Week 2 - new tools in the lab

In my second week, I finally made it past most of the training and got to being productive. For the first time in my life, I had a true 40-hour work week and spent it in a brand new chemistry lab. This is also my first experience in a true lab other than the labs at Juniata, so it was certainly a new look. That being said, I'm already getting to work both with instrumentation that is foreign to me, and with some I'm familiar with, but using it for a different purpose. Being in an industrial setting, the processes are a lot different than the more experimental ones I'm used to at school. Here, I'm testing for much more specific information, and almost always know what I'm supposed to find. In the research lab at Juniata, you never really know what you're going to get or what to look for.

Here is a breakdown of a few of the new analytical machines/methods I am learning how to work with. For pre-clarification, it is worth noting for the lesson's sake that oils, waxes, and petrolatums are all products of crude oil that start as a mixture of impure, unsaturated hydrocarbons of varying structure and carbon number that are refined to become saturated, pure hydrocarbons, and these analyses are performed at various points in that process.

XRF (X-Ray Fluorescence)

A very important part of oil refinery and purification is the removal of sulfur atoms from the hydrocarbons (particularly when producing food-grade products). Although sulfur's presence can often be detected by its odor, the XRF provides us with an exact concentration of the unwanted element. We load our sample into the XRF on small, plastic "cups," and the machine fires an X-ray beam at the sample, exciting the outer electrons of the sulfur atoms and reading the fluorescence that occurs as a result, with which it can calculate a concentration of sulfur. The XRF uses radioactive materials to produce the X-rays, so it has multiple safety features in place to prevent any harm and is encased in a thick layer of lead.

Two regular GC's (left) and two HTGC's (right), all equipped with autoloaders on top

High-Temp GC (HTGC)

While I'm familiar with gas chromatography already, the GC machines in this lab are a bit different than I'm used to. First of all, these GC's do not a mass spectroscopy (MS) attached, so it works differently than the GC/MS we have at Juniata. Instead of shooting the separated materials into the MS, these GC's use a flame ionization detector (FID) at the end to measure the carbon numbers of the components of the oil, wax, or petrolatum. The HTGC performs at higher temperatures than the standard GC (very self-explanatory name), and is therefore capable of vaporizing heavier oils, waxes, and petrolatums, since they have higher carbon numbers and therefore longer chains and higher boiling points, as opposed to the lighter oils that we throw into the standard GC with lesser carbon numbers. The resulting

Preparation for 13 oil samples to go on the HTGC. The small vials have special rubber-centered caps that can be punctured by the autoloader

chromatograms are looked at to spot any unexpected components in the mixture and integrated to estimate boiling points by percentage. Since it is a mixture, some components with boil at different temperatures, so customers are often most interested in the 5% boiling point, a good baseline of maximum operating temperature at which most of the oil is still in liquid form. The HTGC uses cyclohexane as the mobile phase, and the standard GC uses hexanes.

The lab also has a special GC set up to analyze the purity of natural gas coming into the plant before it is used to produce hydrogen gas.

Stabinger Viscometer (SVM)

Viscosity testing using SVM (Stabinger Viscometer)

One of the most important qualities of an oil/lubricant is the viscosity (viscosity is a measure of resistance to flow... for example, water has a very low viscosity while honey would have a very high viscosity) and density. The viscometer takes care of that for us. By simply injecting oil samples into the tubes of the SVM and running a program, it takes measurements of viscosity at certain temperatures as well as the density, which we can report to customers and analyze to make sure it's about what we should expect from that product.

I will be using more new instruments in the following weeks as I continue to grow in skillset and experience. Next week, I will be performing FDA tests for the first time and continuing to learn about the different areas of the lab.