US3341344A - Road binder and surface coating from coal - Google Patents

Description

COMPRESSIVE STRENGTH PSI Sept. 12, 1967 H. H. GINSBERG ETAL ROAD BINDER AND SURFACE COATING FROM COAL Filed March 2, 1965 IOOO- :2: 200- E g I50 O 0*. 0. 20 O oilo 0:20

DEFORMATION INCHES DEFORMATION INCHES F/G'J F761? E 250- 200- i 5 I50- 5 I00 8 50 DEFORMATION' INCHES INl/E/VTORS F HENRY H. GINSBERG 3 MART/IV 0. scams/mm RAYMOND W H/TESHUE A TTOR/VEYS United States Patent Ofiiice 3,341,344 ROAD BINDER AND SURFACE COATING FROM COAL Henry H. Ginsberg, Martin D. Schlesinger, and Raymond W. Hiteshue, Pittsburgh, Pa., assignors to the United States of America as represented by the Secretary of the Interior Filed Mar. 2, 1965, Ser. No. 436,699 4 Claims. (Cl. 106281) ABSTRACT OF THE DISCLOSURE A paving composition composed of an aggregate and an asphaltene binder derived from a coal hydrogenation process.

The invention herein described and claimed may be manufactured and used for or by the Government of the United States of America for governmental purposes without the payment of royalties thereon or therefor.

This invention relates to the use of coal-hydrogenation asphaltene as a binder for paving and construction materials.

FIGS. 1, 2 and 3 are graphs of compressive strength versus distortion of briquets prepared according to applicants invention (FIG. 1) and prior art briquets (FIGS. 2 and 3).

Various types of asphaltenes have been used as ingredients in binding compositions for roofing or paving and for lining pipes, conduits, etc., and in coating compositions. Such compositions have, however, generally failed to provide the compressive strength required for a high quality paving material.

It has now been found that the use of a particular asphaltene, that obtained from coal hydrogenation, as a binder results in a product having desirably high compressive strength, as well as resistance to solvent action of petroleum products such as jet fuels. These properties are of particular value when the products are used for construction of air port runways or where automotive vehicles stand for periods of time. In these areas jet fuel and gasoline drippings and spillage can attack petroleum asphalt binders and cause serious damage.

The paving and construction materials of the invention comprise an aggregate, such as limestone or slag, and asphaltene derived from coal hydrogenation. The asphaltene is prepared according to the following description.

Conversion of coal into liquid fuels by the hydrogenation process consists of adding hydrogen to the coal at elevated temperatures and pressures in the presence of a catalyst. A two-step operation is employed in the production of gasoline. In the first or liquefication stage, the coal and the oil in which the coal was suspended are converted to a product which includes a broad range of hydrocarbon and oxygenated compounds from low-boiling to undistillable oils. The heavy fractions are recycled with fresh coal. The lighter and middle oils boiling up to about 325 C. are used as feed for the second or vapor-phase step. In this second step the distillable oils are converted to gasoline or other specification fuels.

The asphaltene of the invention is recovered by solvent extraction with benzene and n-hexane from the nondistillable oils from the liquefication step of the process. The heavy oil is first treated with sufiicient benzene to remove all the soluble oil, leaving as a residue insoluble coal- ]ike material and ash. Most of the benzene is then recovered by distillation. The oil residue is then treated with nhexane and a heavy tarry-like precipitate, asphaltene, is formed. The n-hexane is removed by filtration and heating and the asphaltene is used with aggregate in the preparation of the products of the invention. An alternative method would be to produce a product consisting mostly of asphaltenes and unreacted coal by the hydrogenation of coal at short residence times. The asphaltenes plus unreacted coal would not be separated but would be mixed, as is, with limestone.

Properties of the asphaltene are given in Table 1, along with corresponding properties of petroleum asphalt, conventionally used as a tion compositions.

TABLE 1.-ANALYSES OF ASPHALT AND ASPHALTENE M Air blown Asphaltene petroleum from hydroasphalt from a genation of midcontinent Rock Springs, crude, wt. pct. Wyo. coal, wt.

' pct.

Moisture 0. 00 Trace Ash 0.02 0.85 Ultimate (mat):

H 10. 7 6. 3 87. 5 91. 6 0.6 1.7 S 0.8 0. 1 O (by difference) 0.4 0.3 Benzene ins0luble. 0. 13 2. 8 Asphaltene 20.0 69. 6 Difference asphaltene 1 15.1 34.8 Difference resins 1 4. 8 34. 8 Resins 59. 1 19. 3 Oils 20. 2 21. 2 Solubility in CC 9997 Solubility in OS 99.95 Softening point; (R and B) F 114.0 110.0 Distillables to:

300 C 0. 0(1 1.24 355 C 0.52 2. 66 Penetration at 77 F., mm. l0 72. (1 119.0

Difierence asphaltenes and Difierence resins are solvent separated iractions of asphaltene. Difference asphaltenes are soluble in benzene but insoluble in ethyl ether.

Although limestone is the preferred aggregate used in preparation of the products of the invention, other maters such as slag or gravel may be used. The particle size and amount of the aggregate are not critical and will vary considerably depending on the particular use of the product. Generally, the particle size will vary from about /s in. to No. 10 US. sieve size and the amount of aggregate will be about to percent by weight of the composition.

The aggregate, such as limetones, is dispersed in the asphaltene by heating to a suitable temperature and mixing the two ingredients. Application of heat, usually about C., is necessary to maintain the asphaltene at a viscosity suitable for mixing.

Although the two-component mixture of aggregate and asphaltene has been found to give very good results, other materials, such as the conventional binders petroleum asphalt or tar, may also be included in the composition. Mixtures of diiferent types of aggregates may, of course, also be employed.

The following example will serve to more particularly describe the invention.

Example I Briquets prepared from limestone and coal-hydrogenation asphaltene were compared with similar briquets prepared from limestone and petroleum asphalt (penetration grade 85-100) or high temperature coke-oven tar. Analysis of the asphaltene and asphalt are those given in Table l. Cylindrical briquets 4 inches in diameter and 4 inches in height were prepared, by moulding, from limestone aggregate and coal-hydrogenation asphaltene, petroleum asphalt or coke-oven tar as binder. The limestone aggregate had a particle size of 50% to Main. and 50% A in. to No. 10 sieve size and comprised 90 percent by weight of the composition. Binder and aggregate were heated sep- Patented Sept. 12, 1967- binder in paving or other construcarately to about 165 C. (about 110 C. when tar was used as binder). The heated materials were then combined and mixed for about 2 minutes so that the aggregate was all coated by the binder. The mixture was then poured into a mold and spaded to eliminate void spaces. Molding was done at 125 C. for asphaltene and asphalt and at 105 C. for tar, under a compressive stress of 3000' p.s.i. held for 2 minutes. The specimens were then removed from the mold, oven cured at 60 C. for 24 hours and then cooled to room temperature in a desiccator.

The briquets were tested according to ASTM method D1074-58T in which an axial stress is applied to the briquet which is unsupported laterally. The stress is applied so as to obtain a uniform rate of vertical deformation, until complete failure occurs. Results are shown in FIGURE 1 for coal-hydrogenation asphaltene, FIGURE 2 for petroleum asphalt and FIGURE 3 for coke-oven tar. Superiority of the coal-hydrogenation asphaltene is evident: the maximum compressive strength for the coalhydrogenation asphaltene product is about 1800 p.s.i. whereas that of the coke-oven tar products was 425 p.s.i. and that of the petroleum asphalt product only 250 p.s.i.

In addition, after the maximum strength of the coal-hydrogenation asphaltene briquet was reached, it did not crumble as did the briquets made with petroleum asphalt. Resistance of the coal-hydrogenation asphaltene briquets to solve action of hydrocarbons was shown by negligible weight loss when they were immersed in ]P4 jet fuel at room temperature for 24 hours; results are shown in Table 2.

TABLE 2 Loss in wt. of Briquets: of binder, percent Petroleum asphalt 8 Coke-oven tar 3 Coal hydrogenation asphaltene 1 Although the properties of the composition of the invention make it of particular value for construction of airport runways, it is also of value for a variety of other uses such as road building, construction of moisture barriers, preparation of water-resistant surface coatings, etc.

What is claimed is:

1. A paving and construction composition consisting of a mixture of an aggregate and a binder consisting of asphaltene derived from hydrogenation of coal.

2. Composition of claim 1 in which the aggregate is limestone.

3. Composition of claim 2 in limestone in the composition is by weight.

4. Composition of claim derived by (a) contacting nondistillable heavy oils from said coal hydrogenation process with benzene to extract oil from said heavy oils;

(b) separating said benzene from said extracted oil;

which the proportion of from to percent 1 wherein said aspahltene is (c) contacting said extracted oil with n-hexane to precipitate said asphaltene therefrom; and (d) separating out said asphaltene.

References Cited UNITED STATES PATENTS 2,366,657 1/1945 Sorem 106-273 XR 2,658,026 11/1953 MacLaren et al. 106-273 XR 2,673,814 3/1954 MacLaren 106-273 XR 2,913,389 11/1959 Heithaus 94-20 XR 3,074,807 1/1963 Dorius et al. 106-273 ALEXANDER H. BRODMERKEL, Primary Examiner. I. B. EVANS, Assistant Examiner.

Claims (1)

1. A PAVING AND CONSTRUCTION COMPOSITION CONSISTING OF A MIXTURE OF AN AGGREGATE AND A BINDER CONSISTING OF ASPHALTENE DERIVED FROM HYDROGENATION OF COAL.

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