INDUSTRIAL A N D ENGINEERI.I% CHEMISTRY
October, 1928 NIJMBSR DATEOF ISSUE Brazil 14,837 March 20, 1925 14,838
March 20, 1925
14,877
April 11, 1925
Canada 224,422 274,050
October 3, 1922 September 20, 1927
274,590
October 11, 1927
France 588,710
November 18, 1924
588,711
November 18, 1924
588,712
Xovember 18, 1924
600,011
June 23, 1925
600,012
June 23, 1925
Great Britain 142,432 April 26, 1919 244,166 September 11, 1924
244,167
September 11, 1924
248,797
September 11, 1924
TIrm Processes for electrodepositing nickel metals and resulting product Method of coating metallic objects and resulting products Methods of electrodepositing nickel metals and resulting product Electrodeposition of metals Method of electrodepositing nickel metals and resulting products Process for electrodepositing nickel metal and resulting products Process for electrodepobiting nickel metals and resulting product Method of electrodepositing nickel metals and resulting product Method of coating metallic objects and resulting product Method of treating and couting ferrous metal bodies and the resulting products Method of treating and coating low-grade sheet steel stock and the resulting products Electrodeposited metals Processes for electrodepositing nickel metals and resulting products Methods of electrodepositing nickel metals and resulting products Methods of coating metallic objects and resulting products
NVMBER DATEOF I S S U B Italy 234,845 November 13, 1924
234,846
November 13, 1924
234,847
November 13, 1924
Japan 64,581
July 6, 1925
67,250
January 23, 1926
67,251
January 23, 1926
64,581
July 6, 1925
Norway 39,716
September 16, 1924
Switzerland 115,746 April 30, 1926
115,747
April 30, 1926
115,942
May 15, 1926
1099 TITLE Methods of electrodepositing nickel metals and resulting product Methods of coating metallic objects and resulting products Processes for electrodepositing nickel metals and resulting product Processes for electrodepositing nickel metals and resulting product Methods of coating metallic objects and resulting products Methods of electrodepositing nickel metals and resulting product Method of treating and coating ferrous metal bodies and the resulting products Sound records and method of producing same Processes for electrodepositing nickel metals and resulting product Methods of electrodepositing nickel metals and resulting product Methods of coating metallic objects and resulting products
I n addition to these issued patents, there are on file in the United States Patent Office a great many applications, part of which are under allowance and which further describe the process.
Fifteen Years of. the Burton Process’ Robert E. Wilson S T A N D A R D OIL C O M P A N Y ( I N D I A S A ) , W H I T I S G , IND.
IFTEEN years ago last January the first battery of Burton cracking stills went into operation a t Whiting, Ind. In view of this, and of Doctor Burton’s recent retirement, it is an appropriate &me to analyze briefly the direct and indirect effects which his contribution has had on the oil industry.
F
Operation Prior to 1910
Prior to 1910 practically all of the operations of the petroleum industry were batch, with low capacity, high labor and fuel cost, and little or no fractionating equipment, which necessitated repeated rerunning of the distillates to make satisfactory finished products. There were three general methods of running crude oil: first, skimming, in which the gasoline and kerosene were distilled off with steam and fire, leaving a fuel-oil bottom; second, running for steam-refined stock, in which the distillation with steam and fire was carried on far enough to distil out the gas oil and lighter lubricants, leaving a bottom which was refined with acid and fuller’s earth to give heavy lubricants or cylinder stocks; and third, running down to coke in the ordinary coking stills without using any steam. In the last-named operation the heavy ends of crude oil were destroyed by destructive disf illation a t atmospheric pressure, and gave (from midcontinent crude) around 10 per cent more kerosene and 2 to 3 per cent more gasoline than was present in the original crude. This cracking operation also gave 4 to 5 per cent of coke, and necessarily destroyed most of the heavier lubricating fractions. At the end of the operations the still bottoms were red hot, and 1 Paper presented before the Midwest Regional Meeting of the Amcrican Chemical Society, Minneapolis, Minn., June 8, 1928.
sagged rather badly from the mere weight of the coke, which was generally from 8 to 16 inches thick. Early Attempts to Increase Gasoline Yield
Around 1908-10 far-seeing refiners began to realize that gasoline was no longer a mere by-product of the industry, but that the demand for motor fuel would soon outstrip the normal supply, even if some of the light ends of kerosene were added to the gasoline. An intensive search was therefore begun for some satisfactory commercial method of making a substantial increase in the yield of gasoline obtainable from a barrel of crude oil. Those who investigated the literature found two possible types of process described therein. The first was the batch distillation under pressure of stocks such as the heavy ends of petroleum, shale oil, brown coal-tar oil, etc., in small, thick-walled retorts. When these cracking operations were carried out in direct-fired vessels so as to make any considerable yield of light distillate, the coke formation on the heating surfaces was excessive, and they soon became red hot, as was almost invariably reported. While such small, heavy retorts could be operated with fair safety under such conditions it was obviously foolish to contemplate any such type of operation in vessels 8 or 10 feet in diameter, which would be necessary in order to compete on a cost basis with the production of straight-run gasoline. As pointed out above, commercial coking stills sagged from the mere weight of the coke when they got red hot, and any pressure more than a few ounces had to be carefully avoided. It must be remembered that not only must the wall thickness of the vessels be increased in direct proportion to their diameter in order to give comparable strength a t a given temperature, but the increased depth of
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I N D U S T R I A L AND EiWGINEERI NG CHEMISTRY
oil which deposits coke and the increased amount of heat which must be put in per square foot of surface both tend to aggravate the hot bottom condition of the larger stills. An 8-foot diameter still with walls a foot thick would therefore be far more hazardous than an 8-inch diameter retort with walls an inch thick. Such processes, which were really designed for kerosene manufacture and generally made as much coke as gasoline, were therefore rightly considered as utterly impractical for commercial gasoline manufacture. The second general type of Small-scale cracking method described in the literature was to pass oil vapors through very hot tubes or over very hot checker-brick surfaces, but these methods gave excessive gas losses and a yellow, malodorous, highly unsaturated distillate, not deemed a t all suitable for commercial gasoline. I n the commercial gas-making art the yield of liquid distillate was only 15 to 20 per cent and this was highly aromatic, tarry, and could not be refined to resemble ordinary gasoline.
Development of Burton Process
Vol. 20, No. 10
long-time tests a t temperatures in the cracking range ;.h Y ows that the factor of safety in these stills was not so large as was originally believed, hundreds of them Fere operated in many different refineries, and it was over six years before there was any serious accident or rupture of any still, and that one was due to excessive localized corrosion. While the first battery of twelve Burton stills only went into operation in January, 1913, it is significant that before July 1st of that year 240 such stills had been authorized by the Standard Oil Company of Indiana, all of which were in operation within twelve months. The total number operated by this company reached 500 in 1917 and 880 by 1922. The earliest stills charged 8250 gallons, and took about 48 hours for a complete cycle of operating, including cleaning out between runs. The later stills were built something like a water-tube boiler, had a much larger capacity, and were fed with fresh stock during most of the operation. Almost a t once there was a demand from other oil companies for the full operating details and a license under the various patents and patent applications involved. After consideration and some- differences of opinion, the Indiana company decided to grant such licenses a t a royalty of 25 Per cent of the net profits. Within a very few years most of the larger Oil companies took out licenses, and many hundreds of stills were installed in different parts of the country. For
William M, Burton, Robert E. Humphreys, and their associates found, after two or three years of experimentation, that by distilling a particular distillate stock, gas oil, in large stills a t pressures above 60 pounds and at temperatures around 725" to 750" F. with a fractionating runback, and condensing under pressure, it was possible to make around 35 per cent of gasoline with only 0.1 to 0.2 per cent of coke, and about 2 per cent of gas; and further that if the residue in the still was then removed and redistilled to eliminate about 10 per cent of heavy asphaltic by-products of the cracking reaction, the resulting distillate could be recharged to a similar pressure still, either alone or with some fresh stock, and recracked to give a similar /NSULATlOH additional yield of gasoline. The same is true of the heavy ends carried out of the still with the gasoline. Thus by recycling to conipletion the yield of gasoline could be brought up to about 80 per cent of the original gas oil charged TTith only about 0.4 per cent coke and 6 per cent gas, a remarkable contrast to anything previously known. The asphaltic hy-products were found to make excellent road oils. The amazingly low yield of coke from this stock u n d e r these conditions is, of course, the factor which made it possible to do such extensive cracking in stills of commercial size without getting hot bottoms. Since the steel did not become much hotter than the body of oil, it was possible to use direct-fired 8-foot stills a t 75 to 95 pounds pressure with only a &/*-inch t h i c k w a l l . BUR7"7t/BE STlU However, no small amount of J p u r e l y physical courage was required to operate the first commercial unit, especially w h w six or seven years it was the only commercial process for nialcthe high pressure and temperature began t o force out the oil ing gasoline by cracking. The contribution of these stills to through the seams and the investigators had to demonstrate our imperative need for gasoline during the war can scarcely be personally to the workman that it was safe and feasible to calk overestimated; without them there would probably have had to be a complete prohibition of pleasure driving instead of them without shutting down. The length of the early stills was limited to 30 feet, because mere gasolineless Sundays. Although many improvements have been made in the-dethat was the longest sheet of such steel then available and bottom seams had to be avoided a t all costs. If any slight sign of the stills and accessory equipment, it is surprising how bulges formed as a result of incipient hot spots before the still long even the original batteries of stills survived the econocould be shut down, they were always straightened out before mic pressure of improved processes. While they resembled the next run in order to prevent any localized collection of the proverbial jack-knife in that the original stills and many coke, False-bottom plates were installed to catch much of other parts had been replaced on account of corrosion, these original batteries with very little change in construction or the coke, and make longer runs possible. Although our present knowledge of the strength of steel on operation remained in use a t Whiting until 1925, and many
I N D U S T R I A L A N D ENGINEERING CHEMISTRY
October, 1928
similar batteries are still being operated a t a profit-a remarkable performance in this age of rapid industrial evolution. For the past few years the efforts of the industry’s ablest technologists have been directed toward making cracking a more nearly continuous process, and they have achieved a remarkable degree of success, but most of today’s processes still employ Burton’s fundamental contributions o f distilling and condensing under pressure a relatively clean-cracking distillate stock, and recovering additional clean charging stock from the residue by redistillation outside of the cracking stills. Economic Importance Some notion of the economic importance of the Elurton stills may be obtained from the following statistics, which are necessarily only approximate with regard to the licensees, but are based on the best available information: BO-GALLON BARRULS 011 GASOLINE
Standard Oil Co.of Indiana Licensees, including ciistoms plants
MADEIN BURTONS T I L L S In 1915 In 1920 In 1925 2,576,700 5,825,100 10,062,100
S,386,4OO5 13,707,9004 _---905,300 _-__ ___-
Total 3,482,000 Total as per cent of total U. S. gasoline production 10 3 a Total as per cent of U. S. cracked gasoline production 100 These figures are approximate only.
14,211,5005 23,770,O0Oa 14 5.
11.05
96“
41a
In the fifteen years since the first commercial stills were installed a total of just about 200 million barrels of gasoline has been made in Burton stills. To have produced this amount of gasoline by the ordinary skimming methods would have required about 1billion extra (42-gallon) barrels of crude oil, and necessitated the uneconomic marketing of the enormous residue as fuel oil in direct competition with coal. As a means of oil conservation the Burton process has probably contributed more than any other factor. Indirect Effects
Not only the direct, but the indirect effects of Doctor Burton’s work have been important and far-reaching. In the
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first place, the cracking process gave the oil industry a measure of flexibility which it never before possessed. Instead of a refinery being a mere separation plant, which had the difficult problem of finding a market for various products in just about the proportion in which nature happened to supply them, it became a factory which could adjust its yield of different products to varying conditions of demand. For example, the ultimate yield of gas oil from midcontinent crude can now be varied from 45 per cent down to nothing, and the yield of gasoline from 25 t o 65 per cent or more, depending upon demand. Another by-product was the rapid improvement in methods and materials of construction, in valves and fittings, etc., but which redounded to the benefit of all refinery operations. Thus, the general use of bubble towers on refinery equipment is largely an outgrowth of their successful use on Burton pressure stills. However, by far the most important indirect result of Doctor Burton’s work was the change it made in the attitude of the practical men in the industry toward chemists and other technically trained men. There were chemists in a number of oil-company laboratories prior to that time, but they were limited almost entirely to purely laboratory work, and were generally not tolerated in the refinery yard. The outstanding success of Doctor Burton’s work, and the tremendous change it introduced into refinery operations, gave the technologists their opportunity, which they have not been slow to seize. As a result, technically trained men are today in almost universal control of refinery processes, and a veritable revolution has been wrought in both design and operation of our refineries. hlany of these men are being promoted to positions of executive responsibility in the various refineries and companies. Doctor Burton’s own rapid promotion to the presidency of his company and his success in that position have been both a stimulus to other technologists and a great aid in bringing the industry to recognize the importance and value of the chemist’s work. From the standpoint of either its direct production of new values, the royalty income which it produced, or its indirect effects on a great industry, the work of Doctor Burton and his associates stands preeminent in the industrial history of the country.
Thymolphthalein as Indicator for Titrimetric Estimation of Carbon Dioxide’ C. J. Schollenberger OHIO .%GRICUL’TJRAL
EXPERIMENT STATION,
NE of the most convenient procedures for estimation of
0
carbon dioxide, especially in cases where the gas is evolved from a dilute acid solution, saturated with moisture and possibly accompanied by some acid vapor, consists in absorption in standard barium hydroxide solution in a suitable apparatus, such as a bead tower2 or modified Meyer bulb tube.3~4 The excess barium hydroxide may be titrated and, if no acid vapor accompanied the gas, this titration is an accurate indication of the carbon dioxide. If acid vapor was absorbed with the carbon dioxide, an excess of standard acid may be added t o the solution after the first titration and the titration continued with a second indicator of the type of methyl orange, unaffected by carbon dioxide, or, preferably, the carbon dioxide may be boiled off and the cooled solution titrated with the indicator first used. This second titration is then a measure of the barium carbonate precipitated. Phenolphthalein is the indicator recommended for titration of excess barium hydroxide in previously published descriptions of the method, but is riot perfectly satisfactory4 for the reason that barium carbonate is sufficiently soluble to show it color with 1
2 8 4
Received April 16, 1928. Truog, J . IND. ENG.CHEM.,7, 1045 (1915). J . Asrocn. Oficial Agr. (Chem., 1, Part 11, 19 (1916). Schollenberger, J. IND. ENG.CHBM.,8,427 (1916).
WOOSTER,
OHIO
phenolphthalein, indicating a reaction above p H 8.3. By the substitution of thymolphthalein, which is now obtainable in high purity a t a reasonable price, as the indicator for the titration of excess barium hydroxide with standard hydrochloric acid, a much sharper and more satisfactory end point is secured, since this indicator shows no color below pH 10. Its brilliant blue color in more alkaline solutions is easily seen against the background of precipitated barium carbonate. It is used like phenolphthalein, about 0.5 ml. of an 0.5 per cent solution in neutral ethanol being a suitable quantity for 200-ml. solution to be titrated. Since the end point in the titration of excess barium hydroxide is a t an unusually high pH value, approximately 10, it is quite important that the blank titration of a pipetful of the barium hydroxide solution should be made with the same indicator, even though carbonate is absent and any indicator would show a sharp end point. If this blank titration should be made with phenolphthalein, end point pH 8.3, and the titration in presence of much precipitated carbonate with thymolphthalein, end point pH 10, the plus error involved would be about 0.1 ml. 0.1 N hydrochloric acid for each 100-ml. volume of the solution a t t h e end of the titration. On the other hand, the primary standardization of the acid, if not made by running a determination on a standard sample-e. g., of calcite-should be by titration against a carbonate-free hydroxide solution, using an indicator which changes nearer the neutral point.
