Analysis of Metals in Refinery Streams Using WDXRF - Laura Oelofse

Metal contaminants in crude oil are common place and often tell the diagensis of the oil released to the earth’s surface. In addition to sulphur, metals such as V, Ni and Fe are indicative of the crude oil’s origins.

Modern refinery processes are sensitive to these metals. In sufficient concentrations they significantly lower the yields of desired products during reaction cycles, and may even poison the catalysts used in these reactions.

Part of the refining process is dedicated to removing these metals from the process streams in order to minimise unwanted side effects. Process control limits exist to maximise refinery process yields and tocontain costs by maximising expensive catalysts lifetimes. Units have a catalyst regeneration cycle need to quantify their effectiveness. Part of the process optimisation requires vigilant analysis of metals in all parts of the refinery streams to meet these process goals.

WDXRF is uniquely suited to be used in these multiple analytical needs, since the steps to prepare samples for analysis are straightforward and relatively quick. The methods can be extremely sensitive, with limits of detection for most metals being of the order of 0.2 - 1.0 ppm, thus allowing quantification of all metals down to 1 - 3ppm.

Rigaku’s ZSX Petro series spectrometers offer both 3 kW and 4 kW options. The Rigaku ultra-thin X-ray tube window allows superior performance for the light elements Na, Mg, Al, Si, P, S, Cl, K and Ca, all of which play a
crucial role in refinery processes performance. Coupled with the Rigaku Scatter FP software, the ZSX Petro spectrometers are uniquely suited to provide accurate standardless analysis for a large number of metal contaminants in a variety of organic matrices. The Scatter FP program accurately models the unmeasured portion of the material being analysed and uses this model in the final refinements of the calculations. The improvement in accuracy utilising this Rigaku software feature over conventional semi-quant programs used in the industry can be as large as 95%.

If better control over the level of refinery metals is a goal of your process refinement, then contact us for a demonstration of this unique approach and let us show you how we can improve your process control.

For more information contact info@rigaku.com, visit our website at www.rigaku.com/xrf/petroleum.html or call us at +1-281-362-2300 and leave a message at x260. Visit us at the Gulf Coast Conference (GCC), booth #904.