XOS were showing their Petra MAX D4294 analyser at Pittcon and we reported on this in issue 29/2. The production version has now been released with some significant performance improvements. Petra MAX offers combined analysis of 13 elements from P to Zn, with high-precision (5.7 ppm) sulphur analysis in addition to rapid monitoring of elements like Ca, Fe, K, Ni and V at sub-ppm levels. Test methods for measuring sulphur content, like ASTM D4294 and ISO 8754, have become critical for assessing the value of crude oil. Petra MAX is based on XOS’ patented high definition X-ray fluorescence, which uses doubly curved crystal optics coupled with a high-performance silicon drift detector and an intense monochromatic excitation beam. This reduces background noise and increases signal-to-noise output, enabling low detection limits and high precision without the need for consumable helium gas, a vacuum pump or extensive sample preparation.