TY - JOUR A1 - Peplinski, Burkhard A1 - Adam, Christian A1 - Adamczyk, Burkart A1 - Müller, Ralf A1 - Schadrack, Reinhard A1 - Michaelis, Matthias A1 - Emmerling, Franziska A1 - Reuther, H. A1 - Menzel, Michael T1 - Evidence of formation of the tridymite form of AlPO4 in some municipal sewage sludge ashes N2 - Evidence is provided that the tridymite component observed in the X-ray diffraction patterns of some sewage sludge ashes (SSAs) should not be interpreted as the tridymite modification of SiO2 but as the tridymite form of AlPO4. This proof is based on a combined X-ray Powder Diffraction (XRD), X-ray fluorescence (XRF) and Mossbauer spectroscopy investigation of two SSAs produced at two fluidized bed incineration facilities, located in different municipalities and operated differently. The structural and chemical characterization was carried out on the 'as received' SSA samples as well as on the residues of these two SSAs pretreated by leaching in citric acid. In addition, direct proof is presented that the tridymite form of AlPO4 does crystallize from X-ray amorphous precursors under conditions that mimic the huge heating rate and short retention time (just seconds at T ≈ 850 °C) typical for fluidized bed incinerators. KW - Aluminium phosphate KW - Ash KW - Fly ash KW - Incinerator ash KW - Sewage sludge ash KW - Tridymite form PY - 2013 U6 - https://doi.org/10.1017/S0885715613000869 SN - 0885-7156 VL - 28 IS - S2 SP - S425 EP - S435 PB - JCPDS CY - Swarthmore, Pa. AN - OPUS4-29703 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -