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Mortar crystallization

Triturate 20 g. of dry o-toluidine hydrochloride and 35 5 g. of powdered iodine in a mortar and then grind in 17 -5 g. of precipitated calcium carbonate. Transfer the mixture to a conical flask, and add 100 ml. of distilled water with vigorous shaking of the flask. Allow the mixture to stand for 45 minutes with occasional agitation, then heat gradually to 60-70° for 5 minutes, and cool. Transfer the contents of the flask to a separatory funnel, extract the base with three 80 ml. portions of ether, diy the extract with anhydrous calcium chloride or magnesium sulphate, and remove the excess of solvent. The crude 5-iodo-2-aminotoluene separates in dark crystals. The yield is 32 g. Recrystallise from 50 per cent, alcohol nearly white crystals, m.p. 87°, are obtained. [Pg.648]

Sodium salt of eosin. Grind together in a mortar 12 g. of eosin with 2 g. of anhydrous sodium carbonate. Transfer the mixture to a 250 ml. conical flask, moisten it with 10 ml. of rectified spirit, add 10 ml. of water and warm on a water bath, with stirring, until the evolution of carbon dioxide ceases. Add 50 ml. of ethyl alcohol, heat to boiling, and filter the hot solution through a fluted filter paper (supported in a short-stemmed funnel) into a beaker, and allow to stand overnight. Filter ofiF the browiiish-red crystals of sodium eosin, wash with a little alcohol, and dry. The yield is 10 g. [Pg.986]

The octyl hydrogen phthalate is filtered, washed with water, ground thoroughly with water in a mortar and finally filtered and dried. For complete purification it may be crystallized either from petroleum ether (b.p. 60-70°) or glacial acetic acid from which it separates as needles melting at 55°. The crude material, however, is perfectly satisfactory for the following experiments. The yield is nearly quantitative if the ec.-octyl alcohol is pure (Note 2). [Pg.69]

The technique of trituration is frequently useful. The organic product is stripped of solvent and the oily residue is placed in a mortar and covered with a layer of a solvent in which it is only slightly soluble. The mass is ground with a pestle mixing in the solvent as thoroughly as possible. In favorable cases, the solvent removes traces of impurities that may be inhibiting crystallization, and grinding action induces crystallization. [Pg.182]

The aqueous solution is then concentrated to dryness at an outside temperature of 40° to 45°C and at low pressure. The residue, obtained by drying in a vacuum at 40° to 45°C is triturated in a mortar with ethyl ether and, after filtration, is extracted with 3,400 ml boiling absolute ethanol. The ethanol extract is separated from the undissolved part by filtration, cooled and the product which crystallizes by cooling is filtered and dried at 40°C in a vacuum. In that manner the disodium (4,4 -disulfoxy-diphenyl)-(2-pyridyl)-methane bi-hydrate is obtained, which takes the form of a white solid, according to U.S. Patent 3,528,986. [Pg.1233]

For example, the difference between the monoclinic CaC2 phases is the presence of only one type of acetylide ion in phase II and two distinct C2 species in phase III, as concluded from their crystal structures and from C-NMR studies (Fig. 8.3) [8]. The transformation between phases II and III is induced by heating phase II above 150°C until the metastable phase. III, is formed. Phase III remains stable even when being cooled down to room temperature. However, when the metastable phase III is ground in a mortar at room temperature, it transforms back into phase II. [Pg.124]

Microstructure is also affected by water content. The 1 16 mortar contained hexagonal plates, while the 1 8 mortar had an ellipsoidal morphology. The 1 5 mortar when prepared at — 5 °C developed striking, well-formed, needle-like crystals (Figure 6.9). [Pg.231]

For the DRIFTS study, the Nafion-Ti02 slurries were sonicated for 2 hours, dried at ambient conditions for 5 hr, and ground with a pestle and mortar until a fine powder catalyst was formed. 30 mg of the resulting catalysts were placed on top of 80 mg of inert CaF2 powder (325 mesh, Alfa Aesar) in a DRIFTS cell s sample holder. The sample holder was enclosed by a dome with two IR transparent ZnSe windows and a third CaF2 window for UV illumination. For the ATR study, the Nafion-Ti02 slurries, which were sonicated for two hours, were cast directly on the surface of the ATR ZnSe crystal to form a continuous solid film. The films were enclosed with a stainless steel cover equipped with a CaF2 window for UV illumination. [Pg.464]

Irradiation of (+ )-crystals of 96 with a 400 W high-pressure Hg-lamp, with occasional grinding with an agate mortar and pestle for 40 h at room temperature gave ( + )-97 of 93 % ee in 74 % yield. Irradiation of (—)-crystals of 96 under the same conditions gave (—)-97 of 93 % ec in 75% yield48. Purification to 100% ee can easily be achieved by recrystallization from benzene. Although the photochemical conversion of 96 into 97 on irradiation in the solid state has been reported, enantioselectivity of the reaction has not been discussed 441. [Pg.243]

Plaster of Paris has long been used as a casting material, a cement, and a mortar. If mixed with water, plaster of Paris forms a very soft and pliable mixture. After a very short time, lasting only 5-8 minutes, the wet, pliable mixture sets, that is, it hardens into a stable, firm solid. The setting process entails the incorporation of water molecules (a process known as hydration) into the calcium sulfate hemihydrate and the consequent formation and crystallization of hydrated sulfate of calcium. In other words, when water is added to plaster of Paris, the two combine, again forming gypsum, which soon crystallizes into a hard solid mass ... [Pg.175]

ABSTRACT The aim of this study was to test portable infrared spectroscopy for non-destructive analysis of ancient construction mortar. Mortar samples from the House of the Vestals, in Pompeii, Italy, were initially examined with traditional analytical techniques, including X-ray fluorescence, X-ray diffraction and thin section analysis. These techniques were used to establish mineralogical and chemical profiles of the samples and to verify the results of experimental field methods. Results showed the lime-based binder was composed of calcite, and the volcanic sand aggregate contained clinopyroxene, plagioclase, sanidine and olivine crystals. [Pg.303]


See other pages where Mortar crystallization is mentioned: [Pg.143]    [Pg.259]    [Pg.130]    [Pg.452]    [Pg.485]    [Pg.550]    [Pg.551]    [Pg.774]    [Pg.784]    [Pg.798]    [Pg.823]    [Pg.967]    [Pg.1012]    [Pg.494]    [Pg.95]    [Pg.485]    [Pg.138]    [Pg.376]    [Pg.727]    [Pg.75]    [Pg.130]    [Pg.452]    [Pg.485]    [Pg.550]    [Pg.551]    [Pg.774]    [Pg.784]    [Pg.798]    [Pg.823]    [Pg.967]    [Pg.1239]    [Pg.294]    [Pg.267]    [Pg.148]    [Pg.157]    [Pg.25]    [Pg.132]    [Pg.63]   
See also in sourсe #XX -- [ Pg.256 ]




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