Aug. 6, 1968 C. B. MCCARTY EAL 3,396,204 HYDROBROMINATION OF OLEFINS IN A THIN TURBULENT FILM Filed Feb. 4, 1965 2 Sheets-Sheet 29

OLE FIN RAW MATERAL

H4 HYDROGEN BROMIDE 34 INVENTORS Kenneth W. Theie Chorles B. McCorty By 92.--Stoute ATTORNEYS Aug. 6, 1968 C. B. MCCARTY ETAL 3,396,204 HYDROBROMINATION OF OLEFINS IN A THIN TURBULENT FILM Filed Feb. 4, 1965 2 Sheets-Sheet 2

COOLANT NLET

OLEFN NLET HYDROGEN BROMIDE NLET

Fig. 2

INVENTORS Kenneth W. The ille Chorles B. McCorty BY W. C.Cutba. 42 2 4 a ATTORNEYs

—

3,396,204 3 4. a supply of cooling liquid 19, and inlet line 36, and an can be used in conjunction with an inert carrying gas or exit line 21. The reaction mixture exits rapidly from the driving gas stream such as nitrogen and the like. In a end of the reaction tube 13, into a separator 26, contain preferred embodiment, however, the hydrogen bromide is ing a mist eliminator 27. The reaction product is re brought into contact with the olefin reactant with such covered via a recovery line 28, leading from separator velocity that it is capable of being the sole propelling force 26. Unreacted hydrogen bromide is also recovered and for forming and maintaining a film of the olefin reactant. recycled through line 29, to the initial hydrogen bromide Inert ingredients when present in the hydrogen bromide feed line 5. driving gas are not necessarily harmful, but in the interest The description of the invention above in terms of a of economy and simplicity of operation, it is preferable rising film reactor which is in communication with the to operate solely with hydrogen bromide gas. One con liquid alpha olefin and an inlet means for introducing a IO sideration here is that hydrogen bromide gas which has hydrogen bromide gas stream is not intended as a limita been prepared according to a well-known bromine burn tion on the proper scope of the present invention. Those ing process, also contains small amounts of hydrogen and skilled in the art will readily be able to envision modifica inert gases. Continuous use of this means as a source of tions to FIGURE 1, including concurrent and counter hydrogen bromide can result in the build-up of the hydro current falling films, horizontally propelled films, coil gen and inert gases within the system to the point where reactors, as well as others. It is intended that the proper they may interfere with the efficient operation. In that breadth to be attributed to the present invention should event, it may become necessary to either remove these cover any process which calls for contact between the materials from the system or else use the accumulated gaseous hydrogen bromide and a thin turbulent film of the 20 mixture of hydrogen bromide, hydrogen and inert gases alpha-olefin reactant. However, the rising film process, as as a separate hydrobrominating agent in an auxiliary or illustrated in more detail in the examples below, rep secondary hydrobrominating unit. It is possible, according resents the preferred embodiment of this invention, since to this invention to use one or more secondary hydro it affords very high quality reaction product in a rapid and brominating units in conjunction with the main reaction efficiently controlled process. Moreover, by the rising 25 system described herein. film process herein described it is possible to react hydro The velocity or rate of the hydrogen bromide gas neces gen bromide and alpha olefins at higher temperatures than sary to establish the turbulent film can be determined heretofore thought possible and still obtain excellent for any desired set of reaction conditions and procedures. results. The requirement varies for different apparatuses. Olefins which can be treated in accordance with the 30 It has been discovered that for the preferred rising present invention are normally liquid alpha-olefin hydro film reaction system described herein, the input rate of carbons containing from about 5 to about 30 carbon the hydrogen bromide raw material to the system should atoms, and preferably 10 to 20 carbon atoms. The olefins be in the range of from about 20 pounds per hour to can be obtained from any source and include products 'about 110 pounds per hour, and preferably between 25 of catalytic and thermal cracking of oils, and those ob to 85 pounds per hour. In addition to the initial hydrogen tained by dehydrogenating the corresponding paraffinic bromide feed inlet that introduces fresh hydrogen bromide hydrocarbon or by dehydrating alcohols. So-called ethyl to the system at the proportions specified above, there is ene build up alpha olefins can also be used. These com a Substantial amount of unreacted hydrogen bromide pounds are typically made by passing ethylene into a that is recycled within the system. This was pointed out trialkyl aluminum at about 200 F. to about 400 F. and 40 above in the discussion of FIGURE 1. The quantity which at atmospheric or higher pressure for a period of from is recycled is on the order of from about 5 to 40 cubic about several minutes to an hour or more. Alpha olefins feet per minute, and preferably from about 10 to about of various and predetermined chain lengths are thus ob 35 cubic feet per minute. This recycle stream of hydro tained but those containing from about 10 to about 20 gen bromide insures that the olefinic reaction mixture is carbon atoms are preferred for use in this invention. The 45 maintained in a turbulent annular film. It is sometimes raw material alpha olefins can be maintained at room desirable to circulate the recycled fraction to a com temperature and need no preheating or precooling steps pressor before passing it to the initial raw material feed before being brought into contact with the hydrogen line. bromide. Examples of suitable alpha olefins are decene, If desired, the recycling line may be omitted complete dodecene, tetradecene, hexadecene, octadecene, and eico 50 ly from the practice of the present invention. When this Sene. Usually these compounds are prepared as mixtures is done, however, the rate of the fresh supply of hydrogen by the processes mentioned above. Such mixtures can be bromide to the system must in any event be sufficient to used directly in this process. Pure olefins also find perfect establish and maintain the turbannular film flow. application according to the present invention. A horizontal or a slightly inclined reaction vessel may So far as the gaseous hydrogen bromide reactant is require an adjustment in the velocity of the hydrogen concerned, there are no special limitations such as source, bromide as compared for example to a vertical unit. A temperature, etc. The hydrogen bromide, for example, rising film process as described above and which repre can be prepared when and where needed, e.g. via a well Sents a preferred embodiment of the present process re known bromine burning process, and used directly. Any quires possibly the greatest velocity since it propels, car convenient source can be used. As with the olefin reactant, 60 ries and maintains the olefin up through the reaction zone no special precautions are necessary such as cooling or as an annular film. In a modification wherein a falling heating. It can be kept at room temperature and used in film of olefin is used instead of a rising film, the velocity that condition. requirement will be determined in part by whether the In the preferred embodiment of the present invention, gaseous hydrogen bromide is passed concurrently or the gaseous hydrogen bromide should be added to the 65 Countercurrently. Best reaction results are obtained when System at a 5 molar percent to 20 molar percent over the the olefin film is in a turbulent state and this fact can be stoichiometric amount, the excess being necessary be used as a guide in favoring any given velocity rate for the cause of the solubility of the hydrogen bromide in the gaSeous reactant. alkyl bromide reaction product. FIGURE 1 depicts the hydrogen bromide inlet tube As has been mentioned previously, the present process 70 35, as being disposed centrally within the vertical reaction does not require the presence of any ingredients other chamber 13. Variations on this apparatus structure can than hydrogen bromide, alpha olefins, and a free radical be employed without departing from the spirit of the initiator as described hereinafter. Materials including Sol present invention. Vents, driving or inert carrying gases, while not neces A Suitable rate of addition of the organic olefin re Sary, can be used. For example, the hydrogen bromide 75 actant can be fairly easily determined. It will be de 3,396,204 5 6 pendent to some extent, of course, on the velocity of the formation that is necessary to catalyze the free radical ad hydrogen bromide addition rate. So far as the rising film dition should be used. Accordingly, it has been found process is concerned, the rate of olefin addition can vary that about 0.005 mole percent to about 5.0 mole per between about 25 pounds per hour to about 200 pounds cent of ozone when added to the olefin gives consistently per hour. A preferred rate of addition found especially good results in the practice of the present invention. It suitable for rising film reactions described herein is from is preferred to use from about 0.01 mole percent to about about 50 to about 150 pounds per hour. 0.6 mole percent of ozone. It is to be appreciated that the The present process is not encumbered by any critical olefin converted to ozonide is essentially lost to the de requirements for conducting the novel process under sired alkyl monobromide reaction product emphasizing pressure. The reaction can be conducted under pressures that the lowest possible mole percentages of ozonide ranging anywhere from 0 to 50 pounds per square inch O should be formed as are sufficient to catalyze the hydro gauge and higher. Primarily as a matter of operating an gen bromide addition reaction. efficient continuous process, it is preferred to employ pres The foregoing discussion illustrates the formation of sures of from about 5 to about 25 pounds per square inch an ozonide initiator in situ in the reaction stream. An gauge. 5 excellent alternative method also is available. The ozonide Whereas the reaction temperature, as stated above, initiator can be prepared by introducing the requisite can range from about 20 F. to about 120 F., it is pre amount of ozone into an auxiliary stream of an alpha ferred to operate within a narrower range of about 25 olefin raw material to form the ozonide and thereafter F. to about 100°F. feeding the auxiliary stream containing the ozonide initia As mentioned, the process of the present invention re 20 tor into the bulk of olefin raw material to be hydrobromi quires mixing the reactants in the presence of a free radi nated. The primary consideration is that the ozonide initia cal initiator; that is, in the presence of a material which tor is essential to the free radical reaction. It is less im can be photochemically or thermochemically decomposed portant whether the ozonide is formed in situ in the entire to form free radicals. Illustrative examples of com amount of the alpha-olefin raw material or whether it is pounds which can be used in this manner are organic per 25 preformed separately in an auxiliary stream of olefin and oxides, although other compounds can be used which then fed to the hydrobromination reaction zone. It is pos are not organic peroxides. The organic peroxides form sible, moreover to store the ozonides or olefins containing a particularly convenient source of free radicals as they effective amounts of the ozonide initiator in metal con are activated by a wide range of temperatures, and their tainers for long periods without any apparent reduction employment allows a close control of the reaction. By 30 in free radical activity. way of example, there can be mentioned hydrogen per The necessary dimension or thickness of the turbulent oxide, acetyl peroxide, tertiary-butyl peroxide, ascaridole, reaction film possibly can be best defined in operational turpentine peroxide, benzoyl peroxide, p-chlorobenzoyl terms. A film which is too thick or not turbulent enough peroxide, methyl n-amyl ketone peroxide, methyl isobutyl may not allow for the intimate mixture of the reactants ketone peroxide, methyl ethyl ketone peroxide, acetone which is necessary to optimize the reaction. In any event, peroxide, ethyl peroxide, and the like. Ingredients of the it should be clear that one skilled in the art, enlightened type of oxygen, air, or ozone can also be used since they by the teachings of the present invention, will readily be tend to form peroxides when contacted with unsaturated able to adjust the flow of raw material reactants as well hydrocarbons. as the reaction conditions to obtain the best possible The free radical conditions necessary for the present 40 results. invention can also be obtained by employing a photo As has previously been pointed out, the actual dimen chemical process of effecting the hydrohalogenation reac sion of the rising film will primarily be a function of the tion under the deliberate influence of ultra-violet radia rates and velocities with which the reactants are fed tion, and more particularly under the influence of light into the system. For the rates given herein, it has been rays having a wave-length of below about 2900 to 3000 45 determined that for best results the film thickness should angstrom units. This, of course, entails the use of addi be within the range of from about .001 inch to about .02 tional equipment, and for this reason such an embodiment inch. Optimum results are obtained with reaction films is less preferred. Excellent results can be obtained with ranging from about .005 inch to .01 inch. such a process, however, and may be found desirable There is an implicit teaching in the prior art that hydro under Some circumstances. 50 bromination reactions must be run at low temperatures The use of ozone represents a preferred embodiment for best results, even as low as -70 F. to -100° F. With of the present invention. Ozone for reaction with the ole regard to the primary to secondary ratio, the belief exists fin reactant to form the ozonide free radical initiator can that an increase in reaction temperatures, say above 50° be obtained or formed in any convenient manner. For F., favors the formation predominantly of the less desir example, the ozone formed by passing oxygen through able secondary bromide isomer. As a result, there has an ozone generator is satisfactory for use in the present never previously been a continuous, efficient, rapid, com process. mercially feasible hydrobromination process because of The essential ozonide free radical initiator can be the expense of running the reaction under rigidly con formed by passing ozone into the liquid alpha-olefin raw trolled low temperatures. It has now surprisingly been dis material being prepared for hydrogen bromide addition. 60 covered that this previously widely held belief is not The temperature of the liquid olefin during the addition necessarily correct and that by running the reaction ac of the ozone can range from about 10 F. to about 160 cording to the present process, it is possible to reduce or F. without noticeable effect on the subsequent reaction eliminate the expensive refrigeration units. Moreover, it with hydrogen bromide. It has been found that the reac has been discovered that this can be done at no substan tion to form the ozonide proceeds rapidly and smoothly. 65 tial sacrifice to the quality of the reaction product relative Normally all of the gaseous ozone passed into the liquid to previously used processes. Thus, this invention is much alpha olefin promptly reacts with it. This finding is more flexible and efficient than prior art processes since demonstrable in that overhead gases from ozonized oxy the reaction can be controlled by using a coolant having gen passed through an olefin do not give an oxidation a temperature ranging as high as 80° F. to 90° F., e.g. test when bubbled through a potassium iodide solution. 70 ambient room temperature. Experimental evidence pre Although the hydrobromination reaction will proceed sented below substantiates this finding. In terms of FIG when amounts of ozone on the order of, for example, 6 URE 1 the coolant 19, can be connected to any conven mole percent and higher are used, the net result is only ient Water source, e.g., tap water, or cooling tower water. to consume greater amounts of the starting alpha-olefin As has been mentioned above, the reaction of the hy raw material. Therefore, the least amount of ozonide 75 drogen bromide with the olefin occurs almost immediately 3,396,204 7 8 upon contact of the two reactants under the influence of from the reaction zone hits a mesh type mist eliminator a free radical reaction system. Completeness levels in ex- 27, causing the product to be collected in chamber 26, cess of 99% are consistently obtained within a reaction and collected via recovery line 28. The unreacted hy time of about two seconds under controlled reaction con- drogen bromide exits through line 29, and into vessel 30, ditions. Under less vigorous conditions and modified ap- 5 where the gas is directed by a baffle 31, to line 32, back paratus, the process can be adjusted to last several min- to initial feed line 15. If by chance any of the reaction utes, e.g., 8 minutes. Under optimum conditions, however, product also passes through the mist eliminator 27, and it is preferred to conduct the addition reaction for a period line 29, the vessel 30, is further designed to include a of from about two seconds to about 4 minutes. catch basin at its base where the product is trapped. When A particularly commercial adaptable method of con- 10 an excessive amount is collected, an alarm 37, is actuated ducting the present process is illustrated in FIGURE 2. and the system is automatically shutdown. It is a horizontal sectional view of an apparatus modified A review of Table I quickly evidences the excellent Somewhat from that illustrated in FIGURE 1. Whereas results obtained by the present invention. Conversion per FIGURE 1 shows a single vertical reaction chamber 13, centages in excess of 99.5% were obtained in every ex FIGURE 2 is a drawing of an enlarged unit comprising 5 ample run. In each example the reaction was completed five rising film vertical reaction tubes 13. It is this type in a very short time, i.e., a few seconds. The flexibility of enlarged unit consisting of a plurality of reaction zones and economic advantages of the present invention can which was used in the examples described hereinafter. The be appreciated from the excellent primary bromide to identifying numerals in FIGURE 2 are identical with secondary bromide ratios in the reaction products. Even those for corresponding elements in FIGURE 1. In FIG - 20 in the runs where the coolant temperature ranged as high URE 2, the olefin enters through inlet tube 38, into the as 60° F. to 80° F. the ratio of primary to secondary raw material chamber from where the olefin passes into bromides were excellent. the base of five vertical reaction tubes 13. The hydrogen Although ozonide free radical initiators have been used bromide gas reactant enters through inlet tube 15, to a in the following examples, it is to be clearly understood circular manifold 40, which connects with and directs the 25 and emphasized that the free radical reaction can be gas through five branch feed lines 41, to vertical inlet conducted in an equally satisfactory manner if other free tubes 35. As previously described the hydrogen bromide radical initiators are used in place of the ozonide. For gas passing upwards through tube 35, establishes and main- example, the ozonide can be replaced with the afore tains the alpha olefin as a rising film 18, evenly through mentioned organic peroxide initiators including hydrogen each of the vertical reaction tubes 13. 30 peroxide, acetyl peroxide, tertiary butyl peroxide, ascari The cooling chamber 20, surrounds the plurality of dole, oxygen or air, and the like, as well as the deliberate five reaction tubes. The reaction product is recovered influence of ultra-violet radiation as described previously. TABLE I Free Percent Radical Product Primary Avg. Initiator Coolant Olefin Hydrogen Distribution Bromide Compositiou of Raw Molec- Concen- Temper- Rate, Bromide Pressure, Conversion, Primary (100% Material Alpha Olefin ular tration, ature, b.fhr. Rate, P.S.1.3. Percent Bromidel Alpha Weight Mole o F. b.fhr. Secondary Olefin Percent Bromide Basis) Ozonide (1) C1-C18------c 178 0.3 30 50 33 12 99.5 34/1 97.0 (2) Ci-C18--- -- c. 178 0.2 30 100 56 2 99.5 3211 96.9 (3) C1-C18. a 78 0.2 30 00 56 7 99.6 30|1 96.8 (4) C12-C18- 0 78 0.3 30 100 57 2 99.6 301. 96.8 (5) C12-C18- --- c. 178 0.25 40 100 55 1 99.6 2911 96.6 (6) C1-C18. --- d. 78 0.04 60 100 56 10 99.7 2611 96.3 (7) C12-C18- -- c 178 0.25 65 100 54 1. 99,7 251 96.2 (8) C12-C18------d. 178 0.2 70 130 73 1. 99.7 2511 96.2 (9) C1-C18------c 178 0.3 80 100 54 7 99.8 2311 95.8 (10) C16-C20------b 246 0.2 80 100 41 11 99.7 22/1 95.7 (11) C1-C18--- - c. 78 0.3 80 50 30 7 99.8 2211 95.7 (12) C1-C18--- -- c. 178 0.3 80 50 31 2 99.8 2211 95.7 (23) C12-C18------o 78 0.2 80 100 54 12 99.7 2211 95.7 graphy.a Conversion b With as determined high molecular by moles weight alkyl average bromide olefins, permole particularly olefin calculated those above from C1, a standardit is not possible Iodine Value to obtain determination such high quality andyapor product phase in chromatog a conven tional type reactor without employing a solvent, since the alkyl bromides solidify at approximately 70 F. Fractional distribution.9f alpha Olgin W material: C16, 42.5%; C1s, 29.3%; C20, 25.0%; C22, C.2%. c Fractional distribution of alpha olefin raw material: C10, 0.3%; C12, 65.2%; C14, 24.8%; C16, 9.5%; C18, 0.2%. d Fractional distribution of alpha olefin raw material; C10, 0.2%; C12, 65.6%; C14, 24.3%; C16, 9.8%; C18, 0.1%. from the tops of each of the five reaction tubes and the A straightforward comparison between reaction prod unreacted hydrogen bromide is collected and recycled to ucts prepared according to (1) the present film reaction inlet tube 5. 55 process, (2) a two stage continuous backmix process, and Many runs were made to demonstrate the effects of (3) a semi-batch laboratory scale process impressively process variables on product distribution and conversion reveals the unexpected favorable aspects of the present percentages within the broad terms of the present inven- invention. tion. Several variables were considered: olefin rate, 50 to The figures given in Table II for the rising film process 130 lbs./hr.; hydrogen bromide rate, 30 to 73 lbs./hr.; free 60 are averages obtained from 16 determinations. The tem radical initiator concentration, .04 to 0.3 mole percent peratures given of 30 F. and 80 F. are of the coolant olefin ozonide; pressure, 7 to 12 p.s.i.g.; coolant tempera- surrounding the vertical tubular reaction chamber. The ture, 30 to 80° F. Of the several process parameters, the reaction temperatures are thereby maintained substan coolant temperature was found to have the most significant tially in the same range as the coolant temperature. Meas effect on the product distribution and the conversion per- 65 urements indicate that the reaction temperature is in the centages. same range as the coolant temperatures. The two stage In the following examples the process steps described continuous backmix processes comprised two recycle sys previously and apparatus presented in FIGURE 2 were tems wherein a fraction of a reaction mixture is recycled employed. The internal diameter of the vertical reaction back through the reaction vessel. The temperatures of zones or tubes 13, was 0.5 inch and they were 12 70 the coolant used in a heat exchanger through which the feet long. The hydrogen bromide recycle line 29, was recycled fractions are passed were 20 F., 40° F., and modified to include a safety feature which while not 50° F. These lower temperatures required the use of an essential to the successful practice of the invention was extensive and expensive refrigeration apparatus to sup considered to be a desirable safety precaution in a con- ply the brine coolant solution necessary to control the tinuous operation. The reaction mixture passing through 75 reaction. The results reported in Table II for the Batch 3,396,204 O Laboratory Scale Processes were obtained at reaction tem stream being sufficient to establish an annular flow of peratures of 30 F. and 90° F. In these latter runs, the a thin turbulent film of said reaction mixture within ozonated alpha-olefin mixture was placed in a reaction an unpacked tubular reactor which is in communica vessel and gaseous hydrogen bromide was bubbled tion with said liquid alpha olefin and an inlet means through. Any unreacted hydrogen bromide passed for introducing said hydrogen bromide gas stream, through the reaction mixture and was carried off by a said tubular reactor constituting a reaction zone ex ventilating hood. The batch runs were simulations of tending beyond the inlet means for adding the hydro much of the prior art reactions between olefin hydrocar gen bromide gas, said flow of annular film being bon and hydrogen bromide. maintained in said reaction zone as a film having a From the results presented below in Table II, it is evi O thickness in the range of from about .001 inch to dent that the present process represents a clean advance about .02 inch; in the art of hydrobrominating alpha olefins especially reacting said alpha olefin and said hydrogen bromide in those containing from about 10 to about 20 carbon atoms. said annular film within said reaction zone in the presence of a free radical initiator for from about 2 15 seconds to about 8 minutes at a temperature in the TABLE I range of from about 20 F. to about 120° F. to form a primary aliphatic bromide reaction product; and Product Distribution recovering said reaction product, Reaction Process Primary Percent of Bromide? 2. A process according to claim 1 in which the liquid Conversion Secondary 20 alpha olefin contains from about 10 to about 20 carbon Bromide atoms. (1) Formation of Rising Film as per Preced 3. A process according to claim 1 in which the tem ing Examples 30F. Coolant Temperature. 99.6 31/1 (2) Formation of Rising Film 80 F. Coolant perature of the reaction between alpha olefin and hydro Temperature------99.8 22/1 bromide is in the range of from about 25 F. to about (3) Two Stage Continuous Backmix Process: 00 F. 20 F. Coolant Temperature.------99.6 2011 25 40°F. Coolant Temperature------99.7 1611 4. A process for reacting hydrogen bromide and a liq 50 F. Coolant Temperature------99.7 1111 (4) Batch Laboratory Scale Process 30 F--- 99.6 22/1 uid alpha olefin containing from about 5 to about 30 (5) Batch Laboratory Scale Process 90°F. -- 99.6 8.4/1 carbon atoms in the presence of an ozonide free radical initiator to form primary aliphatic bromides which com 30 prises the steps of: reacting a liquid alpha olefin with ozone to form an A big advantage apparent from Table II is that there organic reaction mixture containing unreacted alpha is now made possible a simple, continuous, efficient proc olefin and a small amount of a corresponding ozonide ess for converting aliphatic olefins preferably long chain free radical initiator; olefins to primary alkyl bromides which can be practiced 35 providing a substantially vertical unpacked tubular re without the necessity of a large capital outlay for re actor above and in communication with said organic frigeration apparatus. Moreover, this has been made pos reaction mixture and an inlet means for hydrogen sible according to the present invention without sacri bromide gas; ficing the quality of the reaction product. Note should contacting said organic reaction mixture with an up be taken in Table II, for instance, that the rising film 40 wardly directed driving stream of hydrogen bromide reactions carried out with an 80 F. coolant temperature gas to form a reaction mixture of hydrogen bromide, have a slightly higher conversion rate than other proc said liquid alpha olefin and said ozonide, the velocity esses run at lower temperatures. More significant and Sur of said hydrogen bromide gas stream being sufficient prising, however, is the right hand column in Table II. to establish an annular flow of a thin turbulent film This shows the unexpected result that the primary to 45 of said reaction mixture within said substantially ver secondary ratio of a reaction product prepared accord tical tubular reactor, said tubular reactor constitut ing to the present invention (80° F. run) is comparable ing a reaction zone, the flow of said film of said to the primary to secondary ratios in similar reactions reaction mixture being maintained within said ver conducted at much colder temperatures. This was totally tical reaction zone as a rising annular film having a unexpected. The fact that such a process is possible has 50 thickness in the range of from about .001 to about not, prior to this invention, been known. The economic .02 inch; savings coupled with a high quality product is a very sub reacting said alpha olefin and said hydrogen bromide stantial accomplishment. By way of marked contrast, Ta in said rising annular film within said vertical re ble II also shows that the Batch Laboratory Scale runs action zone in the presence of said ozonide free radi conducted at 90° F. resulted in a very inferior product as 55 cal initiator for from about 2 seconds to about 8 regards the primary bromide to secondary bromide ratio. minutes at a temperature in the range of from about The art recognized preference for primary aliphatic bro 20 F. to about 120° F. to form a primary aliphatic bromide reaction product; and mides over secondary aliphatic bromides is well known. recovering said reaction product. The foregoing description of the invention has been 5. A process according to claim 4 in which the hydro presented describing certain operable and preferred em 60 gen bromide is added in an amount which is 5 molar bodiments. It is not intended that the invention should percent to 20 molar percent over the stoichiometric be so limited since variations and modifications thereof amount. will be obvious to those skilled in the art, all of which are 6. A process according to claim 4 in which the liquid within the spirit and scope of this invention. alpha olefin is reacted with from about .005 mole percent What is claimed is: 65 to about 5.0 mole percent of ozone; the flow of said film 1. A process for reacting hydrogen bromide and a liq of said reaction mixture is maintained within said vertical uid alpha olefin containing from about 5 to about 30 car reaction zone as a rising annular film having a thickness in bon atoms in the presence of a free radical initiator to the range of from about .005 inch to .01 inch, and the re form primary aliphatic bromides which comprises the action time in said reaction zone is from about 2 seconds steps of: 70 to about 4 minutes. contacting said liquid alpha olefin with a driving stream 7. A process according to claim 6 in which the liquid of hydrogen bromide gas to form a reaction mixture alpha olefin is reacted with from about .01 mole percent comprising said liquid alpha olefin and hydrogen to about 0.6 mole percent of ozone. bromide, the velocity of said hydrogen bromide gas 75 (References on following page) 3,396,204 2 FOREIGN PATENTS References Cited 892,329 3/1962 Great Britain. UNITED STATES PATENTS 927,114 5/1963 Great Britain. 2,058,466 10/1936 Kharasch ------260-663 2,385,200 9/1945 Friedel ------2285 xR 5 LEON ZITVER, Primary Examiner. T. G. DILLAHUNTY, Assistant Examiner.