IHllHllillllll 118 876 1THSF AN EXPERIMENTAL “STUDY OFAiR ’ BLOWING OF ROAD OILS AND)? THEIR CORRELATION TO QUALITY Thesis for the Dogma of B. S, - W : . RAJ-Moore ' r‘ _ » 1937 ~ ~;:;:_ l A _. . ‘ WEEK) w} An EXperimental Study of Air Blowing of Road 3115 and their Correlation to Quality A Thesis Submitted to The Faculty of Michigan State C0114 ’0 .L‘ VP‘V \— of Agriculture and Applied Science Candidate for the Degree of Bachelor of Science June 1957 TH PSI: CONTENTS Introduction Calibration of Flowmeters Set up for Calibration of Flowmeters and Curves Air Blowing Procedure Aparatus for Oxidation Determination Oils used, Their Company and Refining Method General Table Type Tables Comparison Tables Viscosity-Temperature Graph Conclusion Summary Bibliography 10882-1 'U C. 7 00 (D "Introduction" In this investigation, tests are to be made on oils refined from crude petroleums which were formed by an exceedingly slow process deep in the earth ages ago. The petroleum thus formed is a very complex and variable mixture of hydrocarbons and in the process of refining, the various burning and lubricating oils are distilled off, leaving a residue which is a black viscous substance. The residue may consist of hydrocarbons of the paraffin series or may contain none of them, in which case, it is called asphaltic, or may be composed of both classes. Therefore petroleums are referred to as aSphaltic, semi- aSphaltic or paraffins, depending upon the characteristic of the basic compound. The residue from refining some kinds of petroleums is suitable for road construction without further treat— ment and is used thusly. However, in other cases the residue is either too hard or too soft and must be brought to the desired consistency by variation in refining pro- cess or by addition of asphalts or fluxes from other sources. (1) Sometimes a petroleum residue is subject to a pro- cess known as "Blowing." This process improves them for use in paving work. Briefly, it is a process whereby air is blown into the residue heated from 2OOOF to 40d'F and bringing the oil to a desired consistency. This process lasts from 5 to 20 hours. This results in a waxy asphalt of low ductility but reasonably stable. These aSphalts are known as "Blown Oils." (1) The hydrocarbons we are principally interested in are collectively known as bitumens. A bitumen is a mixture of hydrocarbon compounds either found as such in nature or artifically prepared by the distillation of bitumenous coals. The mixture of hydrocarbons in bitumens are so complex that it is most difficult to separate them into individual compounds; therefore we are limited to a Study of certain series or families of hydrocarbons contained in the bitumen; all members of such families have pro- perties of the mixture. It is these predominating pro— perties which determine the classification of the bitumen; that is, paraffins and asphalts. The physical difference between these is that paraffins are greasy and asphalts are sticky. Physically, bitumen accuring in nature are gases, liquids, solids or mixed, forming a heavy dark yellowish green liquid known as crude petroleum oil from which gase— ous hydrocarbons readily escape under ordinary conditions of pressure and temperature. When crude petroleum oil is distilled the following products result. Low boiling products 40°— 156’0 - gasoline collected by condensation 150°— EOO'O - kerosene collected by condensation High boiling point products Over 5002; heavy oils and greases and waxes depending on the characteristic of the crude petroleum. The oxidation of residua obtained from the distilla- tion of petroleum oils with air at elevated temperatures has been practiced in the United States for nearly 40 years (2) and there has been several research tests carried out on oxidation of oils some of which are; Oxidation of white oils (5), oxidation of drying oils (4), Indiana oxidation test for motor oils (5) and also oxygen absorption test on the constituents of asphalts. In this last test the amount of oxygen absorbed by asphaltenes, asphaltic resins, pet- roleum resins and light oils, which are the constituents of soft Mexican aSphalt is determined. It was found that the asphaltenes oxidized the most readily of any of the con— stituents under the conditions of the experiment (2). In another research problem, the low temperature oxidation of hydrocarbons was studied. Tests were made on spindle oils. The oils were subjected to air by blowing and the weight of water and carbon dioxide given off due to oxidation was notedlfi) The purpose of this experiment is to attempt to cor- relate, if possible, the oxidation of various oils with the quality of the oxidized oils as determined by various tests both before and after oxidation, and at the same time the oxidation is performed, to collect H O and CO formed as 2 2 3 as the result of oxidization and thereby determine the comparative amount that the oil has oxidized. Having the above data one may have an idea as to the oils comparative ability to be oxidized. Then by means of the bromine absorption test on the oxidized oils it can be decided if the two compared show any consistency as to the amount of oxidization. If so, the two may be used to an advantage in the future. It may be however, that due to other chemical actions in the bromine absorption test, they will not indicate the same. Knowing the qualities and properties of the oils before and after oxidization one will be able to cor- relate the oxidization of the oils to the qualities. It is certain that the change in quality can be determined but it is another thing to correlate the quality with the oxidization of the oils. Since the oils which are to be oxidized come from different locations are also prepared for distribution by different methods of refining, such as; cracking, blending, cutting back, steam refined, and straight run; and since it is known that the oils are composed largely of bituminous substances having very complex chemical structures it is quite plain that no two oils are alike. As pointed out before, certain chemical substances predominate in some oils, while in others it is absent or present in smaller amounts. This may alter the effect of oxidization upon the various oils. Thus it would seem that all oils would not be affected the same when air is blown through them. There are various properties which complicate the correlation of oxidization to the quality of the oils and much must be done before there can be a definite correlation. This investigation is but a very minute part in the attempt to do such a thing but it is hOped that the data collected will in some way aid directly or indirectly to enable a very def- inite correlation of the oxidization of oils and their quality. As a first step, the oils will be taken as a whole and the effect of oxidization noticed. No attempt will be made to correlate the quality and the amount of oxi- dization on the oils. Having performed this it may be possible to correlate the oils as to types. Then finally, if possible, the amount of oxidization will be correlated to the quality and grouped according to types; or so to speak attempt to answer such questions as which oils are effected most by oxidization. Do the oils group them- selves according to the way they are refined? Procedure Calibration of Flowmeters In order to pass a definite amount of air through the oil it was necessary to have a flowmeter in the set up. The flowmeter consisted essentially of a capillary tube D having a bore of approximately a millimeter spanning the two ends of a U tube containing water. The pressure drop in the capillary tube was thereby indicated by the dif- ference of level in the liquid of the two arms of the U tubes. It was of course, necessary to calibrate the flow~ meters used since no two are exactly alike. This consis— ted in determining the relation between pressure drop and volume passing through the flowmeter in unit time. A constant pressure was maintained at G, which was accom- plished by adjusting the head of water in F by raising or lowering J depending on the amount of pressure desired. The higher J is raised the higher the pressure. The clamp at M enabled finer adjustment to desired pressure. Having adjusted to a desired pressure, water was then drawn off at H at such a rate that the levels of water on the manometer I, remained constantly level to each other, thereby causing air to pass through the flowmeter at a uniform rate. Thus, the total volume of water drawn off was equal to the total volume of air passing. Therefore, the volume of air in cubic centimeters per minute which passed through the flowmeter at a certain pressure differential as shown by the flowmeter was known. The difference in the level of QNKWSRQVL‘ KQ \(fisksvkmxflxu tQK n\\~ numb. . MGR. ; m. m «Ghost I . it < - figugosl [l a. Low i/i‘ fit ‘fiDmmmml / O \ .Qsh‘ /5 I4 [3 lo a - CV07”). Vo/wne floss/fly IC' 0 9 ID ‘--~M —. ‘— L L 7v A H *1 l v o. «fi-‘o4 v k Ii- 4-6 L pt“ O A v 0.0+. ”—4—. ‘0 L. V goods-6 /I77/'/7. ’00 c my - c. Volume pass I‘ /4 li // /0 "> Q m u f {s water in the flowmeter was plotted as abscissa and the correSponding volume of water passing in cubic centi- meters per minute was plotted as an ordinate thus de- termining a point on the calibration curve. By raising or lowering J, the pressure was altered and thus several points on the calibration curve were determined. Having these points the curve was then drawn. Air Blowing of Oil Procedure In order to get an idea as to how much the oil was oxidized when air was passed through it, the set up shown in Fig. 2 was used. The air was first passed through a solution of sodium hydroxide (NA 00+ NaOH) the following chemical reaction resulting to tikeECO out of the air; CO-kNaOHeéNaHCO or in other words thegcarbon dioxide in th: air was remgved from it by the CO uniting with the . soda lime to form sodium bicarbonate. The concentrated sulphuric acid was used to remove any moisture that might be in the air. It was necessary to remove H O and CO from the air as these elements would render Eoid the ge- termination of CO and H 0 passed off from the oil due to oxidation of the ill as Ehe air is blown through it. From the sulphuric acid bottle the air passed through the flow- meter and then through the trap whose purpose as can obviously be seen was to prevent any water from the flow- meter from getting into the oil. From the trap the air passes into the blower and is blown through the oil. The oxygen of the air has ample Opportunity to oxidize the oil 8 >6R <>§\ .QvSQ .1ch 0L. Ob h W nioxtws tom . bflttk / Ed 23"— 20 .5 til _' ,l _ F UQRUSQQ‘S‘HRN {L (Q “\— khk N¥ovP.m00m_> I'lll'hl I l . If ’I I." I ll lull. I m . m 3m WuxOFmrh—‘UU >.P_m00m_> . , CENTISTOKES VISCOSITY I bl'll hl‘r‘l Vl‘h Vb" I IVI‘I \Uh 0') 0 03 (I) (O Conclusions Air Blowing increased the specific gravity of all the oils. The Specific gravity does not increase according to amount of distillation which indicates that air blow- ing does increase the Specific gravity. All oils became more viscous and since they do not increase according as the specific gravity increases or to amount of distillation, indications are that air blowing makes the oil more viscous. Generally, oils having high asphaltene percent are the most Viscous oils which indicates that air blow— ing effects the aSphaltenes probably more than any other constituent. Generally oils which showed the 1. showed the least change in viscosity and 01 CR st ch lso t Change in Specific gravity. Anamalous results were obtained in the bromine tests on H and I. On observing the percent of 820 which was high, it is logica.l to assume that the unsa tur- ated compounds formed were of a type that did not polymerize.as completely as the other oils. All the other oils were found to have a decreased bromine absorption which is indiCative of polymerization of unsaturated hydrocarbons. There seems to be a tendency where the percent by veig ht of as phaltenes are righ, for gIe ater formr tion of 820 while those having low asuoaltenes give off less 820. This shows those having less asphaltenes have hydrocarbons of a more saturated nature. The fact that I Chang ed from a heterogen tive to slightly positive, indic:te s t became overheated or m13siL1y some Chet may have caused it. It is likely I is unsaturated hydrocarbons. Air Blowing tends to ma} e the ning p int higher safets as indicate d by the graphs in coznrc tion 'ith vis- cosity deteIr ination at different t 28 10. 11.. 15. 14. 15. 16. 17. 18. Considering the oils which were steam and vacuum re- fined, there is indication that they tend to group their- selves according to the comparatively highly oxidized oils as shown by the bromine test. They also group their- selves into low viscosities. So generally the indications are that steam and vacuum refined oils have high oxidation but are not effected so much as the oils having lower oxidation. Considering the oils which are a blend of steamed re- fined oils, there seems to be no possible way to corre- late the oils to amounts oxidized to the quality. This is probably due to the fact that the oils are not composed of like blends. Considering the oils which are a blend of steam refined residue, it is found that the oil had medium oxidation but low increase in viscosity. Considering the oils which are blended cracked residues one notes N has a high increase in viscosity and also a high oxidation rating, indications are that this type of oil is easily oxidized and a high viscosity results. Considering the straight cracked oils, Oil A has a high increase in viscosity but a low oxidation. 0 has a fair increasing viscosity and a fair oxidation. Indications are they cannot be correlated according to type. Considering steam refined oils cut back with gas oils, in- dications are that they cannot be correlated to type. As for the method of determining the C02 and 320 it should be stated that the entering effects of volatile material and the effect of polymerization made it very difficult to to make any decisions as to eliminate correlation of the oxidation to the quality of the oil. The bromine test gave a more accurate indication as to the amount of oxi- dation. Viscosity----Tam er tare graphs were used to determine temperature at 253 C hoppers Viscometer being used. Noting the Viscosity--Temperature graphs it will be seen that the oils have nearly the same slope, indicating that all oils are affected about the same at different temper- atures. 29 19. The graph showing 011 A, and Oil B before and after air ,blowing indicates that the oils tend to have the same slope before and after air blowing. This shows that the oils were properly heated and held at the reguired temp- erature. 20. Generally air blowing did not change the oils from a nega— tive heterogentry to a positive heterogentry. SUMMARY It is found that oils subjected to air blowing at a temper- ature of 1800 C become heavier in gravity, harder, more viscous and higher in softening pcdnt. It is also apparent that the aSphaltenes play a big part in determining the characteristics and quality of the oils. As to the correlation of the amount of oxidation to the quality of the oil after being subjected to the air blowing, there seems to be little tendency for the oils to group their- selves according to types. This is probably due to the Wide variation in the properties and sources of the original crude petroleum. 30 (l) (5) (4) W (6) Bibliography Construction of Roads and Pavements by Agg. Oxygen Absorption Test on Asphalt Lonstituents-- B. R. Thurston and E. C. Knowles. Industrial and engineering Chemistry 28: Jan. '36. Studies in Drying Oils; Oxidation of Linseed 011-— R. S. Taylor and J. C. Smith. Industrial and Engin— eering Chemistry 28: Feb. '36. Oxidation of White Oils-~R. W. Darnte. Industrial and Engineering Chemistry 28: Jan. '36. Indiana Oxidation Test for Motor Oil by H. Rogers and B. H. Shoemaker. Industrial and Engineering Chem- istry; Nov. 15, '34. Law Temperature Oxidation of Hydro Carbonse-J. L. Lewis, Journal of the Chemical Society 72; Jan. '26. Origin of Petroleum, H. Ries, Scientific American 140: Jan. '29. What is Petroleum? Scientific American 141: Aug. '29. Oxidation--Heduction Reaction between Natural Hydro- carbons and Oil Filled Water. Science 79: Jan. 12, '34 Oxidation of Motor Oils and the Effect of Tar Pesidue on Friction Results. Oil and Gas Jan. '34 and Aug. 15, '35. Some Chemical Aspects of the Origin of Petroleum-- S. C. Lind, Scientific News 73. Jan. 9, '31. Chemical Compounds Present in Petroleum: Oil and Gas: Jan. '35. and Feb. 25, '37. Chemicals in Petroleum Refining, Chemical Industry 40: Feb. '37. 31 . .I . 11: lint '1I?.l III .In'. .1! $1: DnnM IKE ONLY .1“, .44- )>-r\ if}; > E. ‘:I.pl~18l.fl‘--fl ‘