(Contribution from the Research Department, Battelle Memorial Institute) 



RESEARCH ON HYDROCARBON OILS 



by Ray E. Heiks 



ABSTRACT^ 



In order to investigate thoroughly hydrocarbon oils as wood preservatives, 

 a wide variety of samples of creosote oils and petroleum oils were col- 

 lected. The creosote oils included distillates from coke oven, vertical 

 retort, and horizontal retort tars. The petroleum samples included fuel 

 oils, recycled gas oils, and other oils described as "highly aromatic," 



The initial experimental work involved studies of the infrared spectra 

 of all of the oils in efforts to determine whether the creosote oils dif- 

 fered fundamentally from the petroleum oils. The results of these studies 

 revealed that the creosote oils contained a greater predominance of aro- 

 matic carbon-hydrogen bonds than the petroleiam oils. The rcxtio of the 

 optical density of alj.phatic and/or naphthenic carbon-hydrogen bonds to 

 aromatic carbon-hydrogen bonds varied from 11 to '}>(:i for the petroleum 

 oils and between 0,5 to 6,0 for the creosote oils. Comparison of the 

 infrared spectra of all creosote oils indicates that they are quite simi- 

 lar and significantly different from the petroleum oils. Many absorp- 

 tion bands found in creosote oil are missing in the petroleum oils, \irhereas, 

 all of the bands found in petroleum are also found in creosote oil. 



In an effort to studj?- the oils more precisely, two samples of creosote 

 Yirere subjected to fractionation under vacuum, in a column 39 inches long 

 by 3/U inches in diameter, packed with 1/8 by 1/8- inch stainless steel 

 gauze. The column had an efficiency of 50 plates at atmospheric pressure, 

 A l500-ml, charge was cut into 1 percent volume fractions. The reflux 

 fraction was 20 to 1, A total of 8? cuts were taken from the coke oven 

 creosote and 70 cuts were taken from a vertical retort creosote. Fractional 

 distillation under vacuum was considered to be a good means of separating 

 creosote into fractions containing a small number of individual components. 

 It was found that very poor separations vfere obtained, probably because of 

 the large number of azotropes that are formed in the mixture. An illus- 

 tration of the poor separation obtained is shown by the fact that phenol 

 was found in fractions boiling over a U3-degree temperature range and 

 naphthalene in fractions boiling over a 53-degree temperature range, A 

 mixture of phenol and naphthalene was found in Fractions 2 through 6, 

 boiling between 183 and 211°C. It was concluded that distillation alone 

 did not appear to be adequate in separating creosote into its components. 



In comparing a vertical retort creosote -.dth a coke oven creosote, infra- 

 red spectra^'showed that phenolic OH compounds appeared in all fractions 

 boiling up to 380°C., and there vfas even a trace in the last fraction 

 boiling at 39$°C,, whereas in the case of the coke oven creosote, no 

 significant amount of phenolic OH compounds were found in any fractions 



R - 1 



