US1209692A - Binding compound and process of making same. - Google Patents

Description

ARCHIBALD CLAUDE EVANS, OF HAMPTON WIGK AND IE'EIIRGY J'OSIlil MITCHELL, 0F WESTMINSTER, LONDON, ENGLAND.

BINDING COMPOUND AND PROCESS OF MAKING SAME.

N0 Drawing.

To all whom it may concern:

Be it known that we, ARGHIBALD CLAUDE EVANS and PERCY J osii MirroHELL, residing at Hampton Wick, Middlesex, England, and Westminster, London, England, respectivel have invented certain new and useful mprovements in Binding Compounds and Processes of Making Same; and we do hereby declare the following tobe a full, clear, and exact description of the invention, such as will enable others skilled'in the art to which it 'appertains to make and use the same. I

Thisinvention relates to a new and improved binding material for use in briqueting, road making and the like applications and comprises a process for producing same.

Heretofore tar pitch has been thebinding agent or ingredient mostly employed for the purpose of making fuel briquets from coal, and while its use is very effective for such purpose the same is attended by a number of disadvantages. Among these may be mentioned firstly the fact that operatives employed in the process using pitch are subject to pitch cancer, and skin troubles the presence of the phenols in the finished due probably to the presence of phenols or phenol derivatives which escape from the molten compound. A further disadvantage is that in order to obtain the pitch the' tar has to be subjected to a prolonged and therefore costly process of distillation before it will yield a substance that will set to a sulficient hardness when cold. The necessity of carrying out this distillation accounts for product, the .reason being that although these phenols are removed in the earlier stages of distillation it is necessary -to introduce a portion of the first runnings into the i still at the close of the distillation in order to be ableto withdraw the thick pitch which 5 remains, and it is in this way that the phenols are introduced into the product.

Processeshave already been proposed for solidifying tar by heating it in a still to a I temperature not exceeding 360- F. and after cooling adding to it considerable quantities of sulfuric acid, these quantities varying am such Previously known processes in that in i" v .the latter practically the whole of the solidifying is e from a minimum of 3% to a maximum of The present invention differs from ected by means of a considerable Specification of Letters Patent. Patented Deg, 26, 1191108, Application filed September 7, 1915. Serial in. 49,349.

quantity of sulfuric acid, while in the former the solidification is effected principally by the addition of a considerable quantity of carbon, while only an exceedingly small quantity of sulfuric acid is used at the end of the process; it will thus be apparent that the material obtained according to the prescut invention will be of an entirely different tar would yield in the ordinary-way. The

phenols removed in the earlier distillation are not re-introduced into the product and the process also provides means for regulating( the ultimate consistency and binding properties of the finished product.

The invention carried out as follows: The starting out material is preferably coal tar in the condition. in which the same is usually obtained from gas works except that most of the ammonia may have been removed from the tar before use. The tar is distilled at a temperature of 270? in a suitable retort or still. The latter may be of any convenient'type but should be fitted with a man-hole capable of being hermetically closed and should further be provided with a mechanical stirring device. The heating arrangements consist preferably of a furnace provided with the usual fines which should be so arranged that the heat can be shut 011' at any desired moment, so as to ,palpablefomn is now gradually added and stirred into the mass. The reason-why this operation must not be carried out at a temperature above 250 C. is, that as the man- The hole must be opened for the purpose the tar and coal dust would be liable to catch fire if this temperature were exceeded. The coal used should preferably be of high volatile contents and the amount added may be va- .ture raised to a minimum of 270 stirring being continuedthe whole time; the content is kept at that temperature or not lower than that temperature until the added coal or like material begins to soften and give off its volatile contents. As soon as this action starts the heat is immediately shut off and the material is allowed to cool as rapidly as possible to a temperature below 100 0. If desired the material can be pumped into a tank or like vessel for this cooling to take place. At this stage 0.25% to 1.9 0 of sulfuric acid of a preferred strength of 170 Twaddle is gradually added and intimately mixed with the material and if this operation is carried out in a secondtank the latter should be provided with suitable stirring or agitating means. Care must be taken that the temperature of the mixture while the sulfuric acid is being added does not rise above 100 0. nor fall below 49 0. After the acid to its measure has been added and thoroughly stirred in the-hot mass is run off and allowed to cool and solidify in any suitable molds or other receptacles convenient for the purpose.'

In lieu of coal tar, shale oil, or any other similar mineral oil may be used, and in the treatment of the same for the purpose of this invention the light volatile oils are dis tilled off until the residue is of about the same consistency as that of the tar previously referred to at a temperature of 270. 0. after the same has been distilled at that temperature in the manner described. The subsequent manufacture of the compound is identical with that described in the case of coal tar. Also in place ,of sulfuric acid, chlorid of sulfur or other known thickening agent may be employed, but sulfuric acid will generally be found to be preferable, owing to the ease with which it can be procured and owing to the fact that it is less unpleasant to handle than the other known and hitherto used thickening agents.

By the above described means a material is produced which resembles pitch and has similar softening and melting points, while its vaporization point is about 0. higher than that of most of the ordinary commercial medium pitches usually sold for briqueting purposes. The yield of ordinary pitch from-ordinary coal tar is about 5 tons from 10 tons of tar, while accordin to the invention 8 tons and 16 cwt. of binding agent can be roduced from 10 tons of tar. part from the other previously described advantages of this invention it will be seen that a material which solidifies into a pitch like substance which melts and softens at similar temperatures to pitch is obtained without the necessity of carrying the distillation of the tar to anything like the same stage. A further advantage is that the consistency of the final product can be controlled within reasonable limits by the amount of loading material added. It will also be seen that the objectionable addition of the light oils containing phenols which is usual in the ordinary production of pitch is obviated according to this invention and that the finished product is free from or practically free from phenols which pass over during the first distillation.

We claim 1. A process for the manufacture of binding materials for briqueting, road making and the like which includes removing the light oils from coal tar, treating saidtar while hot with finely divided coal dust or hydrocarbon soot, cooling the resulting product to 100 0. and then treating with a small quantity of thickening agent.

2. A process for manufacturing binding materials for briqueting, road making and the like which includes distilling coal tar at a temperature of 270 0. until the light oils have been removed, cooling the product to approximately 250 0., adding finely divided coal dust or hydrocarbon soot, stirring the mixture and heating to a minimum temperature of 27 0 0. until the volatile matter begins to pass off from the added material, cooling the mixture to 100 0. nd adding a small quantity of sulfuric acid or a specified equivalent thickening agent.

3. A process for the manufacture of binding materials for briqueting, road making and the like which includes removing the light oils from shale oil distillate or its specified equivalent, treating the same while hot with finely divided coal dust or its specified equivalent, cooling the mixture to 100 0., and adding a small quantity of sulfuric acid or its specified equivalent thickening agent.

4:. A process for the manufacture of binding materials for briqueting, road making and the like which includes distilling shale oil distillate or its specified equivalent at a temperature of 270 0. until the light oils have been removed, cooling the product to approximately 250 0., adding finely divided coal dust or its specified equivalent,

thoroughly stirring the mixture and heating the same to a minimum temperature of 27 0 0., maintaining the temperature of 270 0.

road making and the like consisting of the residue from coal tar after the light oils have been removed, said residue being thickened with coal dust or its specified equivalent and a small quantity of sulfuric acid or its specified equivalent. A

In testimony whereof we aflix our signatures in presence of two witnesses.

ARCHIBALD CLAUDE EVANS. PERCY JOSE MITCHELL.

Witnesses:

FRANK B. DEHN. ALBERT R. RAMSEY.