Mill, ball colloid

Milling (ball, colloid,. ..) in order to increase the surface contact of the components of the composite catalyst... 

All ball, pebble, rod and cone mills, edge runner mills, tube mills, vibration mills and some ring ball mills may be used wet or dry except where stated. The perl mills, sand mills and colloid mills may be used for wet milling only. 

The following equipment are in regular use for drygrinding pharmaceutical materials edge- and end-runner mills, hammer mills, pin mills, ball mills, vibratory mills, fluid energy mills, colloid mills, and roller mills. 

Basic Operations in Paint Manufacture Oil Absorption and the Milling Process Bulk Properties of Paints Types of Mills for Paint Manufacture Stone and Colloid Mills Roller Mills Ball and Pebble Mills Sand Mills... 

Agitator Ball Mill A machine for the comminution, or size reduction, of minerals or other materials. Such machines crush the input material by wet grinding in a cylindrical rotating bin containing grinding balls. Colloidal size particles can be produced with these mills. 

Artificial graphite has been ground in ball mills in closed circuit with air classifiers. For lubricants the graphite is ground wet in a paste in which water is eventually replaced by oil. The colloid mih is used for production of graphite paint. 

A colorless, colloidal precipitate was formed and stirred thoroughly for about 15 minutes, whereupon it was filtered by suction. The raw product thus obtained was washed with water until It contained only about Va% water-soluble salts. After drying for 12 hours In a vacuum apparatus at 60°C and under a pressure of 12 mm Hg, the product had the form of hard pieces. The pieces were comminuted to powder in a ball mill and the powder was passed through a sieve (3,600 meshes per cm ). The small residue on the sieve was again pulverized and passed through the same sieve. The yield was 870 g, or 99% of theoretical, calculated on the assumed formula... 

Kaye, An Electron Microscope Method for the Determination of the Particle Size Distribution and Particle Shape of Colloidal and Ball-Milled Lead Azide , PATR 2133 (1955) 25a) A.T. 

W.J. Mead (Ed.), Balling devices, Briquet machines, Grinding, Mills colloid, Mills roller, Screening, in Encyclopedia of Chemical Process Equipment, Reinhold, New York, 1964. 

In industrial and laboratory settings the subdivision process more commonly involves the comminution of large particles or aggregates into smaller sizes, either dry with subsequent dispersion (size reduction to the order of a few pm) or directly in a slurry (size reduction to as small as a few tenths of pm). Examples of comminution machines include agitator ball mills, colloid mills, cutting mills, disk mills, homogenizers, jet mills, mechanical impact mills, ring-roller mills, and roll crushers. 

Figure 7.7 Examples of (a) a colloid mill and (b) a ball mill used for the preparation of suspensions by the dispersion method. Figure (a) courtesy Premier Mill, Reading, PA Figure (b) courtesy Paul O. Abbe Inc., Little Falls, NJ.

Refs l)K.Bergl J.Reitstotter, GerP 541468 (1926) Si CA 26, 2320 (1932) (Colloidal expl prepd by grinding its ingredients to colloidal fineness in a slowly rotating ball mill) 2)A,... 

Extraction of protein requires breaking the cell wall to release the cytoplasmic contents. This can be achieved by high speed ball or colloid mills or by high pressure (50—60 Mpa) extmsion. Protein is extracted by alkaline treatment followed by precipitation after enzymatic hydrolysis of nucleic acids. Although the protein can be spim into fibers or texturized, such products are more expensive than those derived from soybean and there is no market for them. 

Steurer and Hess (17) have already calculated that the kinetic energy from the impact of balls (in a colloid ball mill used by Staudingcr - Vol. II, p. 276) on cellulose fibres should be sufficient to rupture covalent bonds in cellulose such as C-C, C-0. Breaking such bonds requires energy of the order 80 -90 kcal. This statement was substantiated by Swedish authors [18] who found experimentally that the covalent bonds in cellulose, as above, can be ruptured by mechanical action (in an agate ball mill). It has been known since 1895/96. thanks to the work of Bruley (Vol. II, p, 276), that pulping nitrocellulose reduces the viscosity of its solutions, but only now the experimental facts can be explained in terms of breaking the covalent bonds. This was done by T. Urbanski... 

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