Sulfuric Acid → Hexadecane

Participants

Reaction Steps

Montmorillonite K10 Dehydration/Oligomerization. In using the clay montmorillonite K10 as the acid catalyst for dehydration of THL it was discovered that azeotropic distillation facilitates removal of the water and is required for rapid and complete reaction. Other solid acid catalysts work for this reaction as well as water soluble acid catalysts such as concentrated sulfuric acid. The combination of acid catalyst and water removal leads to a very effective dehydration of the monoterpene THL. At a fairly large scale of 1 L, it was discovered that only 5 g of clay is required to afford complete conversion of THL to a mixture of 3,7-dimethyloctene isomers in a matter just a couple of hours. The benzene can be fully recovered and used indefinitely in the dehydration chemistry. Other azeotropic distillation aids such at toluene can be used in the process. Hydrogenation of the octene-isomers leads to near quantitative conversion of THL to 2,6-dimethyloctane (DMO). Ignition quality testing (IQT) of DMO afforded a derived Cetane Index for the fuel of 45, which compares very well with that predicted by theory.

Provenance & Evidence