In our previous research the accuracy, precision and uncertainty of wavelength dispersive X-ray fluorescence (XRF) spectroscopy measurements of biomass materials was assessed. Thirteen biomass certified reference materials were analyzed as well as five common energy fuels (woods, grasses, etc.) where ICP-MS results were used to determine the accuracy of the results from XRF. The XRF results were found to be give reliable information on the inorganic compositions of the biomass samples. Relative errors were typically less than +/- 15% of the certified values and the results from ICP. The XRF measurements were made on the whole biomass samples, i.e. there was no need to ash the samples before analysis. In the current research, XRF spectroscopy was used to assess the effectiveness of various mild pretreatment methods for improving the fuel quality of banagrass, a tropical grass. Three types of pretreatment were used with increasing levels of severity, i) S1 involves de-watering (pressing) only, ii) S3# where the sample is pressed and leached, and iii) S3 where pressing-leaching-pressing process is used. In addition, the influence of particle size (2 mm or 60-80 mm), leaching water temperature (25 or 75 °C) and time (1 or 3 minutes) on the extraction of inorganic elements was examined. The results show that the S3 pretreatment is the most effective and that reducing the particle size has a more significant effect than increasing leaching temperature or time. Using a 2 mm particle size at 75 °C for 3 minutes produced the greatest effect, removing 50-60 wt% of the Na, ~65 wt% Mg, ~90 wt% P, ~90 wt% K, ~55 wt% S, and ~95 wt% Cl. Using de-watering alone (S1) to pretreat the banagrass was the least effective approach. The S3# pretreatment produced results that are midway between the S1 and S3 results; however using small particle with the S3# method gives similar results to processing large particle using the S3 approach. Preliminary results from the XRF analysis of a range of tropical biomass species and charcoals produced using constant volume pyrolysis will also be presented.

XRF analysis of water pretreated/leached banagrass to determine the effect of temperature, time and particle size on the removal of inorganic elements

253rd National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.