[garrysy]

Hello,

Can any advice which one (below) is best suited EDXRF for Petroleum Oil Analysis.

1. NEX QC+ QuantEZ - https://www.rigakuedxrf.com/nex-qcplusez.php
2.  Panlytical Epsilon 1 - http://www.panalytical.com/Epsilon-1-range.htm


Thanks.

[marquis]

What elements are you looking for in petroleum oil analysis?

[garrysy]

We are looking at Phosphorus, Sulfur, Zinc, Chlorine & Calcium.

[marquis]

Well, let's talk about a few important points.  Then you will want to send each vendor samples and see how they work out.

First, some of the elements you mention are heavily attenuated by air.  There are two ways to handle this, vacuum and helium.  If your samples are volatile, helium is your only choice.  Make sure both instruments can handle the option you choose.

Then there are filters.  Filtering the xrays can dramatically increase the sensitivity of some of your elements.  See what filters the instruments come with and what sensitivity is claimed.

Finally, send out examples for the company to analyze.  And watch them do it, if possible.  Sometimes some weird analysis tricks get used when analyzing samples.

Finally, there's money.  You and your managers will have to work that one out.

I have used edxrf analyzers for all of the elements you mentioned.  Its a question of limits , analysis time, etc.

[garrysy]

Thank you for pointing out the Vacuum & Helium. Helium is purging the EDXRF to increase the sensitivity, but for the Vacuum, does this mean the EDXRF is equip with Air & Temperature sensor to compensate and improve the sensitivity?

[marquis]

Some of the systems have a vacuum pump attached to the sample chamber.  Since air attenuates xrays, one way around the attenuation is to pump out all the air.  Some systems offer this as an option.  The problem- if your sample is volatile, it will boil off.  That won't help your analysis or the xray system.

Having said that, a fair number of high molecular weight liquids have very low volatility.  They could handle the vacuum with no problems.

[marquis]

The system we used basically had a GC thermal conductivity detector in it.  It was modified to detect vacuum instead of compounds.  Vacuum is a bad thermal conductor.  They had set go/ no go points in the response curve for acceptable vacuum.