Uses of Granite

Granite is most commonly used in applications where physical stability, durability and strength in a mildly acid environment are required. Historical uses of granite as a chemically resistant masonry include its use as flooring in places where "oil of vitriol" (sulfuric acid) was made. In the nineteenth century, granite blocks hollowed out to form tubs were employed by steel wire companies to hold dilute HCI baths for pickling off mill scale from the wire. Some of these tubs are still in use today. 

Other important uses of stannic oxide are as a putty powder for polishing marble, granite, glass, and plastic lenses and as a catalyst. The most widely used heterogeneous tin catalysts are those based on binary oxide systems with stannic oxide for use in organic oxidation reactions. The tin—antimony oxide system is particularly selective in the oxidation and ammoxidation of propylene to acrolein, acryHc acid, and acrylonitrile. Research has been conducted for many years on the catalytic properties of stannic oxide and its effectiveness in catalyzing the oxidation of carbon monoxide at below 150°C has been described (25). 

Determine the range of velocities over which a bed of granite particles (SG = 4) would be fluidized using... 

Age column is given in years, rock column is portion of rock used in a foundation, fireplace or wall in square feet, height of ceiling in ieet. Area is in square feet. Blanks in furnace column indicate no use of furnace, tightness A is average, T is tight, D is drafty, as stated by the homeowner, soil column shows soil from granite bedrock in a foundation, fireplace or wall. Water column is radon concentration in pCi/1. 

Indian workers have advocated the use of molasses in a polymerized form in road-making, either by direct application to a macadamized road surface or by the preparation of a molasses-bitumen composition with which granite chips may be surfaced prior to their use as road material. Hukeri suggests the spreading of diluted molasses followed by sand over a road surface and claims that the surface remains dust-free throughout the dry season. Again, Sen and Frehi make a mixture of... 

Figure 19. Stamp Mill for Making Black Powder. (Courtesy National Fireworks Company and the Boston Globe.) This mill, which makes powder for use in the manufacture of fireworks, consists of a single block of granite in which three deep cup-shaped cavities have been cut. The stamps which operate in these cups are supplied at their lower ends with cylindrical blocks of wood, sections cut from the trunk of a hornbeam tree. These are replaced when worn out. The powder from the mill is called meal powder and is used as such in the manufacture of fireworks. Also it is moistened slightly with water and rubbed through sieves to form granular gunpowder for use in making rockets, Roman candles, aerial bombshells, and other artifices.

Most halloysite appears to be the result of supergene processes and, as noted by Ross and Kerr (1934), leaching by sulphuric acid, produced by the alteration of pyrite, appears to be one of the more common weathering processes. Alunite is commonly associated with halloysite (Ross and Kerr, 1934 Swineford et al., 1954). Sulphuric acid is commonly used to dissolve ilmenite in the manufacture of Ti02 (Willets and Marchett), 1958). It is possible that in nature it serves the same purpose. In the alteration of granitic rocks and pegmatites, feldspar is more likely to alter to halloysite... 

Substantial changes have also been made in the layout of the book in particular, new sections have been added describing the textural and structural particulars of the BIF, the chemical composition of the rocks and minerals and their stability in the face of granitization. We considered it advisable to give an appendix summarizing the thermodynamic values used in the calculations, with briefly stated reasons for choosing them (for the... 

Three different filled PMMA were used. One contains 62 wt% of silica (Si02,10-100 p.m), the other 71 wt% of granite (100-1000 p.m) and the third contains 67% of alnminium trihydroxide (A1(0H)3, ATH). For the pyrolysis, the laboratory-scale linidized plant (Figure 25.1) was used and for two runs the pilot plant with a capacity of 10-50 kg/h feeding rate (Ham-bnrg Process)... 

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