Isothermal kinetic evaluation of methyl ethyl ketone peroxide mixed with acetone by TAM III tests

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<ul><li><p>Thermochimica Acta 507508 (2010) 4548</p><p>Contents lists available at ScienceDirect</p><p>Thermochimica Acta</p><p>journa l homepage: www.e lsev ier .c</p><p>Isother ketaceton</p><p>Jo-Minga Institute of Sa hnologb Graduate Sch echno</p><p>a r t i c l</p><p>Article history:Received 27 FeReceived in reAccepted 30 AAvailable onlin</p><p>Keywords:Methyl ethyl kRunaway reacAcetoneIsothermal kinThermal activi</p><p>O), thn, buwas tetontics oto deactor70, 8EKPOeviat</p><p> 2010 Elsevier B.V. All rights reserved.</p><p>1. Introduction</p><p>Methylamong the imerization,reason of Mof an accidecontrolled ffor this is serally an unexothermicother buildireactions hthe degreeinvolve reneers viewvery sensitistudy the bisothermalfrequency f</p><p>Novel einsight abo</p><p> CorresponE-mail add</p><p>unstable chemicals, such as organic peroxides. Based on these tech-</p><p>0040-6031/$ doi:10.1016/j.ethyl ketone peroxide (MEKPO), which is arguablymportant initiators and cross-linkers used during poly-has induced many accidents globally [1], that was theEKPO had been studied in this text. The developmentnt depends on progress in wrong dosing, temperature-ailure, pressure-controlled failure, andsoon. The reasonimple and straightforward: a runaway reaction is gen-expected process that once initiated may cause severereactions [2], and the release of heat can also affectngs or adjacent equipment. The evaluation of runawayas by necessity become more prevalent for lesseningof hazard, because in some cases such accidents may, explosion, toxic release, etc. From a chemical engi-point, MEKPO is treated as dangerous material that isve to a thermal source. In this study, we made effort toasic characteristic phenomena of runaway reactions bykinetic evaluation, such as activation energy (Ea) andactor (A).xperimental techniques are constantly bringing newut evaluating the kinetic parameters for thermally</p><p>ding author. Tel.: +886 4 2239 1647x6860; fax: +886 4 2239 9934.resses: jmtseng@ctust.edu.tw, 107108@ctust.edu.tw (J.-M. Tseng).</p><p>niques, fundamental concepts related to thermokinetics are beingtreated as crucial to precisely indicate the basic characteristicsfor runaway reactions [35]. Bunyan et al., apply thermal activ-ity monitor III (TAM III) to evaluate the hazard and identify thesafety parameters [6], Briggner et al., employ TAM to detect thephenomenon of crystallinity for lactose monohydrate [7], and thisisothermal method has also been extensively applied to evaluatehazardous materials [8,9]. The scope of this study is to describethe exothermic reaction and reaction model of MEKPO 31mass%and mixed with acetone 99mass% by the thermal activity moni-tor III (TAM III), which is likely to play an important role in thiseld, leading particularly to new methods for evaluating the run-away conditions during processing storage or transportation stage[10].</p><p>In this context,we focusedattentionon three specic isothermalconditions of 70, 80, and 90 C, for comparing the changes of reac-tions. All of the results demonstrated that MEKPO is a thermallydangerous material, due to its unstable group of OO and severeheat released, whereas the addition of acetone could decrease thedegree of hazard under mixing conditions. Reaction models, suchas nth-order or autocatalytic reactions, are critical for the evalua-tion process for more precisely realizing the reaction phenomena.In this way, thorough safety information can be provided for plantsto instruct their staff on how to protect the plant from an accidentduring runaway excursions.</p><p>see front matter 2010 Elsevier B.V. All rights reserved.tca.2010.04.028mal kinetic evaluation of methyl ethyle by TAM III tests</p><p>Tsenga,, Chi-Min Shub</p><p>fety and Disaster Prevention Technology, Central Taiwan University of Science and Tecool of Engineering Science and Technology, National Yunlin University of Science and T</p><p>e i n f o</p><p>bruary 2010vised form 29 April 2010pril 2010e 8 May 2010</p><p>etone peroxide (MEKPO)tions</p><p>etic evaluationty monitor III (TAM III)</p><p>a b s t r a c t</p><p>Methyl ethyl ketone peroxide (MEKPand cross-linker during polymerizatioTherefore, the purpose of this studyreactions ofMEKPO andmixedwith acis to determine the basic characterisaccident. Therefore, we endeavoredas activation energy (Ea), frequency funder three isothermal conditions of99mass%. The results showed that Mreaction. Moreover, acetone could allMEKPO.om/ locate / tca</p><p>one peroxide mixed with</p><p>y, 666, Buzih Rd., Beitun District, Taichung 40601, Taiwan, ROClogy, 123, University Rd., Sec. 3, Douliou, Yunlin 64002, Taiwan, ROC</p><p>e topic material, has been extensively applied as an initiatort it has also induced many severe accidents on a global scale.o deeply understanding the basic characteristics of runawaye. The innovative objective of an isothermal kinetic evaluationf reactive chemicals in order to prevent a serious runawaymonstrate the reaction model and kinetic parameters, such(A), and so on, by the thermal activity monitor III (TAM III)0, and 90 C, in terms of MEKPO 31mass% and with acetonecould liberate a great quantity of heat during exothermic</p><p>e the degree of exothermic runaway while being added with</p></li><li><p>46 J.-M. Tseng, C.-M. Shu / Thermochimica Acta 507508 (2010) 4548</p><p>Nomenclature</p><p>CdT/dt rate of heat accumulation or depletion, kJ/kgminf(c)gkkaPQRToTtUvdC/dtdQ/dtH</p><p>2. Isotherm</p><p>Eq. (1) inmal power</p><p>dC</p><p>dt= kf (C)</p><p>P = dCdt</p><p>H</p><p>P = Hkf (c</p><p>Here, dCdt</p><p>rate; f(c) isthermal powchange (J/g</p><p>Dynamicevaluatingequation sh</p><p>P = + dd</p><p>where isconstant ob</p><p>Eqs. (5)ature, wheraccumulatidepends onby a thermstability, wperature:</p><p>P = + C dd</p><p> = ka(T dQ</p><p>dt= ka(T</p><p>P = ka(TS </p><p>Eqs. (9)voltage (V),</p><p>Fig. 1. Structure of thermal activity monitor III [13].</p><p>ta [11]:</p><p>(T </p><p>U +</p><p>erim</p><p>epar</p><p>KPOsstoiluenwo metic</p><p>erma</p><p>IIIraturte teing inwereal ankinetic function depends on conversionsSeebeck coefcient, V/Kconstant of reaction rate, 1/sheat conductance, W/Kthermal power or heat production rate, W= J/sheat, Jgas constant, 8.314 J/molKtemperature of surrounding, Ktemperature of sample, Ktime, sheat transfer coefcient, kJ/minm2 Krate of change, mol/s, g/sreaction rate, 1/ssurrounding temperature, J/Kenthalpy change, J/gslope of the heat ow time curve, W= J/stime constant obtained from dynamic calibration, scalibration constant, W/V</p><p>al kinetic evaluation model</p><p>dicates the function of reaction rate, and then the ther-is obtained by Eqs. (2) and (3) [11]:</p><p>(1)</p><p>(2)</p><p>) (3)</p><p>1 is the reaction rate (1/s); k is the constant of reactionthe kinetic function depending on conversions; P is theer or heat production rate (W= J/s);H is the enthalpy</p><p>).correction is also a very critical procedure in precisely</p><p>the kinetic parameters applied in this study by Tiansown in Eq. (4) [12]:</p><p>t(4)</p><p>tion da</p><p> = ka</p><p>P = kag</p><p>3. Exp</p><p>3.1. Pr</p><p>MECo.,waas a dthese tthe kin</p><p>3.2. Th</p><p>TAMtempeAbsoluoperatationschemicthe slope of the heat ow time curve and is a timetained from dynamic calibration.(7) are the heat balance equation in terms of temper-e P is obtained by adding heat ow and rate of heaton or depletion; ka is the heat conductance (W/K); dQ/dtthe surrounding temperature, which can bemonitoredopile. Eq. (8) can be used to improve Eqs. (5)(7) forhere dQ/dt does not depend on the surrounding tem-</p><p>T</p><p>t(5)</p><p>To) (6)</p><p> To) + C dTdt</p><p>(7)</p><p>TR) + Cd(TS TR)</p><p>dt(8)</p><p>and (10) indicate the heat balance equation in terms ofand Eq. (10) is adopted to dynamically correct calibra-</p><p>III assistanteral oil witthe thermoTo) = kag</p><p>U T = Ug</p><p>+ To dTdt</p><p>= 1g</p><p>dU</p><p>dt(9)</p><p>C</p><p>g</p><p>dU</p><p>dt= ka</p><p>g</p><p>(V + C</p><p>ka</p><p>dU</p><p>dt</p><p>)= </p><p>(V + dU</p><p>dt</p><p>)(10)</p><p>ental setup</p><p>ation of MEKPO 31mass% and acetone 99mass%</p><p>31mass%, which was directly purchased from Aldrichred ina refrigerator at4 C.Acetone99mass%, employedt and also was stored in a refrigerator at 4 C. Afteraterials were mixed, we applied TAM III to evaluate</p><p>parameters based on the experimental data.</p><p>l activity monitor III (TAM III)</p><p>was used to investigate the runaway reaction underes of 70, 80, and 90 C, as shown in Figs. 1 and 2 [13].mperature could be adjusted to within 0.02K, whileisothermal mode, the bath mean temperature uctu-within 105 K. A maximum scanning rate is 2K/h ford physical equilibrium. We used the software of TAMto control the thermostat. The thermostat liquid ismin-h a total volume of 22 L, and the temperature range ofstat is 15150 C when mineral oil is employed [13].Fig. 2. TAM III thermostat principle [13].</p></li><li><p>J.-M. Tseng, C.-M. Shu / Thermochimica Acta 507508 (2010) 4548 47</p><p>Table 1Experimental data by TAM III tests for MEKPO 31mass% and with acetone 99mass%.</p><p>Sample Temperature (C) Sample mass (mg) Cell Reaction time (day) Hd (J/g)</p><p>MEKPO 31mass%70 101.29 Glass ampoule 16.2 1002.1780 102.34 Glass ampoule 9.8 1206.1890 104.18 Glass ampoule 3.7 1135.92</p><p>MEKPO 31mass%+acetone99mass%</p><p>70 MEKPO (102.25) + acetone (13.22) Glass ampoule 16.2 810.4280 MEKPO (105.18) + acetone (13.95) Glass ampoule 9.8 976.4190 MEKPO (102.59) + acetone (15.70) Glass ampoule 3.7 937.02</p><p>Table 2Time tomaximumrate at three temperatures forMEKPO31mass% andwith acetone99mass%.</p><p>Sample Temperature (C) TMR (day)</p><p>MEKPO31mass%</p><p>70 6.780 3.390 0.9</p><p>MEKPO 31mass%+acetone99mass%</p><p>70 8.180 3.690 1.0</p><p>Fig. 3. Heat poand with aceto</p><p>4. Results</p><p>Experimand Figs. 3conditionsforMEKPO c</p><p>Figs. 331mass%anconditions o</p><p>Fig. 4. Heat poand with aceto</p><p>eat power vs. time for the thermal decomposition of 31mass%MEKPOaloneacetone 99mass% at 90 C.Fig. 5. Hand withwer vs. time for the thermal decomposition of 31mass%MEKPOalongne 99mass% at 70 C.</p><p>and discussion</p><p>ental results by TAM III tests are shown inTables 1 and27. All of the results detected under three isothermal</p><p>of 70, 80, and 90 C indicated that the heat of reactionould be signicantly lessenedwith addition of acetone.</p><p>5 depict the result of the measurements on MEKPOdmixedwith acetone99mass%under three isothermalf 70, 80, and 90 C. From these peaks it can be observed</p><p>wer vs. time for the thermal decomposition of 31mass%MEKPOalongne 99mass% at 80 C.</p><p>Fig. 6. Tempeat 70, 80, and</p><p>that the spralone andadded intolessenedsigunder three</p><p>Fig. 7. Tempewith 99mass%rature vs. normalized heat ow for evaluating Ea of 31mass% MEKPO90 C (Ea =82.86.0 kJ/mol).</p><p>ead of the results between both conditions of MEKPOwith acetone is very clear. While acetone was beingthe glass ampoule with MEKPO, the heat of reactionnicantly from10001200 to810976 J/g, respectively,different temperatures. When these two materials are</p><p>rature vs. normalized heat ow for evaluating Ea of 31mass% MEKPOacetone at 70, 80, and 90 C (Ea =84.96.2 kJ/mol).</p></li><li><p>48 J.-M. Tseng, C.-M. Shu / Thermochimica Acta 507508 (2010) 4548</p><p>beingmixed, free radicals produced byMEKPO can be transformedto more stable enol radicals [14]. Figs. 6 and 7 show the evalua-tion results of activation energy for MEKPO and with acetone byemploying the Arrhenius equation, as shown in Eq. (11):</p><p>ki(T) = A exp(</p><p> EaRT</p><p>)(11)</p><p>where A, Ea, and R represent, respectively, the frequency fac-tor, the activation energy of the stage, and the gas constant(R=8.314 J/molK). The Ea was about 82.86.0 kJ/mol for pureMEKPO, and Ea =84.96.2 kJ/mol for MEKPO mixed with acetone.Both results demonstrate that the exothermic reaction tended tolessen when acetone was added, and the MEKPO is a thermallyunstable material because of the weak OO bond [15]. In terms ofthe time to maximum rate (TMR), which could be applied to eval-uate the degree of hazard during storage or transportation, TMR isalsooneof the safetyparameters [14,16]prevailinglyused inplants.While acetone was added into a glass ampoule with MEKPO, theTMR was increased about 1.4, 0.3, and 0.1 days under isothermalconditions of 70, 80, and 90 C, respectively. Therefore, the degreeof hazard was lessened under mixture conditions. By this point,we could signicantly realize a tendency that the TMR had clearlyincreased with lower isothermal temperature.</p><p>Note that it is alsopossible toobserve runaway reactionsunder alower isothermal temperature, as per the extension of the reactiontime. It can also be seen that TAM III is an excellent instrument forthe study of discussing runway reactions. For storage and trans-portation measurements, an isothermal calorimeter, such as theTAM III has been demonstrated to be a better instrument than anon-isothermal calorimeter.</p><p>5. Conclusions</p><p>We employed TAM III to evaluate the basic characteristics ofMEKPO 31mass% and with acetone 99mass%, in terms of runaway</p><p>reactions. TMR is a quick and effective safety parameter to pre-cisely evaluate the degree of hazard under isothermal conditions.As revealed in this study, acetone alleviated theheat of reaction andalso increased the TMRwhilemixedwith pureMEKPO. It could alsobe treated as the degree of hazard was decreased. Therefore, all ofthe safety information generated by this study will be provided tothe relevant plants for mitigating the loss of property and humanlife.</p><p>Acknowledgments</p><p>We are indebted to Dr. Jai P. Gupta of the Department of Chem-ical Engineering, Indian Institute of Technology Kanpur, India, forhis valuable technical assistance.</p><p>References</p><p>[1] J.M. Tseng, C.M. Shu, Y.C. Yu, Korean J. Chem. Eng. 22 (2005) 797802.[2] D. Swern, Organic Peroxides, John Wiley &amp; Sons, Inc., New York, USA, 1970.[3] A.A. Kossoy, E. Koludarova, J. Loss Prev. Process Ind. 8 (1995) 229235.[4] P. Ptacek, D. Kubatova, J. Havlica, J. Brandstetr, F. Soukal, T. Opravil, Ther-</p><p>mochim. Acta 501 (2010) 2429.[5] K. Muraleedharan, M.P. Kannan, T. Gangadevi, Thermochim. Acta 502 (2010)</p><p>2429.[6] P.F. Bunyan, T.T. Grifths, V.J. Norris, Thermochim. Acta 401 (2003) 1725.[7] L.E. Briggner, G. Buckton, K. Bystrom, P. Darcy, Int. J. Pharm. 105 (1994)</p><p>125135.[8] H.D. Ferguson, D.I. Townsend, T.C. Hofelich, P.M. Russell, J. Hazard. Mater. 37</p><p>(1994) 285302.[9] L.E. Paulsson, Thermochim. Acta 214 (1993) 141144.</p><p>[10] J.C. Jones, Combus. Flame 124 (2001) 334336.[11] Calorimetric Principles, TAM III Training Course, Taiwan, ROC (2008).[12] Calibration, TAM III Training Course, Taiwan, ROC (2007).[13] Product Information, TAM III Thermostat. Available at:</p><p>www.thermometric.com (2008).[14] J.M. Tseng, Y.Y. Chang, T.S. Su, C.M. Shu, J. Hazard. Mater. 142 (2007) 765770.[15] J.M. Tseng, R.H. Chang, J.J. Horng, M.K. Chang, C.M. Shu, J. Therm. Anal. Calorim.</p><p>85 (2006) 189194.[16] D.I. Townsend, J.C. Tou, Thermochim. Acta 37 (1980) 130.</p><p>Isothermal kinetic evaluation of methyl ethyl ketone peroxide mixed with acetone by TAM III testsIntroductionIsothermal kinetic evaluation modelExperimental setupPreparation of MEKPO 31mass% and acetone 99mass%Thermal activity monitor III (TAM III)</p><p>Results and discussionConclusionsAcknowledgmentsReferences</p></li></ul>

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