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TSDCSTRIAL A S D ESGI-VEEHSG CHEMISTRY
the very complexity of the mechanism. Gobfeed machines with six heads require nine separate pieces of mold equipment for each head and additional parts for replacement of those worn in service. Just as many mold parts must be made for a n ounce bottle as for a 5-gallon carboy, and the design of the small bottle may require more labor in mold manufacture than that of an extremely large one. The trend of commercial packaging is, however, distinctly toward smaller containers. One feature of this trend is the demand for small bottles for jams, preserves, perfumes, and toilet articles dispensed in stores of the 5-10-25-cent claks. From a broad economic standpoint the trend ton-ard smaller packages costs the coiisumer more, since he must pay a higher per cent of his purchase money for the container when it is small and fancy than when it is large and plain. This trend, coupled with the desire for diversified styles of bottles, also helps to stock the mold storage rooms of the bottle manufacturer with tons of equipment used perhaps for only one run, the cost of which must ultimately be passed on t o the consumer, ~1.110buys his tomato catsup or his laxative pills in a newer and more striking container than he used to. While automatic equipment has revolutionized the bottle industry, and has carried that industry far on the road toivard completely mechanical operation, there is still a balance between hand labor and machinery in mold manufacture and
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in two operations in the plant. The first of these operations is the removal of finished bottles from the blowing machines t o the conveyors leading to the annealing lehrs, and the second is the removal of the annealed bottles from the cool ends of the lehrs in the storage and packing rooms. I n the first case, only bottles that are standard and are manufactured almost continuously are transferred from the finishing mold to the conveyor by means of take-out tongs; some sturdy shapes of small bottles are allowed t o fall from the mold onto the conveyor; and the remaining bottles, comprising special shapes and large sizes, are removed manually, because the operation can be carried out more cheaply in this way than by providing the multiplicity of transfer equipment which would be necessary to handle all ware mechanically. I n the second case, in the storage and packing room another factor enters into consideration, that of the visual inspection of the ware which is possible with hand packing. Until photoelectric devices become human enough to inspect bottles, the packing of bottles from the cool ends of the annealing lehrs will probably continue t o be done by hand. Acknowledgment
The writer is indebted to the officials of the Illinois Glass Company, and particularly to C. 11. Marsh, vice president, and t o J. W.Romig, plant engineer, for information and assistance in the preparation of this article.
Some Aspects of Cracking' A. E. Dunstan and R. Pitkethly ANGLO-PERSIAN OIL COMPANY, L O S n O N ,
I
K THE short span of tiventy years gasoline has become
a world-wide necessity. Many mho are still actively engaged in the petroleum industry can remember when the disposal of this fraction was a problem. Most of it was burned under steam boilers or stills, but today such a waste of valuable materi,d is unthinkable. Not only has the supply of gasoline obtainable directly from crude been completely absorbed, but the demand for motor fuel much in excess of that quantity has resulted in a n enormous production of synthetic and natural gasoline. The latter has been obtained from natural gas by absorption or compression methods, but the former, by far the largest contribution towards requirements, has bflen produced by cracking. Modern Cracking Processes and Their Limitations
Liquid-phase or pressure distillation processes, employing comparatively moderate pressures, have been responsible for the eiiormous production of cracked gasoline in recent years and their development has given rise to the modern cracking plant. It is remarkable that the few processes which have becomc commercially successful haye all developed on similar lines-namely, the provision of a tubular heating section and a large vessel wherein the reaction is completed and coke deposited. All rely on heat treatment alone for the decomposition of the larger oil molecules. The modern cracking processes can process almost any crude or residual oil for the production of motor spirit. It would appear, therefore, that motor fuel requirements can be satisfied for a n indefinite time simply by increasing cracking equipment. But there are limitations, as the requirements of lubricating Presented at a meeting of the Philadelphia Section of the American Chemical Society, Kovember 15, 1928
ENGLAND
oils, wax, pitch, kerosene, and heavy distillates must be provided. IYotwithstaiiding the success of modern liquid-phase processes, the ideal cracking process has not yet been invented. By heat treatment alone hydrocarbons of high molecular weight are decompoPed into compounds of lower molecular n-eight and lower boiling range, but it is practically and theoretically impossible t o do this without also producing coke or compounds of high carbon and low hydrogen content. All commercially successful processes are hindered in their application more or less by this effect. Patents innumerable have been filed which claim to eliminate carbon formation, but to date none of them have developed into profit-earning propositions. By combining hydrogen with the oil while under cracking conditions the deficiency in this element may be made up, but commercially satisfactory means for achieving this combination have yet to be invented. Bergius and the I. G. have attempted to satisfy the conditions, but after many years' work the world's markets are unperturbed and no flood of synthetic gasoline has been produced t o compete with the natural material. The amount of coke produced in liquid-phase cracking may be only a small percentage of the raw oil processed, but last year over a million tons of this material mere produced in the United States alone. Besides actual coke a large quantity of fuel residue is also produced, but the loss in oil represented by the coke alone can be calculated in millions of dollars annually. KO doubt the cracking process of today has been of immense economic value. It has assisted in the rapid development of motor transport and has been the most effective step taken towards the conservation of
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petroleum resources. Technologists generally may be satisfied with present ksults, but still the coke problem demands urgent attention. Research is busy on the problem and a promising step in the right direction is in the application of high velocity to the oil stream without overmuch decreasing the time factor. Method for Minimizing Coke Problem
An example of this ingenious method is specified in a recent invention ( 1 )* which relates to the cracking of heavy petroleum with the object of minimizing the production of carbon by maintaining a relatively high degree of turbulence in the oil stream and a relatively low velocity of flow. The high degree of turbulence is maintained independent of the rate of throughput and is imposed on the oil stream during treatment by imparting surges that rapidly alternate in opposite directions. The treatment is carried out in a continuous coil of the usual construction-i. e., straight lengths of tubing with rqturn bends. The oil is supplied to the lower end of the coil by a feed pump which determines the rate of flow and the throughput of the plant. The upper end of the cracking coil is connected to a cooler, which may be simply a continuation of the cracking tube provided with means for cooling the treated oil. The upper and lower ends of the cracking coil are connected, respectively, t o the opposite ends of the cylinder of a reciprocating pump, without valves, which imparts the alternating surge t o the column of oil under treatment a t a rate sufficient to produce the high turbulence required, irrespective of the rate a t which the oil is passed through the plant by the feed pump.
\ Figure 1-Diagram of Experimental Plant for Cracking by Application of High Velocity t o Oil Stream
The process is preferably carried out a t a high pressure in the liquid phase and no enlarged chambers or reaction vessels are necessary for the collection of coke, as the conditions of cracking are such that the temperature of the metal container and the temperature of the oil approach each other owing to the high turbulence produced. Without the use of the surge the difference of temperature between the tube and the contained oil would be so great that this ('skin'' temperature would produce coke in large quantity, which would bring the process to an end. After passing through the cracking coil, which may be heated in sections under control, the cracked product may be flashed into a dephlegmator wherein heavy residue, reflux oil, and motor spirit may be separated from the gas. The essential part of the invention, however, is the method by which a controllable velocity and turbulence of independent origin may be maintained in an oil stream. The highly turbulent state of the oil promoted by the surge, under conditions in which the oil is uniformly heated and under con-
* Italic numbers in parenthesis refer to literature cited a t end of article.
Vol. 21, No, 7
ditions of rapid heat transfer, does not favor the production of carbon or coke as a consequence of excessive heat on any part of the plant, as is common experience in known cracking apparatus. A plurality of surges may be imposed on a number of zones according to the heat input, so that a different velocity or turbulence factor may be applied in sections of the same appliance. It is possible by means of this apparatus to avoid many of the difficulties usually encountered in the cracking of heavy petroleum. Tubes of large diameter may be usefully employed with a reduction t o the minimum of the heating surface for a given volume of oil treated, and a large margin for carbon deposit is provided without the use of reaction chambers. I t has the added convenience that a very high pressure may be used without undue risk. The process has been carried out experimentally in a plant of a 100 gallons daily capacity diagrammatically illustrated in Figure 1. This plant consists of seven 1-inch tubes 6 feet long connected in series by return bends to form a continuous coil of solid drawn steel. The outlet end of the coil is connected to water-jacketed tubes of the same size and material to form a cooler in two sections, also to one end of the cylinder of a surge pump having variable stroke and variable speed, while the inlet end of the coil is connected to the other end of the surge pump cylinder and to the feed pump. Each of the tubes forming the coil is heated electrically and independently controlled by rheostats, so that heat can be applied under control to any section of the plant. -4s it starts through the cracking coil, the oil is heated rapidly to a temperature below that of active decompositionsay 380" C.-and in its further course is gradually and uniformly raised to 450" C., or a temperature a t which the oil actively decomposes. The application of heat may slowly continue, but in such a way that the skin temperature remains a t a minimum under the conditions of turbulence produced by the surge pump. Thereafter the oil temperature is gradually reduced as decomposition proceeds and vapor pressure rises, in order to obtain the maximum yield of light products without substantial vaporization. The treated oil is rapidly cooled while still under pressure, or it may be directly flashed into a dephlegmator. Thus the time taken for the oil to pass through the apparatus is only a few minutes. I n the experimental plant the conditions may be varied indefinitely, but to illustrate the method of working a Persian gas oil was treated to yield 23 t o 25 per cent of motor spirit boiling below 200" C. A Persian 65 per cent residue yielded 40 per cent by weight on the raw oil, of spirit boiling below 200" C. and a fuel oil free from carbon. The feed pump forced the oil into the plant a t a rate of about 4 gallons per hour, being thus to foot per second, while the surge pump worked a t 120 revolutions per minute giving the column of oil a velocity of 12 feet per second alternately in opposite directions. After passing through the coil, the cracked oil was flashed by an automatic relief valve into an evaporator a t the base of a column, yielding spirit overhead, a recycle oil fraction, and a fuel-oil residue which was free from coke and had a viscosity of 700 seconds Redwood a t 100" F. Throughout the operation a pressure of a t least 600 pounds per square inch was used. Comparison of Liquid- and Vapor-Phase Cracking
Recently the production of cracked spirit has been further stimulated by the demand for antiknock gasoline as, broadly speaking, cracked gasoline has a higher antiknock value than straight-run gasoline. It is only from certain crude oils that cracked gasoline containing considerable amounts of antiknock constituents can be obtained by the use of liquidphase cracking processes. On the other hand, the product
July, 1929
I-VD CXTRIAL A N D ENGINEERIXVG CHEXISTRY
from vapor-phase or high-temperature cracking has invariably a rery high antiknock value, so high, in fact, that it may be used to blend with straight spirit to produce a commercial antiknock mixture. It mould appear, then, that the liquid-phase processes have their use in supplying quantity requirements in excess of the yield of gasoline from crude oil, while vapor-phase processes should be developed t o supply the quality material for blending to produce the type of fuel necessary for the best results in the modern high-compression, high-speed engine. The aim of quantity cracking should be t o produce the maximum of saturated spirit in such a manner that a minimum of gas is produced, for the hydrogen lost IS largely contained in the gases produced in cracking by present methods. I n the vapor-phase or high-temperature method, however, it is necessary to eliminate hydrogen in order to produce the substances which have antiknock properties. It seems reasonable to expect that the cracking plant of the future will comprise both liquid- and vapor-phase steps, the residue from the former passing directly into the latter. I t is a matter of interest that when fifteen years ago the economic advantages of liquid-phase cracking became apparent, and Burton’s pioneering work bore fruit, the development of vapor-phase cracking almost ceased. The st.arch for antiknock fuels, hornet er, has revived interest in the high-temperature type of process and a considerable amount of work is being done to determine its possibilities and the utilization of its by-products. There are three or four commercial installations in existence which may well form the nucleus of a new cracking industry. At present the tapor-phase process still labors under the disadl-antages of heavy gas production and, if the process is carried to finality, coke deposits, particularly if a crude oil residue is used a s cracking stock. Here again we have the simultaneous production of gas and coke, but it is possible to eliminate coke almost entirely if the heaviest part of the raw oil is rejected before active cracking begins. The high yield of gas, depending in amount on the temperature of cracking, may be used as fuel, but with the heavy residue also produced an e x c w of fuel results. High-temperature cracked gases may contain 50 per cent or more of unsaturated compounds the nature of which is not completely known, but it is certain that by burning them there will be a waste of most valuable raw material. To date some of the higher alcohols have been manufactured from the,gas, but before complete utilization is possible the properties, not only of the gas, but of the other products of vapor-phase cracking demand intensive research. Generally the same types of compounds are found in liquid and vapor-phase cracked products (8) but in different proportions. Liquid-phase cracking produces a low percentage of unsaturated gases while vapor-phase cracking gives a very high proportion-30 t o 7 5 per cent. Liquid-phase cracking produces little ethylene and only a trace of diolefins, but vapor-phase-cracked gases may contain 25 per cent of ethylene and over 2 per cent of diolefins. Egloff (10) has drawn attention to the possibility of polymerization of the diolefins into synthetic rubber, and this point was mentioned many years ago by Sschen. Birch ( 2 ) has found high-temperature vapor-phase gas to be a convenient source of butadiene. Chemical Aspects of Cracking
Burrell (7) summarizes practically all that is known about the effects of cracking and finishes with the statement that has been emphasized so often-that there is a woeful lack of knowledge of the chemical changes involved in the process, urging the need for more and more research. It would
64 5
be overoptimistic t o believe that a complete fundamental knowledge of petroleum will be attained in our own time. That is recognized as practically impossible and some research workers have given up the problem in despair, but a t the same time fundamental research in certain directions has already been of value in explaining the mechanism of different reactions and processes. There are certain groups of compounds contained in petroleum and in the products of cracking which should be examined to ascertain a knowledge of their behavior under various conditions. For instance, the greenish yellow color particularly noticeable in cracked gasoline and more or less common t o all distillates has been a costly matter to the refiner. It is not known exactly what causes the color, but decolorization is necessary to make gasoline and kerosene marketable. The numerical value of sulfur content in gasoline is also a source of controversy. But here opinion is hardening in the direction of no precise specification so long as free sulfur and obnoxious odor are absent. The question immediately arises as to what constitutes purity in a gasoline, for since the color and other standards were instituted the viewpoint has altered. Formerly unsaturated compounds were looked on with disfavor, but now the more unsaturated compounds a spirit contains the higher it is valued provided that it is stable. Since antiknock value has become important, other values have tended to depreciate, for it is known that the treatment necessary to produce water-white gasoline definitely reduces the antiknock values particularly when the refining agent is sulfuric acid. Sulfuric acid treatment is still the great stand-by, but it is more than probable t h a t within a fern years the methods used today for refining cracked gasoline will have become obsolete. Special methods of refining depending on the polymerization of unstable hydrocarbons will appear, and in this direction there is a wide field for applied research. Probably the lack of knowledge of the chemical nature of the products of cracking is due in part to concentration during the last few years on a study of the physical and engineering rather than the chemical aspects of cracking, and the work done in determining the general effects of temperature, time, and pressure has resulted in improved furnace design, better temperature conditions, and greacer control over heat transmission. Recently, however, there has been more work done on the chemical nature of cracked gasoline. particularly with reference to analysis which could be correlated with antiknock value or, in other words, the determination of the proportions of paraffin, olefin, naphthene, and aromatic compounds contained in the gasoline. (See work of Egloff and his colleagues, 14.) Hill, Henderson, and Ferris (12) indicate that considerable research has been done from time t o time on the isolation of pure compounds from gasoline. Various chemical and physical methods have been devised to determine the proportions of the various series of hydrocarbons present, although these are only approximately accurate (3, 11, 13, 1.5). The analysis of a cracked gasoline into its component compounds alone presents a problem that requires more investigation as no reliable method has yet been suggested. Sachenan and Tilitscheyew (16) state that the lighter decomposition products of cracking and the heavier polymerized products are formed by different constituents of the crude oil. They deduce from their experiments that the paraffin hydrocarbons do not yield condensation products, and that pressure has a great influence on the proportion of olefins produced (but compare Brooks, ;), increased pressure having the effect of reducing the amount of olefins; also there is a com-. plete absence of naphthenes in cracked gasoline produced from paraffin wax. The inference is that ring closing of the
IhrD U S T R I A L A N D ENGINEERING CHEMISTRY
646
olefins with conversion into naphthenes plays no part in the cracking reaction. No coke is formed from paraffin and the specific gravity of the residue remains unchanged irrespective of the time of cracking. Heavy oils with a high aromatic content, on the other hand, yield a high percentage of coke. These diverse remarks refer to liquid-phase cracking and indicate the necessity for further investigation. It is noticeable that if paraffin-base oils are cracked in the vapor phase a t a high temperature, the products are quite different. The product from the liquid-phase cracking of a paraffin-base oil has an antiknock value little greater than the straightrun gasoline from the crude, but the vapor-phase cracked product has a n antiknock value which is vastly superior; in fact, under the right -conditions it may be superior to benzene in antiknock properties. Obviously me have two different propositions in liquidphase and vapor-phase cracking. I n liquid-phase cracking some of the components produced in the vapor-phase process may be present, but only to a small degree. Comparison of the products from both p r o c e s s e s shows outstanding differences in specific gravity, color, and gum-forming tendency. The gum-forming propensity of; vapor-phase cracked spirit is one of its most characteristic properties. The nature of
n
Figure 2-Apparatus
for S t u d y i n g Effects of Cracking
gum is unknown. Where gum is formed by aging of the cracked gasoline, oxygen appears to be necessary for the formation of a t least part of the product and it is acidic in nature (4), but the gum-forming substances may be polymerized rapidly by the action of Florida earth or other catalysts, or even by heat treatment. Little, however, is known about either the original or the final product. The gumforming substances boil within the gasoline range of temperatures and a method of conversion of these substances into useful products would be of great value. Many investigations have been made which have added t o our knowledge of various products of cracking, but the progress being made through applied research lies principally with the refining of the cracked gasoline for the production of marketable products. The constituents of cracked oil beyond the gasoline range have been neglected, and the position of our knowledge remains much as it did four gears ago when, referring to the work of Brownlee ( B ) , the possibilities of research on this material were indicated (9). With a knowledge of the principal constituents of cracked oil the nature of the chemical changes involved in the process would be elucidated. It is doubtful if even the simplest product of cracking-i. e., the gas-has ever been completely analyzed. As for the liquid products, only some of the lightest components hare been isolated.
Vol. 21, No. 7
Apparatus for Studying Effects of Cracking
Some of the effects of cracking may actually be seen b y employing an apparatus constructed for the purpose. This apparatus (Figure 2) consists of a horizontal steel cylinder filled with mercury and fitted with a plunger. The plunger rests on two bearings, the outer being threaded to engage in the threaded section of the plunger stem, and by turning this stem the pressure may be adjusted to any degree mithin the limits of the apparatus. A gland prevents leakage where the plunger enters the cylinder. Through the walls of the cylinder are holes into which are fitted a n open mercury manometer and lowpressure and high-pressure gages. The manometer and lorn-pressure gage may be brought into use or cut out by needle valves. At the end farthest from the plunger a fourth hole iq fitted with a gland into which a specially made clear silica tube 85 em. long and of 4 mm. bore is fixed. The silica tube is closed a t the top and has a shoulder a t the open bottom end to hold it in position in the gland and is capable of working up to a pressure of 1000 pounds per square inch (70.5 kg. per sq. em.). The upper or closed end of the silica tube is enclosed in an oven of special design, being heavily insulated around four sides, while double glass windows with a n air space between form the front and back. The interior of the oven is electrically heated and a motordriven fan circulates the hot air within the oven in order to provide a uniform heating medium, which may be maintained a t the desired temperature * l o C. A heavy iron stand with balance weight for raising or lowering the oven is conveniently situated and a pyrometer connected to a thermocouple within the oven registers the temperature. In order to obtain uniform conditions within the silica tube a novel stirring arrangement, comprising a loosely fitting steel ring within the tube and a movable electromagnet outside the tube, is provided. By moving the electromzgnet up and down the steel ring follows and efficiently stirs the liquid within the tube. I n order to operate the apparatus the silica tube is filled with air-free dry mercury and inverted in an open vessel of the same mercury. The amount of oil t o be tested is inserted in the tube by means of a bent pipet and fills the tube to a length of about 5 em. A rubber band is then stretched across the mouth of the tube while still under the mercury and the whole lifted and inserted into the open gland of the apparatus, the plunger of which has been previously adjusted so that the mercury in the apparatus is practically overflowing. The rubber band is removed and the gland of the tube tightened. Thereafter the oven is lowered and heat applied. The behavior of the oil under any desired temperature and pressure conditions may be thus observed. Critical temperatures and vapor pressures may be determined easily, and cracking phenomena are visible at the conditions of the experiment. Fundamental Research of A. P. I.
The reason why so many of the problems of cracking remain unsolved is the fact that research workers are so few in a vast uncharted field. Nost of them are working on processes or on methods of treatment and they work more or less independently. Scraps of their knowledge become published but little has been done to correlate this work and practically nothing has been done in the may of a general program for a massed attack on definite lines. The fundamental research program of the Central Petroleum Committee of the National Research Council, under the direction of the American Petroleum Institute is the first serious attempt in this direction. This program covers the whole of the industry from the origin of petroleum t o the compo-
July, 1929
ISDCSTRIAL A S D ESGINEEEZING CHEXlSTRY
sition of the final prodiicts. It is an ambitilms project. The result of the first two years’ work has been published in part. The projerts in force for the third year contain a considerable numbw of iteins of great interest t o the cracking section of the industry. One of the difficulties in fundamental research o n petroleum and its products lie. 111 the differences betlveer- crude oils. The properties of a crude oil or of its products before and aftpr cracking are distinct from those relating to another oil; still oils of a similar type will yield similitr products. Beyond that each individual crude oil must be separately investigated. It is possible that when cracking conditions reach the upper temperature limit for the production of liquid products in reaqonable quantity, the products obtained from almoqt any raw oil rvill b~ similar, but under liquid phase or semi-liquid pliase conditions the products of cracking may vary enormously, arid this is due wholly to tne chemical composition of the raw mnterial. Effect of Cracking on Engine Test of Oil The effect of different conditions of cracking on the engine test of an oil is interesting. A shale retorted in the usual way produced gasoline. kerosene, gas oil, and wax distillate. The gasoline had an antiknock value of +0.1 equivalent to an
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addition of 6.6 per cent of benzene t,o the standard zero spirit. The gas oil cracked in the liquid phase produced a gasoline with nn antiknock test of -0.1 and the gas oil and wax distillate when passed through a vapor-phase cracking unit produced a gasoline which gave an engine test equal t o 60 per cent of berizene in a straight-run spirit, the same straightrun spirit being used as a zero standard in all cases. Literature Cited Beale, Coxon, a n d Dunstan, British P a t e n t 293,889 (July 16, 1928). Birch, IND.ENG.CHEM., 20, 4 i 4 (1928). ( 8 ) Brame and Hunter, J . Inst. Petroleum Tech., 13, 794 (1927). (4) Brooks, I N D . EX. CHEZI., 18, 1198 (1926). (5) Brooks, Non-Benzenoid Hydrocarbons, p . 157. ( 6 ) Brownlee, British Patent 141,753 (1971). . CHEX, 20, (7) Burrell, Fuel Science Practrce, 7, 416 (1928); I N D ENG. 602 (1928). (8) Dunstan, Cantor Lectures, R o y . SOL.A r t ? , 1928. (9) Dunstan and Pitkethly, J . Inst. Petvoleurn Teciz., 10, 728 (1924). (10)’ Egloff, World Power Conference, London, 1828. (11) Garner, J . I n s l . Pelroleurn Tech., 14, 695 (1928). (12) Hill, Henderson, and Ferris, IICD. EXG.CHEM.. 19, 128 (1927). (13) Moore a n d Hobson, J . Inst. Pelroleurn Tech., 11, 589 (1925). (14) Morrell and Egloff, Oil Cas J , 2 5 , 156 (1937). (15) Ormandy and Craven, J . Inst. Pelroleurn Tech, 11, 533 (1925); 13, 311, 8 4 4 (1927). (16) Sachenan and Tilitscheyew, Petvoleurn Z., 23, 521 (1927); J . Insl. Pelroleurn T e c h . , 14, 761 (1928).
(1) (2)
Triethanolamine Oleate for Oil Sprays’ George L. Hockenyos DEPARTMENT OF HORTICULTURE, USIVERSITYO F
ILLIXOI$
URBANA, ILL.
HE last fern years have seen a rapid development in the with comparatively large droplets in suspension has been use of oil emulsions for insect control. This may be debated for some time. D e Ong(2) concludes that the work of attributed to the effectiveness, cheapness, and con- Griffin(5) hae decided the question in favor of the quick-breakvenience.of oil emulsion sprays and t o the fact that certain ing type of emulsion. The recent introduction on the market of Triethanolamine scale insects such as the San Josi. scale seem t o have developed an immunity t o the lime-sulfur sprays so long considered the in commercial quantities and a t a comparatively low price led to its use as a base for cutting oils in the form of the oleate standard control measure. Deyelopment in this field has been along three line.: (1) soap. The facts that this soap is reputed to emulsify large boiled oil emulsions made by boiling cheap alkali soaps with quantities of oil and that it is said t o have good penetrating oil and water; (2) cold mived emulsions prepared by emulsi- or softening qualities when used as a base for shaving soap fying the oil in water by use of an inert material as calcium suggest its desirability as an emulsifying agent for spray caseinate, glue, or hydroxide of copper or iron; 1:3) miscible emulsions and as a base for miscible oil sprays. oils, which when stirred in water, become emulsions. The miscible oils have found special use in greenhouse in- Properties of Commercial Triethanolamine and Its Mixture with Oleic Acid sect control, where the amount used a t any one time is likely to be small. Britton(l)* classifies the miscible oils into four “Commercial Triethanolamine” is the trade name for a groups: (1) lubricating oils with sulfonated vesetable oils product containing approximately 70 to 75 per cent triethanoland alkali; (2) sulfonated mineral oils; (3) lubricating oils amine, 20 t o 25 per cent diethanolamine, and 0 to 5 per cent with soap dissolved in phenols; (4) lubricating oils with soap rnonoethanolamine. It boils a t approximately 277” C. and dissolved in alcohol. 150 mm. It is a nearly colorless liquid of faint, ammoniacal The grade of oil used in any oil sprays should vary with the odor, fully soluble in water, and strongly basic. Mixed with nature of the insect and plant and with the season. I n gen- oleic acid it forms a stiff jelly which is easily liquefied by gentle eral, light oils are more destructive t o both insect and plant, heating. but are effective for only a short time; heavier oils, on the The soap is soluble in mineral oils, but considerable water other hand, are effective for a longer time and the cumulative is produced by the reaction of the Triethanolamine and oleic effect on both plant and insect is greater. For winter spray- acid, and some is present in both reagents. This settles out ing of dormant plant s heavy lubricating oils h:tve become quickly from oil solutions upon standing, but may be removed standard practice, nhile for soft-bodied insects, such as by boiling in a n evaporating dish. When foaming ceases, aphids attacking tender summer foliage, oils as light as kero- heating should be stopped to prevent decomposition of the sene are used. For most summer spray probleins and for soap. This soap-oil solution is not clear, but is quite satisgreenhouse pests the Comparatively light lubricating oils of factory for preparing emulsions. the highly refined, saturated type seem the b w t answer. The question whether an emulsion should be quite stable Preparation of Emulsion with fine droplets in colloidal solution or “quick breaking’’ Small quantities of emulsion for experimental purposes 1 Received January 31, 1929 e Italic numbers In parenthesis refer t o literature c:ted a t end of article. were made by putting the soap-oil solution in a large test
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