TY - JOUR A1 - Kervarec, M.-C. A1 - Kemnitz, E. A1 - Scholz, G. A1 - Rudic, S. A1 - Jäger, Christian A1 - Braun, T. A1 - Michalchuk, Adam A1 - Emmerling, Franziska T1 - A HF Loaded Lewis-Acidic Aluminium Chlorofluoride for Hydrofluorination Reactions N2 - The very strong Lewis acid aluminium chlorofluo-ride (ACF) was loaded with anhydrous HF. The interactionbetween the surface of the catalyst and HF was investigatedusing a variety of characterization methods, which revealed he formation of polyfluorides. Moreover, the reactivity ofthe HF-loaded ACF towards the hydrofluorination of alkyneswas studied. KW - Aluminium KW - HF KW - Hydrofluorination KW - Metal fluorides PY - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-508360 VL - 26 SP - 1 PB - Wiley Online Libary AN - OPUS4-50836 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Adam, Christian A1 - Herzel, Hannes A1 - Stemann, Jan A1 - Hermann, Ludwig A1 - Krüger, Oliver T1 - A thermochemical process for fertilizer production from sewage sludge ashes investigated from lab to industrial scale N2 - Sewage sludge ashes (SSA) contain up to 13% P and are thus promising raw materials for fertilizer production. However, SSAs also contain heavy metals and the main P-bearing mineral phases whitlockite and aluminium phosphate are poorly bioavailable. We developed and patented a process that produces fertilizers from SSA addressing the above mentioned challenges. SSA is thermo-chemically treated at ~950°C under reducing conditions (reductive: dry sewage sludge) in a rotary kiln together with an alkali compound such as sodium or potassium sulfate, hydroxide or carbonate. Some undesired trace elements such as As, Hg, Pb and Cd are evaporated and separated via off gas treatment system. The poorly soluble phosphates are transformed into calcium alkali phosphates (CaNaPO4 or CaKPO4) that are not water soluble but completely soluble in neutral ammonium citrate solution (NAC). Pot experiments showed that the fertilizer performance of the treated SSA containing calcium alkali phosphates as the single P-bearing mineral phase was comparable to the performance of triple superphosphate. The PNAC-solubility of fertilizer products correlated very well with the resulting contents of calcium alkali phosphates and the P-uptake of plants in pot experiments. The effect of the ratio alkali/P on the PNAC-solubility was investigated by crucible experiments and trial series with a medium scale rotary kiln using different SSAs and alkali phosphates. The effects of operational parameters such as the temperature and the retention time were investigated as well as concurring side reactions of the alkali compounds e.g. with SiO2 present in SSA. The alkali/P ratio must be roughly adjusted at 2 to achieve 100% PNAC-solubility for a common type of SSA. A demonstration trial with an output of 2 t recycling fertilizer was carried out in an industrial rotary kiln (product output 30 kg/h). The PNAC-solubility of the product varied between 60% and 80% during the 4 days campaign showing that the transformation of the mineral P-phases to calcium alkali phosphates was not complete. This was observed although the amount of Na2SO4 additive was dosed according to the results of the pre-investigations. Structure analysis by XRD showed that besides the target compound CaNaSO4 also some Ca3(PO4)2 remained in the SSA as well as some unreacted Na2SO4 additive. Obviously, the conditions in the industrial rotary kiln were not optimal for the process showing that some process aspects have to be reconsidered for the scale-up. T2 - IPW8 - 8th International Phosphorus Workshop CY - Rostock, Germany DA - 12.09.2016 KW - Sewage sludge ash KW - Thermochemical treatment KW - Phosphorus recovery PY - 2016 AN - OPUS4-37375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weimann, Karin A1 - Adam, Christian T1 - Advantages of recycling gypsum plasterboards N2 - During the last decades the material composition of buildings has become increasingly diverse. However, largely sorted material flows are needed for generating high quality secondary building materials. The use of secondary building materials can meet the requirements of sustainability in several ways: the extended time availability of primary raw materials and, thereby, the preservation of natural resources as well as the conservation of landfill sites. Recycling of gypsum (calcium sulfate) can be a good example for the environmental benefits of closed-loop recycling. The content of sulfates in other secondary building materials, in particular in recycled concrete aggregates, should be minimized for quality reasons. In contrast, separated gypsum can also be used in gypsum production if the high quality requirements for the recycled gypsum are met. Since almost all processing steps in the recycling process are associated with environmental impacts, an environmental evaluation of the use of recycled gypsum as a substitute in gypsum production has to be carefully conducted. This paper focusses on the techniques for generating recycled gypsum from gypsum plasterboards, the related quality requirements and a comprehensive environmental evaluation of the complete process. T2 - IV International Conference Progress of Recycling in the Built Environment CY - Lisbon, Portugal DA - 11.10.2018 KW - Environmental evaluation KW - CDW processing KW - Gypsum PY - 2018 AN - OPUS4-48079 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kratz, S. A1 - Vogel, Christian A1 - Adam, Christian T1 - Agronomic performance of P recycling fertilizers and methods to predict it: a review N2 - Phosphorus (P) is an essential element for all life forms, and P-availability thus an important driver of a functioning agriculture. However, phosphate rock resources for P-fertilizer production are only available in a few countries. Therefore, P-recovery from waste materials has become of increasing interest during the last decade and has been investigated worldwide. In order to characterize potential novel P-fertilizers made from recycled materials, a large array of P-compound characterizations, chemical extractions and growth experiments were performed. This review bundles the work carried out in that field over the last years. Overall, P-fertilizers from recycled materials show a broad range of P-compounds with very different chemical structure and solubility. Growth experiments performed to assess their fertilizing effects display high variations for most of the products. While these experiments have demonstrated that some fertilizers made of recycled materials may reach P effects in the same order of magnitude as water-soluble phosphate rock-based fertilizers, an important limitation in their interpretation is the fact that they often vary considerably in their experimental design. The existing data show clearly that standardization of growth experiments is urgently needed to achieve comparable results. Standard chemical extractants used to assess the chemical solubility of P-fertilizers were found to be of limited reliability for predicting plant P uptake. Therefore, alternative methods such as sequential fractionation, or the extraction of incubated soil/fertilizer mixtures with standard soil extractants or with P sink methods should be tested more intensively in the future to provide alternative options to predict the P-availability of fertilizers from recycled materials. KW - Recycling fertilizer KW - Phosphorus KW - Chemical extraction methods KW - Agronomic performance KW - Incubated soil/fertilizer mixtures KW - P sink method KW - Diffusive gradients in thin films (DGT) PY - 2019 U6 - https://doi.org/10.1007/s10705-019-10010-7 SN - 1385-1314 SN - 1573-0867 VL - 115 IS - 1 SP - 1 EP - 39 PB - Springer AN - OPUS4-48713 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Hermann, P. A1 - Kästner, B. A1 - Adamczyk, Burkart A1 - Hoehl, A. A1 - Ulm, G. A1 - Adam, Christian T1 - Air and chlorine gas corrosion of different silicon carbides analyzed by nano-Fourier-transform infrared (nano-FTIR) spectroscopy N2 - The present study shows the potential of high-resolution imaging and nano-Fourier-transform infrared (nano-FTIR) spectroscopy for corrosion science. The protective oxidation layers of different chlorine-gas treated silicon carbides (SiCs) were characterized with these techniques. A nitrified SiC showed the highest resistant strength against chlorine corrosion at 1000 °C compared to the other SiCs. Nano-FTIR spectroscopy with a lateral resolution below 40 nm detected differences in the crystallinity of the bulk-SiC and in the transitional region to the protective layer. Furthermore, high-resolution imaging provides deep insight in the interfacial layer between bulk-SiC and the protective oxidation layer on sub-micrometer scale. KW - Nano-Fourier-transform infrared spectroscopy KW - Scattering-type scanning near-field optical microscopy (s-SNOM) KW - Synchrotron radiation KW - Corrosion KW - Silicon carbide KW - Chlorine PY - 2018 U6 - https://doi.org/10.1016/j.corsci.2017.12.002 SN - 0010-938X VL - 131 SP - 324 EP - 329 PB - Elsevier AN - OPUS4-43648 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Adam, Christian T1 - Case study 2 - Recovery of phosphorus from sewage sludge ashes T2 - Resources that don't cost the earth Workshop CY - Berlin, Germany DA - 2011-12-01 KW - Resources KW - Phosphorus recovery PY - 2011 SP - 17 AN - OPUS4-26930 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Adam, Christian A1 - Krüger, O. T1 - Challenges in analysing rare earth elements in different waste matrices to determine recovery potentials N2 - The rare earth elements (REEs) are a group of 17 elements from the lanthanide series including scandium and yttrium that share similar physical and chemical properties. They are progressively important for transition to a green, low-carbon economy due to their vital role in electric cars, permanent magnets, fluorescent lamps, rechargeable NiMH batteries, catalysts and other applications. In reality, the term “rare” is misleading as these elements are widely present in the earth’s crust. However, even if not rare, REEs have a high supply risk due to the geopolitical situation e.g. resulting from limited Chinese exports. This, along with their importance in various clean and high-tech applications, has led the EU and the U.S. to label certain REEs, especially europium, terbium and yttrium as critical elements. Recycling is often considered as one of the ways to reduce REEs criticality, especially the import dependency. A recycling strategy for REE requires reliable analytical data of different types of waste streams. The REE bearing waste matrices can be completely different depending on its origin. Digestion methods prior to ICP-OES / -MS analysis must be optimized for the different matrices to guarantee reliable results. We present two examples of different REE bearing waste streams - fluorescence lamp shredder waste and red mud - and show how the analytical procedures were optimized. T2 - ERES 2017: 2nd European Rare Earth Resources Conference CY - Santorini, Greece DA - 28.05.2017 KW - Rare earth elements KW - Digestion methods KW - Waste materials PY - 2017 AN - OPUS4-43305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Ramsteiner, M. A1 - Sekine, R. A1 - Doolette, A. A1 - Adam, Christian T1 - Characterization of phosphorus compounds in soils by deep ultraviolet (DUV) Raman microspectroscopy N2 - Deep ultraviolet Raman microspectroscopy was successfully investigated as a new approach to analyze the chemical state of phosphorus compounds directly in soil. We demonstrate that ultraviolet excitation has the advantage to avoid the interference with the strong fluorescence, which occurs in the visible spectral range caused by organic matter in soils. Furthermore, the spatial resolution of <1 μm2 enables the detection of very small phosphorus particles. For some organic phosphorus compounds (β-glycerophosphate, aminomethylphosphonic acid), sample cooling to -100 °C is found to strongly reduce the rate of degradation induced by the illumination with the ultraviolet excitation light. However, phytic acid and adenosine monophosphate degraded even with cooling. Our results reveal the capability of deep ultraviolet Raman microspectroscopy as a high-resolution benchtop imaging technique for the analysis of local interactions between soil compounds with the potential to become an analytical key to improve the understanding of transformation mechanisms of phosphates as well as other mineral phases in soils. KW - Phosphorus speciation KW - Deep ultraviolet (DUV) Raman microspectroscopy KW - Soil PY - 2017 U6 - https://doi.org/10.1002/jrs.5115 SN - 0377-0486 VL - 48 IS - 6 SP - 867 EP - 871 PB - Wiley AN - OPUS4-40508 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Adam, Christian A1 - Peplinski, Burkhard A1 - Wellendorf, Stephan T1 - Chemical reactions during the preparation of P and NPK fertilizers from thermochemically treated sewage sludge ashes KW - NPK fertilizer KW - P fertilizer KW - Phosphorus recycling KW - Sewage sludge ash KW - Urban mining PY - 2010 U6 - https://doi.org/10.1111/j.1747-0765.2010.00485.x SN - 0038-0768 SN - 1747-0765 VL - 56 IS - 4 SP - 627 EP - 635 PB - Blackwell Publ. Asia CY - Tokyo, Japan AN - OPUS4-21924 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Adam, Christian A1 - Kappen, P. A1 - Schiller, T. A1 - Lipiec, E. A1 - McNaughton, D. T1 - Chemical state of chromium in sewage sludge ash based phosphorus-fertilisers N2 - Sewage sludge ash (SSA) based P-fertilisers were produced by thermochemical treatment of SSA with Cl-donors at approximately 1000 °C. During this thermochemical process heavy metals are separated as heavy metal chlorides via the gas phase. Chromium cannot be separated under normal conditions. The risk of the development of toxic Cr(VI) during the thermochemical process was investigated. X-ray Absorption Spectroscopy measurements showed that SSA and thermochemically treated SSA with CaCl2, MgCl2 and NaCl contain Cr(III) compounds only. In contrast, treating SSA with elevated quantities of Na2CO3, to enhance the plant-availability of the phosphate phases of the fertiliser, developed approximately 10–15% Cr(VI). Furthermore, Raman microspectroscopy showed that using Mg-carbonate reduces the risk of a Cr(VI) development during thermochemical treatment. Additionally, leaching tests showed that only a Cr–water solubility >10% is an indicator for Cr(VI) in SSA based P-fertilisers. KW - Chromium KW - Fertiliser KW - Sewage sludge ash KW - Raman microspectroscopy KW - X-ray absorption spectroscopy PY - 2014 U6 - https://doi.org/10.1016/j.chemosphere.2013.12.012 SN - 0045-6535 SN - 0366-7111 VL - 103 SP - 250 EP - 255 PB - Elsevier Science CY - Kidlington, Oxford AN - OPUS4-30062 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -