Document 4v40eNEMeZbKr4ooQ56woV1bR

t LEAD INDUSTRIES ASSOCIATION 60 EAST 4 2 n d STREET N E W YORK 17, N. Y. Yi/HY CONTINUE WITH TETRI ETHYL LEAD? By D. P. Barnard Research Coordinator, Research Department Standard Oil Company (Indiana) A Bedouin sheik on his death bed called in his three sons and instructed them on the division of his property. To the eldest, who \vould succeed to the father's title and responsibilities, he bequeathed one-half; to the next eldest, whose responsibilities were less, one-third; to the youngest, one-ninth. After their father's death, the three sons set about dividing the property in accordance with his instructions. All went amicably until they came to his herd of 17 camels. Disputes then arose which became bitter to the point of bloodshed. At this point the eldest demonstrated his mature judgment by suggesting that they consult a wise man who lived in the neighboring village. So the three brothers took the herd of 17 camels to the tent of the sage and laid before him their apparently insoluble problem. The wise man heard them and then said: "My sons, do not quarrel further. As you see, I an but a philosopher and, therefore, poor in wordly goods. I have but one camel. However, I pray that you take my camel - add it to your father's herd and then divide in accordance with his wishes." And so the sons took the wise man's camel and added it to their 17. Then the eldest took his half of the 18, which vas nine camels, and departed content; and the next eldest took his third, six camels, and also departed content. To the youngest, whose share was one-ninth, went two camels and he was satisfied. Whereupon the wise man, noting that his camel remained, took it back and again tethered it in its accustomed place behind his tent. The point is that a bit of objective soul searching may be in order. Lead tetra-ethyl was once quite necessary, but now that the early critical problems have been solved, could it, like the wise man's camel, be retired? Lead tetra-ethyl as an anti-knock compound was introduced commercially in 1923. At that time, the automobile was underpowered, and the roads were, by present standards at least, relatively unimproved. Steep hills were the rule rather than the exception. "Spark knock" as it was then called, vas a real obstacle to technical progress. So when Midgley and his co-workers showed that this knock could be suppressed by means of fuel chemistry with resulting freedom to raise compression ratios, increase power, and also improve fuel economy, lead tetra-ethyl in the form of ethyl fluid performed a basic service. As a matter of fact, over the years TEL has made two major contributions: First, by lessening the knocking tendency of a fuel, it has actually improved that product. Second, by inspiring the engine designer to get the most performance from the fuel, it has paved the way to advances in engine design which, in the aggregate, have contributed more to technical progress than is represented by the fuel improvement alone. By this is meant that if we were forced to revert to 55 octane number fuel, we would lose less than half of the performance gains of the last three decades. -*Fresented at the 29th Annual Meeting, Lead Industries Association, Chicago, 111., April 2k-25f 1957 W 0004818 Tetra-Ethyl Lead -2- D, P, Barnard In appraising the octane number problem - and therefore the use of TEL it is necessary to bear in mind that the driver's evaluation of car performance will be determined mainly by the excess horsepower available for increasing the car's speed. Back in the days when improvement in anti-knock value was so necessary to any improvement in car performance, the typical automobile was built with a far smaller engine relative to its size, weight, and power requirements than the present car. Thirty years ago a 3500 pound car might have as much as 60 horse power under its bonnet. Of this, some 20 horsepower might be required to maintain hO mph cruising speed on level road with, say, hO horsepower remaining. This "surplus" or "reserve" power for acceleration - including hill climbing - therefore amounted to only 1 horsepower per 100 lbs. of total car weight. Obviously, any increase in engine power showed up as a substantial increase in reserve power. This was demonstrated time and time again. A 60 horsepower car might be employing say, 55 horsepower to maintain speed up a (10$) grade, with only 5 horsepower left over for passing purposes. In such a case, a 5 horsepower (or less than 10$) increase in total engine power showed up as a 100$ improvement in net horsepower available for passing an obstructing vehicle. A 3500 pound car still requires about 20 horsepower to maintain a level road speed of, say, 1*0 miles per hour (or about UO horsepower at 60 mph) but with installed horsepowers of 200 or higher, a loss of even 50 horsepower in the reserve available for acceleration would be of less importance than was 5 horsepower in the early days. In fact, most of the cars produced in the last few years cannot use- ' fully employ all of the power provided, let alone the much larger power claimed. In all probability, any currently produced passenger car power plant could have its compression ratio reduced and other design modifications made to adapt it to fuels well below present octane number levels. If TEL were eliminated and octane numbers reduced by, say, ten units, the passenger automobile would have as much horsepower - including reserve for all acceleration needs - as was available only a very few years ago. Obviously, such an automobile would be as useful as the most exotically powered ones of the moment, although, perhaps not quite sc spectarulcr Improved engine efficiency has been cited as a prime advantage of increased anti-knock quality ever since TEL was introduced more than 30 years ago. In the earlier days we heard much about the outlook for smaller engines with smaller appetites.. Only a shade over a year ago Gibson (of Ethyl) presented a most inter esting and excellent paper before the American Chemical Society in which he said: "It has been estimated that the octane numbers from the use of TEL in gasoline give a saving in gasoline consumption of about 10$ as the result of increased engine and vehicle efficiency. This is a saving of about 130 million barrels or more than 5 billion gallons of gasoline in the past year, and is a consumer saving of more than #1.5 billion." While these higher octane numbers might have been used to improve car mileage, the practical fact is that they have not been so used. The potential bene fits have rather been taken in the form of bigger engines for increased performance, heavier cars, automatic transmissions, and the like - all of which make the car more attractive but reduce the miles travelled on a gallon. Even within the engine itself the better possible efficiency of high compression ratios has been largely offset by the poorer economy characteristics of multiple barrel carburetors and other compromises made in the interest of high "advertising horsepower". The fact is that the American motorist shows no real concern for fuel economy and, therefore, neither has the car manufacturer. The talk about improved economy from high com- TetranEthyl Lead *3 6 D, P, Barnard prossion engines using high cetane number fuels is rarely appreciated by the public because they are unable to grasp the vast difference between "Miles per Gallon" and "Ton-Miles per Gallon." Actually, the number of miles through which a gallon of gasoline moves a representative automobile has improved slightly since 1930. How ever, increased weight, higher driving speeds, and faster accelerations (with inevitable increased breaking) pretty well use up the technical improvements in fuel economy. Then, too, the public does not realize the amount of gasoline required to operate power windows, power seats, super generators, air conditioning, power steering, etc. That is why some writers claim that progress in economy is little more than academic discussions by engineers and promotional hocun by hucksters. This situation exists because automobile manufacturers must make the type of automobiles which the public likes and which sell competitively rather than those which the public should use for technical or economic reasons. Were the automotive industry to arbitrarily make only what was good for the public, octane numbers could be reduced, but since tetraethyl load w `uld still be the most economic way for the oil industry to provide the final octane numbers to any gasoline, it still cannot be reasoned that load tetraethyl-- having solved the initial technical problems, and having paved the way to revolutionary advances in engine design -- might new, like the wise man*s camel, be returned to "pasture" -- sc far as its technical need is concerned. . This speculation raises several questions: (l) If lead is no longer needed for technical reasons, why is it currently used? (2) If it is still attractive, is its use to endure? (3) If the use of lead as an anti-knock is to continue, is the level likely to change? (light we decrease the amount per gallon now that to can get along without it? Is there any reason to consider a possible increase in dosage? Or is the TEL content reasonably likely to remain at somewhere near present levels?) Whenever a member of a government organization delivers a paper, it is invariably prefa.ced with a reservation couched in somewhat the following terms: "The views herein expressed are solely those of the author and do not necessarily represent the policies or views of -----------------the Government of the United States". With this hedge, I take the liberty of giving you my reasons for guessing that the use of lead tetra-ethyl as an anti-knock will continue in line with the customs of recent years. First, lead tetra-ethyl is used, along with other knock rating improvement processes, bucause it contributes octane number which is necessary to the successful marketing cf gasoline, Automobile merchandising is based on style, and impulse buying just as much as is the product cf the eminent Christian Dior and his contemporaries. So far as I am aware, no engineer currently engaged in the development and manufacture of the American automobile would for one minute claim that the present car looks like anything that which he himself would have dreamed up. Since the passenger car selling business is based on a combination of exotic appearance and "advanced performance" - it becomes fairly obvious that any . economically tolerable device that contributes to either of these two style factors, whether it be fishtails, swept wings, or a bigger horsepower number, is more than just useful. It is necessary to the present "art" of automobile selling. Octane number is just as essential to the "art" of gasoline selling. To the lay public, horsepower means performance. If the advertised horse power is higher, the car is expected to perform better and, therefore, it is a more desirable car, 'Since the public is sc attracted by horsepower (even though they Tetra-Ethyl Lead -h - D. P. Barnard probably cculdn*t understand less about its significance) it is obvious that the fuel manufacturer has no choice - even if he wished otherwise - than to exploit fuel characteristics which abet the horsepower story. I have just hinted that advertised horsepower may not be a direct measure of car performance. The point here, as you fully appreciate, is that performance of a car is really determined by the relations between factors such as rolling resistance, windage, internal friction, etc. which make up the total resistance to motion to be overcome and the engine torque available for overcoming this resistance. All of which, when appropri ately analyzed and plotted, tells the engineer the number of pounds of thrust available to increase the speed or rate of climb of a car under any particular set of conditions, and all of which is as intelligible as Swahili to the car salesman and to the American motorist. "Horsepower" is strictly a sales term. It was devised by Janes Watt many years ago for just that purpose. Watt was attempting to s ell his steam pumping engines to the Welsh r al mine operators. The mines in those days wore usually pumped with horses. Watt found that he could not impress the mine operators .with such terms as lbs. of water lifted X No, cf ft. of the lift per lb. of steam, etc. To compete with the Newcomen and other engines as well as horses, he had to convince the mine owners that his engine would work at a rate which would replace some impressive number cf horses. The hoi'sepower term is the product of effort X speed (one hp = 33,000 ft. lb/min.). By definition, horsepower is zero when there is no motion even though the power plant - man, horse, cr engine - may be straining with every muscle. By the same token, no horsepower is actually being used by an auto mobile at the instant cf starting. The impressive "prestige" horsepowers of auto mobile sales promotion exist (after much discounting) only at maximum engine- speeds and can be realized, if at all, only at quite high road speeds or sometimes in low gear at maximum engine speeds. (Not at all with torque converter reduction.) Virtually any American automobile new built has a power plant - engine plus trans mission - which can slip the wheels even on dry pavement. This, in combination with the development of the modern highway with its virtual elimination of steep grades, implies that the car could do as well with less horsepower to feed. (Incidentally, the automobile engine will consume at least one gallon of fuel per hour for each 8 horsepower developed. Customer reaction, if he actually used the advertised high outputs, seems obvious.) However, "prestige" horsepower is with us and, so far as we can see, it is here to stay. There is no point to speculating about what would happen to the use of knock-improving methods if the basis of cur business were different. We do have an effective style merchandising procedure and we must continue to live with it. In all probability, if we thought it threugh, we would not wish it too different. Just as the cheapest moans cf increasing automobile engine power is useful and valuable to the automobile business, so is the cheapest means for improving the anti knock characteristics of its fuel useful to the gasoline business. Those observation: apply to such other quality improving processes as catalytic reforming, alkylation, etc, and also to other anti-knocks - should they become practical. TEL takes its place and must compete with these other methods. Sc, in answer to the first two questions, it is my feeling that the use cf lead is currently logical and that its use will continue, so far as we can see, because it makes an important and econo mically rational contribution to a necessary sales characteristic of our product, K'E' 0004S21 ; Tetra-Ethyl Lead - $- D. P. Barnard The other question as to possible changes in level cannot be answered quite so categorically Since the very start, industry has accepted what is practi cally a self-imposed upper limit of 3 cc's per gallon. Thus far, this limit has agreed well with the economics of lead utilization. As we add lead to any gasoline the returns for successive increments diminish as TEL content increases. We get nearly 1/2 of the anti-knock improvement we are ever going to get from the first cc. The second cc adds about 1/2 of the improvement achieved by the first one, while the third cc usually adds no more than 1/2 of the increase due to the second. The economics of this phenomena are fairly obvious As we approach the 3 cc level, we get less improvement per unit of TEL, Other octane improving processes, there fore, become progressively more attractive. With respect to a possible decrease in generally used lead levels, this, frankly, does not seem to be indicated. The point is that the foregoing ''law of diminishing returns'1 works both ways, and as we consider reducin' TEL level we are giving up progressively cheaper octane units. Even though the third cc may give us only about one more octane raunber (on the average) at present levels, it is still ccmpetetive with other means of obtaining these desired high octane numbers. Also, it provides useful flexibility in nsoufaehiring to any particular oo-ane number specification. These points could be belabored ad nauseum, but I doubt if we would cone to any other conclusion than that lead usage in terms of cc's per gaHLon will tend to stay at about the present level - so far as we can see at this time. Admit tedly, this level might be forced down or even out in case of some national emergency. Excepting for such a disaster (when motor gasoline octane numbers would be our least worry) it can be considered that the TEL industry has a rosy future. To summarise, therefore, since we must do the best we can to compete in the business we are actually in and likely to remain in, TEL is not slated, to be tethered with the wise man's camel. The use of tetra-ethyl lead as an anti-knock will continue along established lines for the forseeable future. In other words, we will use TEL as long as style selling dominates the automobile and gasoline industries.