Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea

Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea Christian Schreinemachers ID 1,2,3, Olivier Bollen3, and Gregory Leinders ID 2 1Forschungszentrum J¨ ulich GmbH, Institute of Energy and Climate Research, IEK-6: Nuclear Waste Management and Reactor Safety, J¨ ulich, Germany 2Belgian Nuclear Research Centre (SCK CEN), Institute for Nuclear Materials Science, Boeretang 200, B-2400 Mol, Belgium 3KU Leuven, Department of Chemistry, Celestijnenlaan 200F, P.O. Box 2404, B-3001 Heverlee, Belgium Dataset Version: 1.0.0; June 28, 2021 DOI DOI 10.5281/zenodo.3841374 10.5281/zenodo.3841374 License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International Public License. cbn Description The hydrolysis of UO 2+ 2, NdIII, CeIII and CeIV cations, induced by thermal decomposition of urea, was studied. Moreover, we investigated binary mixtures of uranyl and the lanthanides, as well as ternary mixtures of uranyl and both lanthanides using CeIII or CeIV. The impact of the urea content and the temperature on the reaction kinetics and the formed precipitate was evaluated and the results are in depth discussed in our article [1]. Uranyl ions precipitated as ammonium diuranate (ADU) with different stoichiometry under the applied conditions. NdIII and CeIII cations showed a comparable pH evolution during hydrolysis and LnCO3OH products were identified, whereas CeIV hydrolysed at a lower pH and formed nanocrystalline CeO2. Depending on the urea content, a partial co-precipitation was observed for mixtures of UO 2+ 2and NdIII. The products of CeIII and CeIV hydrolysis were also identified in the precipitates of binary uranyl and cerium mixtures. For ternary U/Nd/Ce mixtures, a simultaneous precipitation of NdIII and CeIII and a partial incorporation of the Ln phase into the ADU phase was observed, whereas the presence of CeIV/CeO2resulted in three individual phases. The precipitation reaction was followed-up by monitoring the pH evolution and the metal concentration in the supernatant, applying UV/Vis and ICP-MS. The formed precipitates were characterised by XRD and SEM. The data accrued during the study are part of this data set. Please note that the provision of this dataset is based on a voluntary basis. You are welcome to use the data from this set in your work. If you do so and publish resulting findings, please cite our work as required by the license. Cite as Christian Schreinemachers, Olivier Bollen, & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set]. Zenodo. DOI: 10.5281/zenodo.3841374 BIBT EX key of this dataset: @Misc{Schreinemachers2021_data, author = {Schreinemachers, Christian and Bollen, Olivier and Leinders, Gregory}, title = {Data of uranyl-, {Nd}-, {Ce}-hydrolysis and their mixtures induced by thermal decomposition of urea}, publisher = {Zenodo}, year = {2021}, note = {(Version 1.0.0) [Data set], License: CC BY-NC}, doi = {https://doi.org/10.5281/zenodo.3841374}, } 1 / 30 Contents About this dataset 3 Structure of this dataset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Data processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Hydrolysis experiments 4 Experimental conditions and compositions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1 Reaction follow-up data 7 1.1 Sampling and pH measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1.2 Ultraviolet–visible spectroscopy (UV/Vis) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1.3 Inductive coupled plasma mass spectrometry (ICP-MS) . . . . . . . . . . . . . . . . . . . . . 11 2 Characterisation data of dried precipitates 14 2.1 X-ray powder diffraction (XRD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 2.2 Scanning electron microscopy (SEM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 References 16 Appendix 17 Raw UV/Vis data plots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Reaction follow-up summary plots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Raw X-ray diffraction patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 2 / 30 About this dataset The data are supplement to the following article: C. Schreinemachers et al. “Hydrolysis of uranyl-, Nd-, Ce-ions and their mixtures by thermal decomposition of urea”. In: European Journal of Inorganic Chemistry (2021). DOI:10.1002/ejic.202100453 @Article{Schreinemachers2021, author = {Schreinemachers, Christian and Bollen, Olivier and Leinders, Gregory and Tyrpekl, V´aclav and Modolo, Giuseppe and Verwerft, Marc and Binnemans, Koen and Cardinaels, Thomas}, title = {Hydrolysis of uranyl-, {Nd}-, {Ce}-ions and their mixtures by thermal decomposition of urea}, publisher = {Wiley-VCH Verlag}, journal = {European Journal of Inorganic Chemistry}, year = {2021}, doi = {https://doi.org/10.1002/ejic.202100453}, } Structure of this dataset The dataset was deposited as a compressed zip archive. If the archive is unzipped, subfolders containing the data assigned to the state of the respective folder name are extracted. The folder structure of the extracted dataset can be summarised as presented in figure 1. It has a total size of about 80 MB and all files use the unicode standard UTF-8 for character encoding. dataset 01 precipitation reaction follow-up 02 characterisation dried-precipitates README.pdf license.txt Figure 1: Extracted root folder of this dataset and its content. A description of the data within each subfolder of the datasets’ root folder (figure 1) is given in the corresponding section of this document. Besides the subfolders, there are two files in the root folder, containing information about the dataset itself: 1. README.pdf (this readme file, pdf document) 2. license.txt (license of this dataset, plain text file) Data processing If not stated differently, the were data processed using the Python programming language (Version 3.6.8) [2] in combination with the libraries NumPy (Version 1.16.4) [3] and pandas (Version 0.24.2) [4]. The visualisation of the data was done with gnuplot (Version 5.0.4) and the Python library Matplotlib (Version 3.1.) [5]. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 3 / 30 Hydrolysis experiments The data of this dataset were obtained from samples collected during hydrolysis experiments, which were carried out using the set-up shown in figure 2. The reactions took place in a 100 mL three neck round bottom flask, which was located in a tempered oil bath (see figure 2, close-up). A cooler was attached to the middle neck of the flask and the connected recirculating chiller (Buchi F-105) was set to 9 °C. The solutions’ temperature and the room temperature were measured using thermocouples (temperature range: −200 °C to 1370 °C), connected to a thermometer (Ludwig Schneider Digital-Measuring Instrument 65625), while the temperature of the oil bath was monitored using a stirring plate equipped with a thermocouple (VWR adv. VMS-C7). Figure 2: Photograph of the set-up used for the hydrolysis experiments (left) and a close up of the flask filled with 50 mL uranyl nitrate solution (c(UO2(NO3)2) = 0.05 mol L−1). A volume of 50 mL aqueous solution with an aimed molar metal concentration of 0.05 mol L−1 was given into the flask and the set-up was heated to the desired temperature. Upon reaching a stable temperature, an initial sample of 2 mL was taken using twice a 1 mL pipette (Eppendorf Research Plus, adjustable: 100 µL to 1000 µL). The sampling time and temperatures of the solution and the oil-bath, as well as the room temperature, were noted. Afterwards, solid urea was added to the solution, which dissolved rapidly. The time of urea addition was also noted and used as reference time for further evaluations (trel = 0). During each precipitation reaction, which took up to 10 h, it was sampled every 25 min to 50 min as described for the initial sample. Each sample was stored in a test tube and after reaching temperatures between 25 °C to 29 °C its pH was measured. Besides the pH, the sampleand room-temperature were logged. Afterwards, the sample was given into a 4 mL glass vial with known mass. Further analyses were carried out using ICP-MS and UV/Vis. At the end of the day of each experiment, the second but last sample was taken. The set-up ran during the night and at the following morning (about 25 h since addition of urea), another sample was taken to determine the final pH of the supernatant. Afterwards, the heat source was removed and the set-up was allowed to cool to room temperature. Upon reaching it, the remaining suspension was removed from the flask using a 5 mL pipette (VWR ergonomic high-performance, adjustable: 1 mL to 5 mL). The suspension was distributed evenly between 2 centrifuge vials (Falcon, 15 mL) and centrifuged for 15 min at 6500 rpm. After centrifugation, the Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 4 / 30 supernatant was removed and ultra-pure water was added to each vial. The vials were shaken and centrifuged for antoher 15 min at 6500 rpm. The washing procedure was in total carried out three times. Afterwards, the precipitate was transferred into a 4 mL glass vial and dried at 40 °C and 250 mbar until reaching a stable mass. Precursor solutions Precursor solutions were prepared by dissolving uranyl nitrate, neodymium(III) nitrate, cerium(III) nitrate, and ammonium hexanitratocerate(IV) in ultra-pure water (R≥18.0 MΩ). A volume of 25 mL was prepared for the UO 2+ 2solution, while volumes of 10 mL were prepared for each of the lanthanide cation solutions. The salt was weighed into a volumetric flask of the corresponding volume and filled up with ultra-pure water. Afterwards, the mass was remeasured to calculate the solutions’ density. An overview of the prepared precursor solutions is listed in table 1. It also includes the compound used as starting material, its origin and purity, the mass of the compound, as well as the calculated molar concentration for the metal and the solutions’ density. Table 1: Compound, origin and purity of chemical used to prepare precursor solutions, as well as the masses of the compounds, the molar concentrations based on those masses and the densities of the solutions. Mn+compound origin and purity m(compund)ac(Mn+)ρ(solution) / g / mol L−1 / g mL−1 UO 2+ 2UO2(NO3)2·xH2O prepared from UO2at SCK CENb17.914 56 1.427 1.478 NdIII Nd(NO3)3· 6 H2O Strem Chemicals Inc. (≥99.9 wt%) 2.4039 0.548 1.135 CeIII Ce(NO3)3· 6 H2O Strem Chemicals Inc. (≥99.9 wt%) 0.4603 0.106 1.020 CeIV (NH4)2[Ce(NO3)6] Acros Organics (99.5 wt%, for analysis) 0.5758 0.105 1.041 am(UO2(NO3)2·xH2O) taken using a Mettler Toledo AT201 balance, other compounds weighed on a Sartorius 1712MP8 balance bUO2(NO3)2·xH2O preparation described in our article [1] Further preparations The experimental solution for the three experiments that contained only one lanthanide was generated by weighing the corresponding compound (see table 1) into a 50.00(4) mL volumetric flask and dissolving it in ultra-pure water. All other experimental solutions were prepared by pipetting the appropriate volume of the precursor solution(s) into a 100 mL glass beaker with known mass. The individual precursor solution volumes were calculated based on the aimed molar metal concentration of 0.05 mol L−1, the desired molar metal fractions (listed in table 2), and a total volume of 50 mL of experimental solution, taking the concentrations listed in table 1 into account. After the addition of a precursor solution, the mass was re-measured. The required amount of water was calculated by subtracting the sum of the precursor solution volumes from the desired total volume of 50 mL. We assumed a water density of 1.00 g mL−1 and added the mass corresponding to the calculated volume of water to the beaker. The beaker was placed on a balance and the mass was continuously monitored, the final one was noted down. The urea content is expressed as R(urea), corresponding to the n(urea) n(Mn+)ratio and we used ratios of 26 and 52. All experiments were carried out with aimed molar metal concentrations of 0.05 mol L−1, leading to constant urea masses for each of the urea ratios. For experiments with R(urea) = 26, the aimed mass was 3.7538 g, while it was 7.5075 g for experiments with R(urea) = 52. The urea used in each experiment (Sigma-Aldrich (99.0 % to 100.5 %, ACS reagent) was weighed into a glass beaker and added to the tempered experimental solution after the initial sampling. All data collected during the preparation for each of the experiments, like the pipetted volumes, the corresponding masses, and the urea mass, as well as the addition time are included in this dataset and listed in table 3 (p. 6). The location of the corresponding file (hydrolysis experiments.csv) is indicated in figure 3. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 5 / 30 Experimental conditions and compositions The experimental conditions were adopted from Wangle et al. [6], who investigated the hydrolysis of thorium by thermal decomposition of urea at 90 °C and 100 °C using R(urea) ratios of 5, 25 and 50. In our experiments, we wanted to use constant total molar metal amounts, which required constant masses of urea for each R(urea). We calculated urea contents for R(urea) of 25 and 50, but did not consider that the urea was given into a volume of 48 mL solution instead of 50 mL due to the initial sampling. Taking this into account, our experiments were performed with R(urea) ratios of 26 and 52. An overview of the performed experiments is given in table 2. The table contains the experiment IDs, the aimed molar metal fractions (χ(Mn+) = n(Mn+) Pn(Mn+)) for the cations UO 2+ 2, NdIII, CeIII and CeIV, the aimed urea contents (R(urea) = n(urea) n(Mn+)), as well as the temperatures applied during the experiments. Table 2: ID of hydrolysis experiment, aimed UO 2+ 2, NdIII, CeIII and CeIV molar metal fractions, as well as the aimed molar urea to metal ratio R(urea) and the temperature T. experiment ID aimed molar metal fraction χR(urea) T UO 2+ 2NdIII CeIII CeIV / °C OB-17-01 1.00 26 100 OB-17-02 1.00 26 90 OB-17-03 0.90 0.10 26 90 OB-17-04 1.00 52 90 OB-17-05 0.90 0.10 52 90 OB-17-06 0.75 0.25 52 90 OB-18-01 0.75 0.25 26 90 OB-18-02a1.00 26 90 OB-18-03b0.90 0.10 26 90 OB-18-04 1.00 26 90 OB-18-05 1.00 26 90 OB-18-06 1.00 26 90 OB-18-07 0.80 0.20 26 90 OB-18-08 0.80 0.20 26 90 OB-18-09 0.55 0.25 0.20 26 90 OB-18-10 0.55 0.25 0.20 26 90 arepetition of OB-17-02 brepetition of OB-17-03 Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 6 / 30 1. Reaction follow-up data The data related to the experiment preparations, the hydrolysis conditions, the sampling of the supernatant and the analysis of the samples are located in the subfolder 01 precipitation reaction follow-up of this dataset. It has the content shown in figure 3, which is described underneath. dataset 01 precipitation reaction follow-up 01 reaction follow-up sampling+pH OB-17-01 sample photographs OB-17-01-00.jpg ... OB-17-01 sampling+pH.csv ... 02 reaction follow-up UV-VIS 01 raw UVVIS data OB-17-04 raw UVVIS OB-17-04-00 raw UVVIS.csv ... OB-17-04 raw UVVIS.pdf ... 02 processed UVVIS data OB-17-04 processed UVVIS.csv ... 03 reaction follow-up ICP-MS OB-17-01 ICP-MS.csv ... hydrolysis experiments.csv 02 characterisation dried-precipitates Figure 3: Content of the subfolder for the data belonging to the reaction follow-up of the hydrolysis experiments. The csv file hydrolysis experiments.csv, which is located directly in the subfolder for the reaction follow-up data (01 precipitation reaction follow-up, see figure 3), provides a summary of the performed experiments and contains among others the information listed in table 2. The file is comma separated, its first column lists various keys and the second column an unit where applicable. Each of the remaining column contains data of one specific experiment, which can be assigned to the key of the first column, having the unit mentioned in the second column. The first key, and consequently the first row, contains the experiment ID. All keys and the corresponding unit are listed and described in table 3. The content of the subfolders in the folder 01 precipitation reaction follow-up (see figure 3) is described in the following subsections. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 7 / 30 Table 3: Lists of keys from column 1 and corresponding units from column 2 of the csv file hydrolysis experiments.csv, as well as a brief description of the data for each of the keys. column 1 column 2 description experiment ID ID of the experiment, as listed in table 2 (p. 6) χ(UO22+) aimed aimed UO 2+ 2molar metal fraction, as listed in table 2 (p. 6) χ(Nd(III)) aimed aimed NdIII molar metal fraction, as listed in table 2 (p. 6) χ(Ce(III)) aimed aimed CeIII molar metal fraction, as listed in table 2 (p. 6) χ(Ce(IV)) aimed aimed CeIV molar metal fraction, as listed in table 2 (p. 6) V(U-precursor) / mL pipetted volume of UO 2+ 2precursor solution listed in table 1, (p. 5)a V(Nd-precursor) / mL pipetted volume of NdIII precursor solution listed in table 1 (p. 5)a V(Ce(III)-precursor) / mL pipetted volume of CeIII precursor solution listed in table 1 (p. 5)a V(Ce(IV)-precursor) / mL pipetted volume of CeIV precursor solution listed in table 1 (p. 5)a m(U-precursor) / g mass of V(U-precursor)b m(Nd-precursor) / g mass of V(Nd-precursor)b m(Ce(III)-precursor) / g mass of V(Ce(III)-precursor)b m(Ce(IV)-precursor) / g mass of V(Ce(IV)-precursor)b m(compound) / g mass of solid starting compound listed in table 1 (p. 5)b m(water) / g mass of water added to experimental solutionb T / °C aimed temperature, as listed in table 2 (p. 6) R(urea) aimed aimed n(urea) n(Mn+)ratio, as listed in table 2 (p. 6) m(urea) / g mass of urea (Sigma-Aldrich (99.0 % to 100.5 %, ACS reagent)b urea addition hh:mm time of urea addition vis p start smpl index of first sample where a precipitate was visually recognised vis p end smpl index of first colourless sample, indicating the end of the precipitation vis p start time / min relative sampling time in min of sample with index of vis p start smpl vis p end time / min relative sampling time in min of sample with index of vis p end smpl m(precipitate) dried / g mass of dried precipitatec,d aVolumes pipetted using an adjustable Eppendorf Research Plus pipette (100 µL to 1000 µL). bMasses weighed using a Mettler-Toledo AG204 balance, totaland tara-masses not included. cMasses weighed using a Mettler-Toledo AT201 balance, totaland tara-masses not included. dMass not useful to determine a precipitation yield since the solution was sampled during precipitation. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 8 / 30 1.1. Sampling and pH measurements During the individual hydrolysis experiments, up to 19 samples of the supernatant were taken. The experiment ID was extended with an index as suffix to form sample IDs. The sample taken prior to the addition of urea was extended with -00, leading for example to the sample ID OB-17-01-00. In the case of experiment OB17-01 it was sampled 10 times (OB-17-01-00 to OB-17-01-09) and a photograph of each sample was taken. The photographs are located in the folder OB-17-01 sample photographs (see figure 3) and are named with the corresponding sample ID (e. g. OB-17-01-00.jpg). A collage showing all photographs is presented as figure 4. Figure 4: Samples taken during experiment OB-17-01 (UO 2+ 2,R(urea) = 26, T= 100 °C) with the sample IDs OB-17-01-00 to OB-17-01-09 (left to right). Besides the folder with the photographs of experiment OB-17-01, there exists a csv files for each experiment in the folder 01 reaction follow-up sampling+pH (see figure 3), containing the data related to the sampling and the measured pH values. The csv files (e. g. OB-17-01 sampling+pH.csv, see figure 3) consist of 10 columns, which are comma separated. The column headers indicate the data series of the specific column, which are listed and described in table 4. Table 4: Lists of column headers of the *sampling+pH.csv files (see figure 3), as well as a brief description of the corresponding data and how it was obtained. header description sample ID ID of the sample (experiment ID + running number) time abs / hh:mm:ss absolute sampling time time rel / min relative sampling time in minutes, calculated by subtraction (time abs - ”urea addition”)a Tsolution / °C temperature of solution in °C at moment of sampling, directly measured Toil / °C temperature of oil bath in °C at moment of sampling, directly measured RT sampling / °C room temperature in °C at moment of sampling, directly measured pH pH of the sample, directly measuredb Tsample / °C temperature of sample in °C during pH measurement, directly measured RT measurement / °C room temperature in °C during pH measurement, directly measured m(sample) / g sample mass, calculated by subtraction (m(vial)total - m(vial)tara)c aTime of urea addition listed in hydrolysis experiments.csv (table 3). First and last sample assigned to 0 min and 1500 min, respectively. bMeasured using a WTW pH 3110 pH meter, calibrated daily using pH 4 and pH 7 buffer solutions. cMasses weighed using a Mettler-Toledo AG204 balance, totaland tara-masses not included. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 9 / 30 Acknowledgement The authors thank Koen Vanaken and Peter Dries for laboratory assistance, as well as C´ edric Odeurs for UV/Vis measurements and Prisca Verheyen for ICP-MS analyses. Moreover, we are indebted to the communities behind the multiple open-source software packages which we used. Financial support for this research was provided by the European Commission (project: GENIORS - GEN IV Integrated Oxide fuels Recycling Strategies (755171)), and the Belgian FPS Economy (project: ASOF - Advanced Separation for Optimal management of spent Fuel). References [1] C. Schreinemachers, O. Bollen, G. Leinders, V. Tyrpekl, G. Modolo, M. Verwerft, K. Binnemans, and T. Cardinaels. “Hydrolysis of uranyl-, Nd-, Ce-ions and their mixtures by thermal decomposition of urea”. In: European Journal of Inorganic Chemistry (2021). DOI:10.1002/ejic.202100453. [2] G. van Rossum. Python tutorial. Tech. rep. CS-R9526. Amsterdam: Centrum voor Wiskunde en Informatica (CWI), May 1995. URL:https://ir.cwi.nl/pub/5007/05007D.pdf. [3] T. E. Oliphant. “Python for Scientific Computing”. In: Computing in Science & Engineering 9.3 (2007), pp. 10–20. DOI:10.1109/mcse.2007.58. [4] W. McKinney. “pandas: a foundational Python library for data analysis and statistics”. 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In: Journal of Nuclear Materials 535 (July 2020), p. 152128. DOI:10.1016/j.jnucmat.2020.152128. [13] C. Schreinemachers and G. Leinders. Characterisation data of Ndand Ce-doped uranium dioxide microspheres prepared via internal gelation. (Version 1.0.0) [Data set], License: CC BY-NC. 2020. DOI: 10.5281/zenodo.3560620. [14] J. Schindelin, I. Arganda-Carreras, E. Frise, V. Kaynig, M. Longair, T. Pietzsch, S. Preibisch, C. Rueden, S. Saalfeld, B. Schmid, J.-Y. Tinevez, D. J. White, V. Hartenstein, K. Eliceiri, P. Tomancak, and A. Cardona. “Fiji: an open-source platform for biological-image analysis”. In: Nature Methods 9.7 (June 2012), pp. 676–682. DOI:10.1038/nmeth.2019. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 16 / 30 Appendix Raw UV/Vis data plots 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-17-04-00_raw_UVVIS OB-17-04-01_raw_UVVIS OB-17-04-02_raw_UVVIS OB-17-04-03_raw_UVVIS OB-17-04-04_raw_UVVIS OB-17-04-05_raw_UVVIS OB-17-04-12_raw_UVVIS OB-17-04-13_raw_UVVIS Figure 9: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-17-04. 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-17-05-00_raw_UVVIS OB-17-05-01_raw_UVVIS OB-17-05-02_raw_UVVIS OB-17-05-03_raw_UVVIS OB-17-05-04_raw_UVVIS OB-17-05-05_raw_UVVIS OB-17-05-06_raw_UVVIS OB-17-05-07_raw_UVVIS OB-17-05-08_raw_UVVIS OB-17-05-12_raw_UVVIS Figure 10: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-17-05. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 17 / 30 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-17-06-00_raw_UVVIS OB-17-06-01_raw_UVVIS OB-17-06-02_raw_UVVIS OB-17-06-03_raw_UVVIS OB-17-06-04_raw_UVVIS OB-17-06-05_raw_UVVIS OB-17-06-06_raw_UVVIS OB-17-06-07_raw_UVVIS OB-17-06-08_raw_UVVIS OB-17-06-09_raw_UVVIS Figure 11: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-17-06. 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-18-01-00_raw_UVVIS OB-18-01-01_raw_UVVIS OB-18-01-02_raw_UVVIS OB-18-01-03_raw_UVVIS OB-18-01-04_raw_UVVIS OB-18-01-05_raw_UVVIS OB-18-01-06_raw_UVVIS OB-18-01-07_raw_UVVIS OB-18-01-08_raw_UVVIS OB-18-01-09_raw_UVVIS OB-18-01-10_raw_UVVIS OB-18-01-11_raw_UVVIS OB-18-01-12_raw_UVVIS OB-18-01-13_raw_UVVIS OB-18-01-14_raw_UVVIS OB-18-01-15_raw_UVVIS OB-18-01-16_raw_UVVIS OB-18-01-17_raw_UVVIS Figure 12: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-18-01. 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-18-02-00_raw_UVVIS OB-18-02-01_raw_UVVIS OB-18-02-02_raw_UVVIS OB-18-02-03_raw_UVVIS OB-18-02-04_raw_UVVIS OB-18-02-05_raw_UVVIS OB-18-02-06_raw_UVVIS OB-18-02-07_raw_UVVIS OB-18-02-08_raw_UVVIS OB-18-02-09_raw_UVVIS OB-18-02-10_raw_UVVIS OB-18-02-11_raw_UVVIS OB-18-02-12_raw_UVVIS OB-18-02-16_raw_UVVIS OB-18-02-17_raw_UVVIS Figure 13: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-18-02. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 18 / 30 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-18-03-00_raw_UVVIS OB-18-03-01_raw_UVVIS OB-18-03-02_raw_UVVIS OB-18-03-03_raw_UVVIS OB-18-03-04_raw_UVVIS OB-18-03-05_raw_UVVIS OB-18-03-06_raw_UVVIS OB-18-03-07_raw_UVVIS OB-18-03-08_raw_UVVIS OB-18-03-09_raw_UVVIS OB-18-03-10_raw_UVVIS OB-18-03-11_raw_UVVIS OB-18-03-12_raw_UVVIS OB-18-03-13_raw_UVVIS OB-18-03-18_raw_UVVIS OB-18-03-19_raw_UVVIS Figure 14: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-18-03. 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-18-04-00_raw_UVVIS OB-18-04-01_raw_UVVIS OB-18-04-02_raw_UVVIS OB-18-04-05_raw_UVVIS OB-18-04-10_raw_UVVIS OB-18-04-13_raw_UVVIS OB-18-04-14_raw_UVVIS OB-18-04-15_raw_UVVIS OB-18-04-16_raw_UVVIS OB-18-04-17_raw_UVVIS OB-18-04-18_raw_UVVIS OB-18-04-19_raw_UVVIS Figure 15: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-18-04. 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-18-05-00_raw_UVVIS OB-18-05-01_raw_UVVIS OB-18-05-02_raw_UVVIS OB-18-05-03_raw_UVVIS OB-18-05-04_raw_UVVIS OB-18-05-05_raw_UVVIS OB-18-05-06_raw_UVVIS OB-18-05-07_raw_UVVIS OB-18-05-08_raw_UVVIS OB-18-05-09_raw_UVVIS OB-18-05-10_raw_UVVIS OB-18-05-11_raw_UVVIS OB-18-05-12_raw_UVVIS OB-18-05-13_raw_UVVIS OB-18-05-14_raw_UVVIS OB-18-05-15_raw_UVVIS OB-18-05-16_raw_UVVIS OB-18-05-17_raw_UVVIS OB-18-05-18_raw_UVVIS OB-18-05-18_res_test_raw_UVVIS Figure 16: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-18-05. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 19 / 30 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-18-06-00_1-1000_raw_UVVIS OB-18-06-00_raw_UVVIS OB-18-06-01_raw_UVVIS OB-18-06-02_raw_UVVIS OB-18-06-08_raw_UVVIS OB-18-06-14_raw_UVVIS OB-18-06-15_raw_UVVIS OB-18-06-16_raw_UVVIS OB-18-06-18_1-1000_raw_UVVIS OB-18-06-18_raw_UVVIS Figure 17: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-18-06. 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-18-06_diluted-00_1-100_raw_UVVIS OB-18-06_diluted-01_1-100_raw_UVVIS OB-18-06_diluted-02_1-100_raw_UVVIS OB-18-06_diluted-03_1-100_raw_UVVIS OB-18-06_diluted-08_1-100_raw_UVVIS OB-18-06_diluted-13_1-100_raw_UVVIS OB-18-06_diluted-14_1-100_raw_UVVIS OB-18-06_diluted-15_1-100_raw_UVVIS OB-18-06_diluted-18_1-100_raw_UVVIS Figure 18: Visualisation of the raw UV/Vis data of 1 : 100 diluted samples of experiment OB-18-06. 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-18-07-00_raw_UVVIS OB-18-07-01_1-10_raw_UVVIS OB-18-07-01_raw_UVVIS OB-18-07-02_raw_UVVIS OB-18-07-03_raw_UVVIS OB-18-07-04_raw_UVVIS OB-18-07-04_repetition_raw_UVVIS OB-18-07-05_raw_UVVIS OB-18-07-05_repetition_raw_UVVIS OB-18-07-06_raw_UVVIS OB-18-07-07_raw_UVVIS OB-18-07-08_raw_UVVIS OB-18-07-09_raw_UVVIS OB-18-07-10_raw_UVVIS OB-18-07-11_raw_UVVIS OB-18-07-12_raw_UVVIS OB-18-07-13_raw_UVVIS OB-18-07-14_raw_UVVIS OB-18-07-15_raw_UVVIS OB-18-07-16_raw_UVVIS OB-18-07-17_raw_UVVIS OB-18-07-18_raw_UVVIS Figure 19: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-18-07. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 20 / 30 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-18-08-00_raw_UVVIS OB-18-08-01_raw_UVVIS OB-18-08-02_raw_UVVIS OB-18-08-03_raw_UVVIS OB-18-08-04_raw_UVVIS OB-18-08-05_raw_UVVIS OB-18-08-06_raw_UVVIS OB-18-08-07_raw_UVVIS OB-18-08-08_raw_UVVIS OB-18-08-09_raw_UVVIS OB-18-08-10_raw_UVVIS OB-18-08-11_raw_UVVIS OB-18-08-12_raw_UVVIS OB-18-08-13_raw_UVVIS OB-18-08-14_raw_UVVIS OB-18-08-15_raw_UVVIS OB-18-08-16_raw_UVVIS OB-18-08-17_raw_UVVIS OB-18-08-18_raw_UVVIS Figure 20: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-18-08. 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-18-09-00_raw_UVVIS OB-18-09-01_raw_UVVIS OB-18-09-02_raw_UVVIS OB-18-09-03_raw_UVVIS OB-18-09-04_raw_UVVIS OB-18-09-05_raw_UVVIS OB-18-09-06_raw_UVVIS OB-18-09-07_raw_UVVIS OB-18-09-08_raw_UVVIS OB-18-09-09_raw_UVVIS OB-18-09-10_raw_UVVIS OB-18-09-11_raw_UVVIS OB-18-09-12_raw_UVVIS OB-18-09-13_raw_UVVIS OB-18-09-14_raw_UVVIS OB-18-09-15_raw_UVVIS OB-18-09-17_raw_UVVIS OB-18-09-18_raw_UVVIS Figure 21: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-18-09. 200 250 300 (nm) 0 1 2 3 4 5 Absorption deuterium lamp 400 500 600 700 800 900 (nm) 0.0 0.2 0.5 0.8 1.0 1.2 1.5 1.8 2.0 halogen lamp OB-18-10-00_raw_UVVIS OB-18-10-01_raw_UVVIS OB-18-10-02_raw_UVVIS OB-18-10-03_raw_UVVIS OB-18-10-04_raw_UVVIS OB-18-10-05_raw_UVVIS OB-18-10-06_raw_UVVIS OB-18-10-07_raw_UVVIS OB-18-10-08_raw_UVVIS OB-18-10-09_raw_UVVIS OB-18-10-10_raw_UVVIS OB-18-10-11_raw_UVVIS OB-18-10-12_raw_UVVIS OB-18-10-13_raw_UVVIS OB-18-10-14_raw_UVVIS OB-18-10-15_raw_UVVIS OB-18-10-16_raw_UVVIS OB-18-10-17_raw_UVVIS OB-18-10-18_raw_UVVIS Figure 22: Visualisation of the raw UV/Vis data of the samples taken during experiment OB-18-10. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 21 / 30 Reaction follow-up summary plots 2 4 6 8 pH U (R=26, T=100 °C) visual precipitation 0 20 40 60 c( x ) / mmol L 1 x = U 0 100 200 300 400 500 600 Time / min 0 1 2 c( x ) std . / a. u. Figure 23: Summary of data for samples from experiment OB-17-01. 2 4 6 8 pH U (R=26, T=90 °C) visual start of precipitation, no end noticed 0 20 40 60 c( x ) / mmol L 1 0 100 200 300 400 500 600 Time / min 0 1 2 c( x ) std . / a. u. Figure 24: Summary of data for samples from experiment OB-17-02. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 22 / 30 2 4 6 8 pH U0.9Nd0.1 (R=26, T=90 °C) visual start of precipitation, no end noticed 0 20 40 60 c( x ) / mmol L 1 0 100 200 300 400 500 600 Time / min 0 1 2 c( x ) std . / a. u. Figure 25: Summary of data for samples from experiment OB-17-03. 2 4 6 8 pH U (R=52, T=90 °C) visual precipitation 0 20 40 60 c( x ) / mmol L 1 x = U 0 100 200 300 400 500 600 Time / min 0 1 2 c( x ) std . / a. u. x = U Figure 26: Summary of data for samples from experiment OB-17-04. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 23 / 30 2 4 6 8 pH U0.9Nd0.1 (R=52, T=90 °C) visual precipitation 0 20 40 60 c( x ) / mmol L 1 x = U x = Nd 0 100 200 300 400 500 600 Time / min 0 1 2 c( x ) std . / a. u. x = U x = Nd Figure 27: Summary of data for samples from experiment OB-17-05. 2 4 6 8 pH U0.75Nd0.25 (R=52, T=90 °C) visual precipitation 0 20 40 60 c( x ) / mmol L 1 x = U x = Nd 0 100 200 300 400 500 600 Time / min 0 1 2 c( x ) std . / a. u. x = U x = Nd Figure 28: Summary of data for samples from experiment OB-17-06. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 24 / 30 2 4 6 8 pH U0.75Nd0.25 (R=26, T=90 °C) visual precipitation 0 20 40 60 c( x ) / mmol L 1 x = U x = Nd 0 100 200 300 400 500 600 Time / min 0 1 2 c( x ) std . / a. u. x = U x = Nd Figure 29: Summary of data for samples from experiment OB-18-01. 2 4 6 8 pH U (R=26, T=90 °C) visual precipitation 0 20 40 60 c( x ) / mmol L 1 x = U 0 100 200 300 400 500 600 Time / min 0 1 2 c( x ) std . / a. u. x = U Figure 30: Summary of data for samples from experiment OB-18-02. Christian Schreinemachers, Olivier Bollen & Gregory Leinders. (2021). Data of uranyl-, Nd-, Ce-hydrolysis and their mixtures induced by thermal decomposition of urea (Version 1.0.0) [Data set], License: cbn . Zenodo. DOI: 10.5281/zenodo.3841374 25 / 30