Josh completed a Bachelor’s degree in Aerospace Engineering at the University of Sheffield in 2016. His dissertation project investigated the use of glass fibre composites for self-sensing aerospace components. The project sparked an interest glass science leading Josh to apply for a PhD in nuclear waste immobilisation. Now coming into the final year of his PhD, Josh’s research has concentrated on investigation of caesium volatility using in-situ Raman spectroscopy.
Josh Radford1, Charlie Scales2, Samuel Walling1, Colleen Mann1, Claire L. Corkhill1, Russell J. Hand1 1Immobilisation Science Laboratory, Department of Material Science and Engineering, University of Sheffield, Sir Robert Hadfield Building, Mappin Street, S1 3JD 2National Nuclear Laboratory 5th Floor, Chadwick House, Warrington Road, Birchwood Park, Warrington, WA3 6AE
Quantitative compositional analysis is an invaluable tool to all sectors of glass technology. A number of techniques are used to determine glass compositions. Industrial glass manufacturers commonly use XRF spectroscopy, which for simple glass systems where all the components are detectable using X-Rays, is proven to be a reliable, robust method. However, there certain elements cannot be detected using X-Rays and therefore are undetectable by XRF. Furthermore, for complex glass compositions, matrix effects and signal overlaps must also be taken into account, complicating the analysis. To overcome the matrix effect issues, it is common practise to digest solid glass samples into solution. Once in solution, compositional analysis can be achieved using a number of spectroscopic techniques such as ICP-(MS, MS/MS, OES, AES), Atomic absorption spectroscopy or ion chromatography. Digestion can be achieved using a number of methods, however as with XRF all of these methods have benefits and drawbacks. Three methods of digestion will be discussed; open vessel digestion, alkaline fusion digestion and peroxide fusion digestion. Open vessel digestion is most commonly performed using hydrofluoric acid, which has significant safety concerns surrounding its use. Additionally, for compositions containing rare earth elements (REE), it has been shown that it is difficult to achieve a complete digest of these elements using HF. Therefore, alternative methods are being considered.
This talk will focus on the development of standard digestion procedures using alkaline and peroxide fusions to digest glass samples into solutions suitable for ICP-MS, ICP-OES and ion chromatography. The digestion of a series of standard glass compositions will be discussed, along with the suitability of the different digestion methods for difficult elements (i.e.- silica in HNO3, REE digestion, boron precipitation and volatile losses associated with the fusion process). All samples produced using alkaline and peroxide fusions will be compared to samples digested using HF and to compositions obtained using XRF.