US1430085A - Process of treating biotite - Google Patents

Description

ing books,

Patented Sept. 26, 1922.

UNITED STATES JAMES KEETH; OF SPOKANE, WASHINGTON.

PROCESS OF TREATING BIOTITE.

No Drawing.

To all 107mm it may concern:

Be it known that I, JAMES Knn'rrr, a citi zen of the United States, residing at Spokane, in Spokane County, and the State of Vashington. have invented certain new and useful Improvements in a Process of Treating Biotite. of which the following is a specification.

My present invention relates to an improved process of treating biotite or black mica one of the members of the group of mica minerals, characterized as a silicate of aluminum and iron with magnesium and potassium forming component parts thereof.

By experiment, careful study, analysis, and practical application of the steps of the following process, I have discovered and produced a material of especially high commercial value for purposes of electric and heat insulation, and because of its heat resisting qualities and lubrication may be used in packings for journals, etc., and in addition is readily adapted for decorative purposes when utilized with fancy paints, coating ornamental tiles, and also for coating wall papers.

The process as hereinafter described contemplates the hydration and calcining of the raw material or ore as brought from the mine, and I have herein set forth one complete example of the physical embodiment of my invention which carries out the steps of my process according to the best mode I have thus far devised for the practical application of the principles ,of my invention. The resulting finished product is well adapted for the uses above indicated and may be applied and employed in many antll various other relations than those specifiec.

In mining the raw material, the mineral is found deposited in sheets or layers formthe layers possessing a smooth somewhat greasy appearance, of a dark brownish color, and possessing approximately the specific gravity of ordinary rock. The books of biotite as thus mined are in the form of lumps of mineral-of various sizes and constituted by laminations or closely adhering sheets or leaves, and these lumps or books assume various shapes or forms, some thin and fiat with irregular outlines. and others of greater thickness and more regular in outline, but all possessing the characteristic of laminated adhering sheets or leaves.

The raw material thus mined in subjected Application filed April 12, 1921. Serial No. 460,827.

to the process of dehydrating and burning under heat ranging through various degrees depending upon the requirements of the resulting product.

As an exemplification of the process of treating the mineral, I take the books of biotite as above described and place them in a heating furnace. suitable equipped for the purpose, the quantity of raw material depending upon the size of the furnace. The intensity of the heat to which the material is thus subjected may be varied for producing different characteristics in the resulting product. I have found that by subjecting the material to approximately a heat of 350 degrees F., the dehydrated and burnt material is increased or expanded in size,

i. e., the books or lumps of material retain their original individual body formations as integral elements. but the size is increased and the form or shape may vary from the original. The product thus attained retains its laminated or sheet formation. its specific gravity is decreased and its color ischanged to a shiny light brown or bronze shade.

By increasing the temperature of the heat in the furnace to say seven hundred degrees F. and permitting the application of this heat to approximately a period of seven minutes time. the size of the product is expanded and closely approaches ten times the original size. Thus for example I take a mass of lumps in quantity and size approximating a cubic foot and weighing about 100 lbs. After subjecting these lumps to a temperature of 700' degrees F. for a period of about seven minutes, the cubical,

size of the mass has expanded to ten times the original size, and of course each individual lump has been expanded approximately ten times its original size. The specific gravity of the material has been greatly reduced, and the resulting mass is made up of lofty constituents still retaining their laminated form and although of increased size yet maintaining somewhat a resemblance to the original shape. The individual pieces may be compared in weight to a similar size piece of cork. The color has been further changed from that resulting when the material is subjected to a les intense heat as above described, and now possesses a gold bronze shade or hue of much lighter appearance than the material when-subjected to a less heat. The ex:

absorbent of water. Its brittleness or fragility renders it easy and facile in pulverization, and the mass of lumps may thus be ground to a fine flaky powder. And in the process of treating the material, this step of pulverizing or comminuting the lumps into powder is utilized in order that the resulting powder may be incorporated as a pigment in paints for decorative purposes. Thus the raw material is burnt, expanded,

and powdered and in this condition is readily" adaptable for the commercial uses-above described.

Before comminuting the lofted lumps thus produced, they may be utilized as filling material for difierent purposes, .thus

providing a light, resilient, lumpy mass suitable for packing or filling purposes. The powdered or comminuted burnt biotite may be incorporated, if desired with other components, and used in the electrical industry, where an insulating, non-inflammable, resistant material is necessary and the composition ma be fashioned into sheets, washers,

tubes an other electrical fittings and appliances. Or the powdered-burnt biotite may be used as a powder in various commercial forms where such an element is required, and in addition the powder may be used for decoration in wall papers, ornamental tiles, &c. Because of its heat resisting qualities the burnt and expanded biotite may be adapted and fashioned as packings for journal boxes of railway cars or used as a filler in pipe and boiler coverings, and the powdered biotite may be used in fire proof and paint coverings.

Having thus fully described my invention, what I claim and desire to secure by Letters Patent is The process of treating biotite which consists in subjecting the books to approx-' imately a temperature of 700 F. whereby the books are dehydrated and lofted, and

subsequently comminuting the dehydrated and lofted books.

In testimony whereof I afiix my signature.

JAMES KEETH.