mechanisms may occur side by side and that under certain circumstances (as in dilute acid) one of these mechanisms may predominate over the other. 

Propene also undergoes conjunct polymerization in the presence of dilute phosphoric acid at high temperatures and pressures (Monroe and Gilliland, 58). When propene was treated with 10-30% phosphoric acid at 260-305° and at 170-410 atmospheres pressure, the only operating variable which appreciably affected the composition of the polymer was the extent to which the feed was polymerized. At constant percentage reaction of the feed under these conditions, the temperature, pressure, and acid catalyst concentration had no effect on the product composition. At low conversions, the polymer consisted of nearly pure dimer at 50% polymerization, two-thirds of the total was dimer and even when the feed was almost completely polymerized, the dimer fraction amounted to 35-40 % of the total polymer. The dimer and trimer fractions obtained at temperatures of 305° or lower using a acid concentrations below 30% contained about 25% paraffins and little or no naphthenes or aromatic hydrocarbons. 

Dissolve 9.414 g citric acid and 18.155 g Na2HP04-2H20 in 900 ml ddH20, if necessary, correct pH by addition of diluted phosphoric acid or sodium hydroxide, then fill up to 1000 ml with ddH20. 

The United States Pharmacopoeia 23 [11] and Indonesian Pharmacopoeia IV [9] describe the assay of benzoic acid and salicylic acid in ointments. Two chromatographic columns (20 x 2.5 cm) are used to effect the separation. One transfers a mixture of 1 g siliceous earth and 0.5 mL diluted phosphoric acid (3 in 10) to the first column (A), then packs above this a mixture of 4 g siliceous earth and ferric chloride-urea reagent. A mixture of 4 g siliceous earth and 2mL of sodium bicarbonate solution (1 in 12) is packed into the second column (B). For analysis, column A is mounted directly above column B. The sample solution is inserted onto column A, allowed to pass into the column, and then washed with 2-40 mL of chloroform. Benzoic acid can be eluted from column B by using a 3 in 100 solution of glacial acetic acid in chloroform. The benzoic acid content then can be determined by a spectrophotometric method such as that described earlier (section 4.5). 

The (S)-amine 23 was synthesized after 1 day and the enzyme was recovered from the reaction by filtration, then washed and reused. The residual amine was extracted from the MTBE solution with dilute phosphoric acid (pH 2.9-4.4). The aqueous extract was concentrated to give a phosphate salt of the (S)-sec-butylamine with 99.7%. This was followed by a crystallization procedure in ethanol to give 99.8% and 50% yield. 

This liquid is evaporated on a water-bath to about 60-70 c.c. and transferred to a separating funnel, where it is acidified with 10 c.c. of dilute phosphoric acid (1 3) and shaken vigorously with about 100 c.c. of a mixture in equal volumes of ether and benzene. When the two layers have separated well, the lower aqueous liquid is run off into a flask. By... 

The liquid thus obtained is filtered into a separating funnel, acidified with dilute phosphoric acid and shaken vigorously with an equal volume of ether. The procedure described above is followed, the extraction being repeated two or three times and the united ethereal liquids washed by shaking with 3-4 c.c. of water. After removal of the water most of the ether is distilled off and the remainder of the liquid and a few c.c. of the distillate used to rinse out the flask transferred to a tared glass dish and evaporated to dryness at a gentle heat, and the residue weighed. 

The aqueous liquid thus obtained is filtered and acidified with a few drops of dilute phosphoric acid and then repeatedly extracted with 50 c.c. of ether. The united ethereal liquids are washed with two quantities of 2-3 c.c. of water, as indicated above, and then filtered through a small dry filter into a tared glass dish and, together with the few c.c. of ether used to wash the filter, evaporated on a water-bath at a gentle heat and the residue weighed. 

Synergistic extraction, in the system DEHPA and TOPO, is quite interesting for its ability to extract uranium from high concentrations of phosphoric acid (38). This finds application in the recovery of uranium from dilute phosphoric acid medium in... 

Color reagent Dissolve 10 g sulfanilamide in dilute phosphoric acid solution (100 mL 85% H3P04 in 800 mL water). Add 1 g AA1-naphthyl) ethylenedi-amine dihydrochloride into this solution. Mix well and dilute to 1 L. 

The absence of synergism in the extraction of U(IV) from aqueous phosphoric acid medium by HDEHP-TOPO was assumed165 as due to the coordination saturation of U(IV) in its complex with HDEHP. However, H2MEHP-B combinations have been used175 for the extraction of U(IV) from dilute phosphoric acid where the synergism observed was inferred to be due to the extraction of U(Hgn 4)MEHP4n) B where B = TOPO or DBBP. 

Mobile Phase Dissolve 250 mg of dibasic sodium phosphate in 250 mL of water and adjust with dilute phosphoric acid (1 in 3) to a... 

The synthesis of a MeAPO molecular sieve typically uses an aqueous reaction mixture formed by combining a dissolved form of the divalent metal, orthophosphor1c acid, a reactive alumina, and an amine or quaternary ammonium templatlng agent (R>. The metal Is typically Introduced as the acetate or sulfate salt, or as the metal oxide dissolved In dilute phosphoric acid. A synthesis mixture Is prepared In one of two ways ... 

Enriched Superphosphate. This product, which is also referred to as double superphosphate, is essentially a mixture of SSP and TSP, usually made by acidulation of phosphate rock with a mixture of sulfuric and phosphoric acids. The desired concentration of mixed acid can be obtained by mixing concentrated sulfuric acid (93 or 98% H2S04) with dilute phosphoric acid (30%) thus avoiding the need for concentrating the latter. Production processes and equipment are about the same as for SSP20... 

Trinitropyridine-N-oxide is produced through a cyclical reaction of potassium salt of 2,2-dinitroethanol in diluted phosphoric acid. 

Transfer 20 mL of sample into a 500-mL separator, add a solution of 20 g of sodium hydroxide in 50 mL of water, stopper the separator, and wrap it securely in a towel for protection against the heat of the reaction. Shake the mixture vigorously for about 5 min, cautiously opening the stopcock from time to time to permit the escape of air. Continue shaking the mixture vigorously until a homogeneous liquid results, then distill, and collect about 25 mL of the distillate. Add 1 drop of dilute phosphoric acid (1 20) and 1 drop of a 1 20 solution of potassium permanganate to 1 drop of the distillate. Mix, allow to stand for 1 min, and add, drop wise, a 1 20 solution of sodium bisulfite until the color disappears. If a brown color remains, add 1 drop of the dilute phosphoric acid. Add to the colorless solution 5 mL of a freshly prepared 1 2000 solution of chromotropic acid in 75% sulfuric acid, and heat on a steam bath for 10 min at 60°. No violet color appears. 

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