A new generation of ED-XRF technology for petroleum analysis applications 

Rigaku has launched the new NEX CG II XRF analyser, which they claim will push the boundaries of ED-XRF analysis thanks to its integral closed-coupled Cartesian Geometry optical kernel. The new analyser performs fast, non-destructive multi-elemental analysis of Sodium (Na) to Uranium (U) from ultra-low and trace levels to percentages. 

The new instrument is the second generation of Rigaku’s highly successful NEX CG which is renowned for its versatility, flexibility and high sensitivity and is ubiquitous in petroleum and petrochemical labs worldwide. Rigaku have always listened to their customers’ needs and the NEX CG II was designed to take XRF analysis in the petroleum lab to the next level. 

The NEX CG takes a different approach to ED-XRF analysis. Rigaku have devised an indirect excitation system that uses secondary targets rather than tube filters. Monochromatic and polarised excitation from secondary targets in full 90° Cartesian Geometry completely removes background noise thus facilitating remarkably low detection limits, even with the most trying samples. 

Rigaku’s new and highly versatile multi-element analyser can perform a multitude of applications in a petroleum lab. For example: operators can simultaneously measure sulphur and chlorine from a single sample pour, or simultaneously measure nickel, sulphur, vanadium and iron – or monitor for ultra-low levels of sulphur in diesel and petroleum products, or monitor for trace elements in crude, lubricants, waste oil and cutting fluid. 

This unit is ideal for compliance to ASTM and other global regulatory bodies’ methods for ultra-low sulphur applications, including testing ultra-low sulphur in diesel (ULSD) and reaching Tier 3 gasoline requirements according to ASTM D7220. NEX CG II performs the lowest chlorine detection limits for ASTM D4929 using Part C methodology and makes easy work for ASTM D5059 Parts A & C using the bi- internal standard method to monitor lead in gasoline samples. 

NEX CG II is simple enough for non-technical operators but powerful enough for experienced operators in commercial laboratories and R&D facilities. It features stronger analytical power with its 50 kV 50 W end-window palladium-anode X-ray tube, five secondary targets as well as a large-area high-throughput silicon drift detector (SDD). This unique optical kernel, along with Rigaku’s cutting edge RPF-SQX Fundamental Parameters software, provides the petroleum sector with an unsurpassed level of ED-XRF sensitivity. 

NEX CG II is easy to use with QuantEZ^®, the powerful PC-based software offering intuitive instrument control and simple menu navigation as well as a customisable EZ Analysis interface. Operators can maximise time and productivity by running simplified routine operations and creating their own methods by utilising a user-friendly flow bar wizard. 

The RPF-SQX Fundamental Parameters Software, with Rigaku Profile Fitting (RPF) technology and Scattering FP powers both advanced qualitative and quantitative analysis. The integrated software enables semi-quantitative analysis of virtually all sample types without standards and quantitative analysis with standards.  The concentration of unmeasurable low atomic number elements (hydrogen to fluorine) is estimated automatically with the requisite corrections by the Rigaku Scattering FP method. 

The RPF-SQX requires far less calibration standards than conventional ED XRF systems. This reduces expense and cost of ownership considerably whilst eliminating the hassle of sourcing these standards and running tedious routine analyses.