Archive for the ‘Petro’ Category

Two Detector Solution to Analyzing Sulfur

Dan Li, Katarina Oden, Chris English, and Jason Herrington Sulfur compounds are reactive, corrosive to pipes, and destructive to catalysts in petroleum refineries. Sulfur emission are strictly regulated globally. When released into the atmosphere sulfur dioxide converts to sulfuric acid resulting in adverse effects on human health and the environment. Sulfur detection is found useful […]

Benzo[b]fluoranthene as part of the EFSA PAH4

I’ve already had one reader of my last post, Is separation of benzo[b]fluoranthene and benzo[k]fluoranthene on 5% phenyl-type GC columns really that important for environmental analyses? ask why I had benzo[b]fluoranthene in red text on the chromatograms.  I had planned to include something about it being on the EFSA PAH4 list in that post, but […]

Book Review: Echoes of Life: What Fossil Molecules Reveal about Earth History.

The year 1936 marks the beginning of organic geochemistry. It started with Alfred Treibs’ discovery of porphyrins in petroleum; compounds that closely resemble chlorophylls in plant matter. Another 25 years would pass before scientists recognized that these compounds, known as biomarkers, could reveal insights into the evolution of plants and animals spanning a time frame […]

The International Network of Environmental Forensics 2014 Conference

The International Network of Environmental Forensics (INEF) 2014 Conference will be held at St John’s College in Cambridge, UK from August 4-6.  Environmental forensics involves the use of a broad array of scientific techniques to not only identify a pollutant in the environment, but also apportion its introduction source and timing, often in support of finding a […]

Shoot-and-Dilute GC – Used Motor Oil and PAHs – Rxi-5ms GC Column Performance

In a previous post, I introduced the Shoot-and-Dilute GC concept to keep GC systems up longer.   A split injection with a Restek Premium Precision® split inlet liner with wool pays huge dividends in good sample transfer of active and polar and involatile analytes while simultaneously reducing the impact of “dirt” on the expensive GC column. […]

Shoot-and-Dilute GC – A Way to Keep GC Systems Up Longer to Help Lower Cost of Analyses

Dilute-and-shoot LC-MS/MS is a selective and sensitive technique often used in determining pesticides in foods.  Because of competitive ionization effects seen with electrospray (ESI) and atmospheric pressure chemical ionization (APCI) methods, quantitative accuracy suffers for trace compounds of interest when matrix coelutions occur.  Dilution of extracts (or sometimes raw samples) is a good way of […]

Screening for GROs and DROs using GC/FID (EPA 8015C)

There are many different types of methods for hydrocarbon analysis.   There are EPA methods for air pollution testing and for spills which contaminate waters and soils.  There are ASTM methods for testing petroleum products.  There are also methods for testing hydrocarbons in food packaging and other products.  Out of all of these methods, the one […]

Hydrocarbon ranges of Polywax® reference standards

Customers occasionally ask about the hydrocarbon ranges of the Polywax® materials which we sell.  Although these ranges can vary, the approximate values for each material are found below. Polywax® 500:   C20-C72 Polywax® 655:   C20-C100 Polywax® 850:   C20-C110 Polywax® 1000: C20-C120   Personally, I have never prepared solutions using these materials, so I used Google to […]

What makes your column a good High Temperature GC column?

In the last few years, the request for HT-columns (High temperature GC columns) has increased and a lot of promises have been made from different vendors. In fact, the possibility of running a GC column near or above 400°C would increase the possibilities of the GC technique quite significantly. In the petroleum industry, for example, […]

[20] What do Chromatograms tell us? Spikes on the eluting Peak and on the Base line

Chromatograms are like fingerprints.  If you can “read” chromatograms well, you often can find a plausible cause. In this series, we will show a series of GC-chromatograms that are obtained from users and discuss some potential causes for the phenomena. Then we can move into some solutions for improvement.       Sometimes chromatogram is […]