Type Analysis of Micro Crystalline Wax (Petroleum Wax) by Using Field Desorption (FD) Ionization
Introduction
Petroleum waxes are a class of hydrocarbons that are solid at room temperature and are classified by the Japan Industrial Standards (JIS K2235) into 3 types: paraffin wax, micro crystalline wax, and petrolatum. A typical micro crystalline wax contains hydrocarbons having a carbon number of 30 to 60 and molecular weights between 500 and 800. In addition to paraffins, these waxes also include large quantities of isoparaffins and cycloparaffins.
Field desorption (FD) is an ionization technique that utilizes the tunneling effect of electrons in the presence of a high electric field. The sample is applied directly onto an FD emitter filament, and then an electric current is applied to the filament to produce a high electric field across the emitter surface (including the whisker tips) to desorb and ionize the samples. As a soft ionization technique that minimizes fragmentation and produces molecular ions, FD has been previously used for analyzing refractory compounds and high molecular weight polymers.
In this work we ionized a micro crystalline wax by using a JMS-T100GC AccuTOF-GC with FD ionization to do a sample type analysis that was based on the mass and intensity of the resulting ions.