Distilling of Flavor Additives

Simple and fractional distillation of organic compounds is a fundamental purification technique integral to organic chemists. Generally, distillation is introduced in an introductory organic chemistry lab sequence. However, despite the importance and prevalence of this technique in both research and teaching labs, there are limited examples of experiments whose focus is the distillation technique in the pedagogical literature. This distillation experiment seeks to address this need by providing a flexible and affordable distillation experiment that is coupled to an analytical technique to determine either quantitative or qualitative purity. The experiment consists of various aldehyde and esters that can be paired together and separated by distillation based upon difficulty of the separation, and cost; then analyzed with an available analytical technique (GC or IR spectroscopy) to determine purity. The compounds chosen for this study are all commercially used as flavor additives in candy. The utilization of common flavor molecules aids in connecting students to the everyday relevance of organic chemistry not often addressed in the curriculum.