TY - CONF A1 - Fritzsche, Lutz A1 - Knorr, Annett ED - Cozzani, V. ED - de Rademaeker, E. T1 - Specification of the limit temperature Texo for a peroxide synthesis using different estimation methods N2 - A major item of thermal process safety, concerning the industrial realisation of exothermic reactions, is the determination of a temperature, where a reaction can be carried out without risk for humans, environment, and of economic loss. The so-called limit temperature Texo is a safety parameter for the reaction process and should not be mixed up with the Self Accelerating Decomposition Temperature (SADT). The last one refers to a temperature value for safe transportation including specific conditions like transport time and type of containment. In Germany a technical guide (Identification and Control of Exothermic Chemical Reactions, TRAS 410, 2012) specifies three approaches for determining Texo. In this work, all these approaches were applied to specify Texo for the synthesis of three tert-Butyl peroxycarboxylic esters. Peroxycarboxylic esters are a subdivision of organic peroxides, known for their high hazardous potential. Results differed partly significant. Anyhow, all of the used techniques and evaluation methods led to Texo values, which were on the safe side – taken the Texo value estimated by the heat release criterion as reference. This method is considered by the authors as a very accurate one. T2 - CISAP-6 - 6th International Conference on Safety and Environment CY - Bologna, Italy DA - 13.04.2014 KW - Peroxide KW - TRAS410 KW - Process safety PY - 2014 SN - 978-88-95608-27-3 DO - https://doi.org/10.3303/CET1436021 SN - 2283-9216 N1 - Serientitel: Chemical engineering transactions – Series title: Chemical engineering transactions IS - 36 SP - 121 EP - 126 PB - AIDIC, Associazione Italiana di Ingegneria Chimica CY - Milano AN - OPUS4-30618 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Guillaume, F. A1 - Knorr, Annett A1 - Rotureau, P. T1 - First QSPR models to predict the thermal stability of potential self-reactive substances N2 - Self-reactive substances are unstable chemical substances which can easily decompose and may lead to explosion in transport, storage, or process situations. For this reason, their thermal stability properties are required to assess possible process safety issues and for classification purpose. In this study, the first quantitative structure–property relationships (QSPR) dedicated to this class of compounds were developed to predict the heat of decomposition of possible self-reactive substances from their molecular structures. The database used to develop and validate the models was issued from a dedicated experimental campaign on 50 samples using differential scanning calorimetry in homogeneous experimental conditions. QSPR models were derived using the GA-MLR methods (using a genetic algorithm and multi-linear regressions) using molecular descriptors calculated by Dragon software based on two types of inputs: 3D molecular structures determined using the density functional theory (DFT), allowing access to three-dimensional descriptors, and from SMILES codes, favoring the access to simpler models, requiring no preliminary quantum chemical calculations. All models respected the OECD validation guidelines for regulatory ac ceptability of QSPR models. They were tested by internal and external validation tests and their applicability domains were defined and analyzed. KW - Self-reactive substances KW - Quantitative Structure-Property Relationships KW - Thermal stability KW - Genetic algorithm PY - 2022 DO - https://doi.org/10.1016/j.psep.2022.05.017 SN - 0957-5820 VL - 163 SP - 191 EP - 199 PB - Elsevier Ltd. AN - OPUS4-55631 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schwarz, Silke A1 - Knorr, Annett A1 - Lohrer, Christian T1 - Screening of hexachlorobenzene (HCB) contents in fireworks N2 - This paper gives a brief overview of the findings of hexachlorobenzene (HCB) in fireworks compositions observed within EC type-examinations according to Module B (as set out in the annex II of the Directive 2007/23/EC) of the notified body BAM. In this work, roughly 220 samples were analysed, originating from 49 consumer fireworks articles of the category F2, such as batteries, combinations, fountains and rockets. It was found that the vast majority of samples showed concentrations below 5 mg HCB/kg. However, in three cases concentration values between 5 mg HCB/kg and 50 mg HCB/kg werre observed, and in a further four cases extreme values of up to 8046 mg HCB/kg were detected. The results of this study are compared with published HCB findings originating from market surveillance activities in Europe. KW - Consumer fireworks KW - Forbidden substances KW - Pyrotechnic articles PY - 2014 SN - 1082-3999 IS - 33 SP - Article 0103, 3 EP - 8 CY - Whitewater, Colo. AN - OPUS4-30758 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Knorr, Annett A1 - Krebs, Holger T1 - Testing of DNT and TNT by the mini-autoclave method N2 - Autoclave methods are commonly used when pressure progress under thermal stress is of interest. One of them is the mini-autoclave method by Kühner AG. To test the robustness of the equipment under powerful exposure, two known high energetic materials, DNT and TNT, were investigated. The sample mass was increased stepwise in the range from 0.25 g to 1.0 g. For one test (1 g TNT), gas burners instead of the usually employed 2-zone heating block, were used to intensify the test conditions. Results showed the expected slower pressure generation of DNT in comparison to TNT. The mechanical robustness of the apparatus could be approved in all runs. Pressure data were used to calculate the energy release of decomposition. The values were in good agreement with the heat of decomposition, estimated by DSC. KW - Autoclave KW - DNT KW - TNT KW - Decomposition KW - Energy PY - 2014 DO - https://doi.org/10.1002/prep.201300090 SN - 0721-3115 SN - 0340-7462 SN - 1521-4087 VL - 39 IS - 4 SP - 580 EP - 585 PB - Wiley-VCH CY - Weinheim AN - OPUS4-31207 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Knorr, Annett T1 - Prediction of SADT – requirements for simple and complex correlations N2 - Topic of the presentation is the predictability of safety characteristics like the Self Accelerating Decomposition Temperature (SADT) by means of simple correlations from DSC measurements or by models, which incorporate amongst others the molecular structure of the considered compound. Already existing models of quantitative structure-property relationship (QSPR) for SADT determination suffer from test results, which are, on the majority, not comprehensible. The quality of the generated models is questionable. One item within the Safera-project is the provision of reliable data to have a solid basis for the prediction. T2 - Safera-Workshop "Predictive methods for determining the decomposition properties of hazardous substances" CY - Ostrava, Czech Republic DA - 23.11.2016 KW - SADT KW - Prediction methods PY - 2016 AN - OPUS4-40192 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fritzsche, Lutz A1 - Knorr, Annett T1 - Calorimetric study of peroxycarboxylic ester synthesis N2 - Exothermic reactions involving organic peroxides carry a high potential hazard and must be considered with care. A safe handling requires, among others, the assessment of thermal process safety, for which safety characteristics like overall heat production and the resulting adiabatic temperature rise are essential. The article presents the results of the calorimetric investigation of the synthesis of four peroxycarboxylic esters, three tert-Butyl and one tert-Amyl peroxycarboxylic ester. In the two-step synthesis the second one clearly shows the higher exothermic potential. The overall heat production lies in the range of 126–135 kJ/mol and is nearly independent of the carboxylic acid residual in the tert-Butyl peroxycarboxylic ester. The calculated adiabatic temperature rise is 70–80 K. Influence of temperature and feed rate on the heat generation is discussed for one species. A grading of the synthesis with respect to temperature levels according to the criticality classes by Stoessel leads to the most critical for an exothermic reaction. KW - Reaction calorimetry KW - Organic peroxide KW - Peroxycarboxylic ester KW - Process safety PY - 2009 DO - https://doi.org/10.1016/jhazmat.2008.07.032 SN - 0304-3894 VL - 163 IS - 2-3 SP - 1403 EP - 1407 PB - Elsevier CY - Amsterdam AN - OPUS4-18943 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wehrstedt, Klaus-Dieter A1 - Knorr, Annett A1 - Schuurman, P. T1 - The "Mini Closed Pressure Vessel Test (MCPVT)" as a screening or classification test for explosive properties of organic peroxides N2 - Tests according to the UN Recommendations on the Transport of Dangerous Goods for the determination of explosive properties of organic peroxides have been compared with screening criteria for explosivity based on measurements in a closed mini-autoclave (MCPVT). It will be shown that an additional screening test may be helpful but the information obtained from the UN tests are more important to characterise the specific properties of a substance under different conditions. KW - MCPVT KW - Organic peroxides KW - UN Manual of Tests and Criteria KW - Explosive properties PY - 2003 DO - https://doi.org/10.1016/j.jlp.2003.08.001 SN - 0950-4230 SN - 1873-3352 VL - 16 SP - 523 EP - 531 PB - Butterworth CY - Guildford, Surrey AN - OPUS4-2699 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schreck, Andreas A1 - Knorr, Annett A1 - Wehrstedt, Klaus-Dieter A1 - Wandrey, Peter-Andreas A1 - Gmeinwieser, T. A1 - Steinbach, J. T1 - Investigation of the explosive hazard of mixtures containing hydrogen peroxide and different alcohols N2 - The explosive properties of mixtures of aqueous hydrogen peroxide (H2O2) and different alcohols (R–OH) like 2-propanol (2-PropOH), 2-methyl-2-propanol (TBA), 2-methyl-2-butanol (TAA) and 2-methyl-2-pentanol (THA) were investigated. Among others, the potential hazard of such mixtures may be characterized by their ability to react by different mechanisms of an explosion in the condensed phase, e.g. the thermal explosion or the detonation. Accordingly, the mixtures were experimentally investigated either by heating them up under confinement in different autoclaves or by exposing them to a shock wave impact applying the steel tube test. The results are discussed and compared to literature data. KW - Mixtures of hydrogen peroxide and alcohols KW - Explosive properties KW - Steel tube test KW - TEVT KW - MCPVT PY - 2004 DO - https://doi.org/10.1016/j.jhazmat.2004.01.003 SN - 0304-3894 VL - 108 IS - 1-2 SP - 1 EP - 7 PB - Elsevier CY - Amsterdam AN - OPUS4-3535 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Knorr, Annett A1 - Koseki, H. A1 - Li, X.-R. A1 - Tamura, M. A1 - Wehrstedt, Klaus-Dieter A1 - Whitmore, M. W. T1 - A closed pressure vessel test (CPVT) screen for explosive properties of energetic organic compounds N2 - Results of a round-robin test on a mini-autoclave are reported and previously proposed criteria reviewed. Criteria based upon the results for three standard materials are now put forward. These standards-based criteria, in contrast to numerical criteria, theoretically allow any laboratory to utilize the data accumulated to date, irrespective of the equipment used. The practical requirement is that adequate discrimination can be achieved. Data to assess this are given. KW - Closed pressure vessel test KW - Mini-autoclave KW - MCPVT KW - Explosive properties PY - 2007 SN - 0950-4230 SN - 1873-3352 VL - 20 IS - 1 SP - 1 EP - 6 PB - Butterworth CY - Guildford, Surrey AN - OPUS4-14385 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fritzsche, Lutz A1 - Knorr, Annett T1 - Transformation of the 2nd step of a peroxyester synthesis from semi-batch to continuous mode N2 - Organic peroxides are known for their decomposition behaviour and for considerable heat release connected with pressure build up. Efforts are required to run the industrial synthesis in semi-batch mode on safe condition. With the aim to use advantages as good heat transfer and small hold up, the synthesis of a peroxycarboxylic ester, namely tert-Butyl peroxy-2-ethylhexanoate (TBPEH), was transformed into continuous mode using a tube reactor with inner dimension of 1 mm. An appraisal of the critical diameter of the tube was done in advance. The use of an ultrasonic device allowed for specific reaction parameters a nearly complete conversion of the educts. KW - Organic peroxide KW - Tubular reactor KW - Process safety KW - Continuous mode KW - Ultrasound PY - 2013 DO - https://doi.org/10.1016/j.cep.2013.03.019 SN - 0255-2701 VL - 70 SP - 217 EP - 221 PB - Elsevier CY - Lausanne AN - OPUS4-28937 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -