Dry product

The oxime is freely soluble in water and in most organic liquids. Recrystallise the crude dry product from a minimum of 60-80 petrol or (less suitably) cyclohexane for this purpose first determine approximately, by means of a small-scale test-tube experiment, the minimum proportion of the hot solvent required to dissolve the oxime from about 0-5 g. of the crude material. Then place the bulk of the crude product in a small (100 ml.) round-bottomed or conical flask fitted with a reflux water-condenser, add the required amount of the solvent and boil the mixture on a water-bath. Then turn out the gas, and quickly filter the hot mixture through a fluted filter-paper into a conical flask the sodium chloride remains on the filter, whilst the filtrate on cooling in ice-water deposits the acetoxime as colourless crystals. These, when filtered anddried (either by pressing between drying-paper or by placing in an atmospheric desiccator) have m.p. 60 . Acetoxime sublimes rather readily when exposed to the air, and rapidly when warmed or when placed in a vacuum. Hence the necessity for an atmospheric desiccator for drying purposes. 

Filter the crystals at the pump, wash them with water, and drain well. To save time, the product may be recrystallised directly from an ethanol-water mixture (1 2 by vol.), and obtained as colourless crystals, m.p. 68°. Alternatively, the crude product can be dried in a desiccator (yield of dry product, I-9-2 0 g., m.p. 65-67°) and recrystallised from petroleum (b.p. 60-80°), and obtained as needles, m.p. 68°. 

Dissolve 10 g. of chloro- 2,4-dinitrobenzenet in 50 ml. of dioxan in a 250 ml. conical flask. Dilute 8 ml. of hydrazine hydrate with an equal volume of water and add this slowly with shaking to the dioxan solution, keeping the temperature between zo " and 25°. Heat under reflux for 10 minutes to complete the reaction and then add 5 ml. of ethanol and heat again for 5 minutes. Cool and filter oflF the orange 2,4-dinitrophenylhydra-zine. Recrystallise the dry product from ethyl acetate m.p. 200° (decomp.). Yield, 7 g. 

Fit securely to the lower end of the condenser (as a receiver) a Buchner flask, the side-tube carrying a piece of rubber tubing which falls well below the level of the bench. Steam-distil the ethereal mixture for about 30 minutes discard the distillate, which contains the ether, possibly a trace of unchanged ethyl benzoate, and also any biphenyl, CeHs CgHs, which has been formed. The residue in the flask contains the triphenyl carbinol, which solidifies when the liquid is cooled. Filter this residual product at the pump, wash the triphenyl-carbinol thoroughly with water, drain, and then dry by pressing between several layers of thick drying-paper. Yield of crude dry product, 8 g. The triphenyl-carbinol can be recrystallised from methylated spirit (yield, 6 g.), or, if quite dry, from benzene, and so obtained as colourless crystals, m.p. 162. ... 

Proceed as in (A), using 50 ml. of ethanol, with boiling for 20 minutes. The quinoxaline (III) crystallises readily during the boiling. Cool the mixture, filter off the quinoxaline, and wash it with ethanol. The dry product, of m.p. 220 225", weighs 1 3 g. Recrystallise the quinoxaline from chloroform or acetic acid pale yellow crystals, m.p. 226°. Yield, 0 9-ro g. 

Cool the reaction-solution, and pour it into a 250 ml. beaker, washing out the flask with ca. 50 ml. of water into the beaker. Chill the solution in ice-water and add dilute hydrochloric acid with stirring until the solution is just acid when spotted externally on to Congo Red paper. The arsinic acid rapidly separates. Filter at the pump, wash well with water and drain. (Yield of crude dry product, 7-5-8 o g. m.p. 200-203°.)... 

Filter the dried product through a fluted filter paper or a small cotton wool plug supported in a funnel into a dry 50 ml. distilling flask, and distil on a wire gauze or from an air bath (Fig. 11, 5, 3). Collect the fraction, b.p. 100-103°. The yield of n-butyl bromide is 18-19 g. 

I) When working with larger quantities of material, it is more convenient (and a better yield is obtained) to purify the air-dried product by distillation under diminished pressure. Use the apparatus pictured in Fig. II, 19, 4, and add a few fragments of porous porcelain to the solid. No air inlet can be employed to prevent bumping since this may lead to explosive decomposition. Collect the pure m-nitrophenol at I60-I65°/I2 mm. always allow the flask to cool before admitting air otherwise the residue may decompose with explosive violence. The recovery is over 90 per cent, of the pure m-nitroplienol. 

In a 500 ml. bolt-head flask provided with a thermometer (reaching almost to the bottom) and a calcium chloride (or cotton wool) guard tube, place 100 g. of a-bromo-wo-valerj l bromide and 50 g. of dry, finely-divided urea. Start the reaction by warming the flask on a water bath the temperature soon rises to about 80°. Maintain this temperature for about 3 horns the mass will liquefy and then resolidify. Transfer the sticky reaction product to a large beaker containing saturated sodium bicarbonate solution, stir mechanically and add more saturated sodium bicarbonate solution in small quantities until effervescence ceases. Filter at the pump, suck as dry as possible and dry the crude bromural upon filter paper in the air. RecrystaUise the dry product from toluene. Alternatively, recrystaUise the moist product from hot water (ca. 700 ml.). The yield of pure brommal, m.p. 154-155°, is 28 g. 

Before polyacrylamides are sold, the amount of residual acrylamide is determined. In one method, the monomer is extracted from the polymer and the acrylamide content is determined by hplc (153). A second method is based on analysis by cationic exchange chromatography (154). For dry products the particle si2e distribution can be quickly determined by use of a shaker and a series of test sieves. Batches with small particles can present a dust ha2ard. The percentage of insoluble material is determined in both dry and emulsion products. 

The reduction of water limits mold formation, but only slightly affects the aroma or pungency. The dried product maintains its character and pound for pound is stronger in aroma and flavor than the fresh spice, since a nonessential component has been substantially removed. In areas where a spice is grown, the same product that is dried for storage and shipment is often used fresh for flavoring. 

The importance of hydrolysis potential, ie, whether moisture or water is present, is illustrated by the following example. In the normal dermal toxicity test, namely dry product on dry animal skin, sodium borohydride was found to be nontoxic under the classification of the Federal Hazardous Substances Act. Furthermore, it was not a skin sensitizer. But on moist skin, severe irritation and bums resulted. 

Seaweeds. The eadiest successful manufacture of iodine started in 1817 using certain varieties of seaweeds. The seaweed was dried, burned, and the ash lixiviated to obtain iodine and potassium and sodium salts. The first process used was known as the kelp, or native, process. The name kelp, initially apphed to the ash of the seaweed, has been extended to include the seaweed itself. About 20 t of fresh seaweed was used to produce 5 t of air-dried product containing a mean of 0.38 wt % iodine in the form of iodides of alkah metals. The ash obtained after burning the dried seaweed contains about 1.5 wt % iodine. Chemical separation of the iodine was performed by lixiviation of the burned kelp, followed by soHd-Hquid separation and water evaporation. After separating sodium and potassium chloride, and sodium carbonate, the mother Hquor containing iodine as iodide was treated with sulfuric acid and manganese dioxide to oxidize the iodide to free iodine, which was sublimed and condensed in earthenware pipes (57). 

DR Processes Under Development. The 1990s have seen continuous evolution of direct reduction technology. Short-term development work is focusing on direct reduction processes that can use lower cost iron oxide fines as a feed material. Use of fines can represent a 20 30/1 (20%) savings in DRI production cost compared to use of pehets or lump ore. Some examples of these processes include FASTMET, Iron Carbide, CIRCOFER, and an improved version of the EIOR process. 

Over 95% of the world s DRI production is consumed in electric arc furnace steelmaking. The remaining 5% is spHt among blast furnaces, oxygen steelmaking, foundries, and ladle metallurgy (qv) faciUties. 

Mineral Mining Corp. Kershaw, S.C. 22,675 dry product is sericite for paint industry... 

Dmm-dried products ate more affected by heat than spray-dried products. Drying ia a vacuum chamber decreases the temperature and thus the heat effect on the product, although the atmospheric dryers are used more widely. 

Dmm-dried products, mostly nonfat, make up only 5—10% of dried milk products. Because of the high temperature and longer contact time, considerable proteia denaturation occurs. Dmm-dried products ate identified as high heat dry milk and as such have a lower solubHity iadex, lower proteia nitrogen content, and a darker color. 

Agglomeration. The process of treating dried products, particularly nonfat products, ia order to iacrease speed and abHity to reconstitute those products, is known as instantizing or agglomeration. Particles are agglomerated iato larger particles which dissolve more easHy than smaH particles. In... 

Casein hydrolyzates are produced from dried casein. With appropriate heat treatment and the addition of alkaHes and enzymes, digestion proceeds. FoUowing pasteurization, evaporation (qv), and spray drying, a dried product of 2—4% is obtained. Many so-called nondairy products such as coffee cream, topping, and icings utilize caseinates (see Dairy SUBSTITUTES). In addition to fulfilling a nutritional role, the caseinates impart creaminess, firmness, smoothness, and consistency of products. Imitation meats and soups use caseinates as an extender and to improve moistness and smoothness. 

The U.S. domestic capacity of ammonium perchlorate is roughly estimated at 31,250 t/yr. The actual production varies, based on the requirements for soHd propellants. The 1994 production ran at about 11,200 t/yr, 36% of name plate capacity. Environmental effects of the decomposition products, which result from using soHd rocket motors based on ammonium perchlorate-containing propellants, are expected to keep increasing pubHc pressure until consumption is reduced and alternatives are developed. The 1995 price of ammonium perchlorate is in the range of 1.05/kg. Approximately 450 t/yr of NH ClO -equivalent cell Hquor is sold to produce magnesium and lithium perchlorate for use in the production of batteries (113). Total U.S. domestic sales and exports for sodium perchlorate are about 900 t/yr. In 1995, a solution containing 64% NaClO was priced at ca 1.00/kg dry product was also available at 1.21/kg. 

The clear supernatant solution is decanted and sold in Hquid form or concentrated to approximately 61.5 ° Bh and then allowed to soHdify to form blocks that are cmshed, ground, and graded. A typical analysis for the dry product is total A117.0—17.5% Fe202 <0.5% water of composition 42—43% insoluble <1.0%. Liquid alum contains 7.5—8.5% Al O. At concentrations >8.5% AI2O2, crystallisation of the solution may occur. 

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