Study of sediment samples using instrumental photon activation multi-elemental analysis

Instrumental Photon Activation Analysis (IPAA) has been used in many fields including environmental geochemistry. In the analysis of soil and sediment samples, the sensitivity of IPAA is comparable to that of standard methods such as atomic absorption spectroscopy. A major advantage of IPAA is that minimal sample processing is required and multi-element analyses can be obt ained. In this work, the method of Internal Standard Coupled with Standard Addition Method (ISM-SAM) was applied to IPAA analysis of sediment samples. The equation used in ISM-SAM was derived in detail and the relationship be tween the elemental mass and the gamma peak counts in the measured spectra was established. II was found that accurate results can be obtained even wh en the sample and the reference are irradiated at different photon fluxes a nd measured in different geometries. The ISM SAM equation was refined to be tter quantify the relationship between the addition amount and the uncertai nty. Applying refined ISM-SAM, a sediment sample from Hudson River was anal yzed. The concentrations of Ni, Po, Zr, Ca, Fe, Mg, Na, Ti, As, Cr, Ce, Co, Rb, and Zn were determined and compared with the results obtained from Ato mic Absorption analysis of total acid digests. For elements analyzed by bot h methods, excellent agreement was found. Meanwhile, the detection limits o f photon activation analysis for selected elements were obtained based on t he present experimental conditions.