US1402256A - Titanium complexes and method for producing same - Google Patents

Description

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HENRY H. BUGKMAN, OF JACKSONVILLE,

TITANIUM COMPLEXES AND METHOD FOR PRODUCING SAME.

No Drawing.

is a specification.

My present invention relates to artificial titanium complexes, i. e., materials wholly or partially composed of compounds of titanium precipitated from solutions. These complexes may consist substantially or entirely of a compound of titanium, or a mixture of compounds of titanium, or a mixture of titanium compounds and compounds of other elements. My invention has for its objects new and useful titanium complexes and methods for producing these.

I have discovered that the nature of the precipitates which may be produced by the hydrolysis of titanium salt solutions is profoundly modified by high temperatures, and to a lesser degree by high pressures. Upon this discovery of mine rests my. present invention.

It has been well known for a long time that a weak acid solution of a titanium salt, when sutliciently dilute, could be made to throw out a titanium complex by heating the soluspeed of these reactions, higher temperatures should be employed if possible. Higher temperatures can be utilized only by two niethods, i. e., by'increasing the concentration of the solution and thereby its boilingpoint, and by increasing the pressure over the solution. The former method is subject to only limited application because hydrolysis of a titanium salt in solution will not takeplace below the boiling point of the solution after the concentration reaches a certain point. Knowing these facts, both from theoretical knowledge and practical experimental expe- Specification of Letters Patent.

Patented Jan. 3, 1922..

Application filed November 15, 1920. Serial No. 424,182.

lieve that I am the first to have carried out such an exploration with titanium salt solutions and that I am'the first to have discovered and recognized that the nature of the precipitate resulting from this hydrolysis is fundamentally modified at high temperatures and pressures. Whereas at temperatures in the neighborhood of 100 degrees centigrade, the hydrolyt-ic precipitates formed are usually slimy, and when dried are usually horny, tough and of little pigment-' ing power,- on the other hand at temperatures about and abovelTO degrees centigrade the same solution will yield a precipitate which is dense, and which dries to a smooth, fine white powder, having remarkable pigme'nting powers. I am unaware of the exact chemical composition of this new precipitate of mine, but its behavior indicates that it is' at least largely composed of some higher acid of titanium, possibly a compound in which titanium is hexavalent, not heretofore known or produced, mixed probably with other hydrolytic titanium products. Its bulk, texture, color, hiding power and general behavior denote it as at least physically a distinct new substance not heretofore known or produced.

In addition to the new and useful properties of my new material, the amount of yield '85 from a given solution at these high temperatures and pressures is very nearly double that obtained at temperatures and atmospheric pressure heretofore used.

In order to more clearly illustrate the nature of my invention and in order to more fully describe certain of its advantages, I will give one specific example of its practice, although it will be readily understood that my invention is in no way limited to or by the example given.

I took a given quantity of a concentrated solution of titanium sulphate, carrying a. small amount of free sulphuric acid. This I divided into two equal parts, and proceeded as follows :One part I diluted with one and one half times its own volume of water and heated at 100 degrees centigrade for seven hours. At the end of that time I filtered and. air-dried the precipitate. It weighed 190 grams. .It was of a tough, horny, translucent appearance and even when finely powdered had only a slight hldin 'power.. Apparently it was composed chlefiy of meta titanic acid. This is the method usually employed heretofore. Pursuin mv new methodwith the other nortion of the solution, for comparison, I proceeded as follows :-I did not dilute the solution, but even added to its acid concentration by adding one to two per cent of its weight in concentrated sulphuric acid. This solution I then placed in a glass-lined steel container which was made gas-tight, and heated it to 185 degrees centigrade and at the corresponding pressure for twenty minutes. I then opened the containerand found that the precipitate was so bulky and abundant that the entire contents of the container were semi-solid and too thick to pour without the addition of water. Water was added, and the solution filtered and the precipitate washed, air-dried and weighed. It weighed 390 grams. The dried precipitate was a pure white, verysmooth, dense and fine powder, with remarkable hiding and pigmenting powers, and superior to any similar complex known to me. I believe it to be composed substantiallyof a higher titanic acid, although its exact chemical composition is not known to me. That it is new and diflerent from any titanium complex heretofore produced is amply denoted by its difierent physical characteristics already mentioned.

My method of heating at high tem eratures under pressure has numerous a vantages. I have discovered that by this means I can employ very much stronger acid solutions than in existing methods, and can thus prevent the precipitation of undesired impurities, notably iron. Furthermore I have discovered that at these high temperatures and pressures hydrolysis awill take place in much more concentrated solutions. As mentioned above, the yield is nearly double that in methods hitherto practised. Since more concentrated solutions can be used, it is unnecessaryto treat such a large amount of solution, thuseifecting a very decided economy. Since stronger acid solutions can be used, the acid remaining at the end of the reaction is more concentrated and hence more valuable to recover than in the case of existing methods. Furthermore, the time required for the hydrolysis is from one fifth to one tenth that required in methods hitherto practised. I have employed my novel method and produced myv new material from a variety of titanium salts in solution, especially from hydrochloric acid solutions, and find it applicable to all titanium salts subject to by, drolysis known to me.

In my researches, I have not only carried out numerous tests and operations with the titanium solutions at high temperatures and simultaneously high pressures, but I have used high pressures and low or moderate temperatures, and I have found as stated above that the effect of high pressure is less marked than is that of high temperature,

barium chloride, barium hydroxide, calcium chloride, calcium hydroxide, phosphoric acid, etc., forming thereby new and superior conliplex co-precipitates with my new materia I find that my new material, either alone, or when precipitated with or upon certain other substances, is excellently suited for a pigment and for mixing with oils and the like to form paints and enamels, and for the manufacture of rubber and linoleum, and for plastics and printers inks, and as a lake pigment, without first being calcined.

I have also found it't-o work exceptionally well when mixed in paints and the like with white and red lead, lithopone, white zinc, zirconium oxide and other pigments, lending to all these its new and valuable properties of hiding and tinting power and comparative inertness to chemical action. I have discovered that my new material and the composite and coprecipitated products madewith it and mentioned above have remarkable and superior hiding and pigmenting power when in the air-dried, uncalcined state, rendering them Well suited to all the above-named purposes. Under certain conditions in each of the above uses, however, I-prefer to calcine my material, either alone or co-precipitated with or upon other substances, and this I doby heating in air to a dull red heat for thirty minutes.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is the following:

1. In the hydrolytic production of precipitates containing titanium complexes, the employment of temperatures higher than the atmospheric boiling point of the solution.

2. In the hydrolytic production of precipitates containing titanium complexes, the step which comprises carrying out the precipitation at temperatures substantially above 100C. simultaneously with pressures above normal atmosphere.

3. In the hydrolytic production of pre cipitates containing titanium complexes the step which consists in heating the solution under pressure substantially above atmosphere.

l. In the production of composite pig- 6. As a new article, the hereinbefore dc scribed uncalcined composite product, comprising atitanium complex associated with barium sulphate and distinguished as consisting essentially of very fine and dense particles produced under temperatures substantially above 100 degrees centigrade, and under pressures substantially above atmosphere;

7. As a new article, the hereinbefore described uncalcined composite product, distinguished as consisting essentially of barium sulphate particles and adhering thereto particles of a titanium complex hydrolyti- ,cally precipitated thereon at temperatures substantially above100 C. and under pressure substantially above atmosphere.

' HENRY H. BUCKMAN.