高氯酸羥胺熱分解動(dòng)力學(xué)

第51卷第1期化工報Vol. 51 No l2000年2月Journal of Chemical Industry and Engineering( ChinaFebruary 2000研究簡(jiǎn)報A高氯酸羥胺熱分解動(dòng)力學(xué)米鎮濤常志華張香文邱立勤王亞權天津大學(xué)化工學(xué)院,天津300072)關(guān)鍵詞高氯酸羥胺分解動(dòng)力學(xué)熱分析圖分類(lèi)號O643.122實(shí)驗結果高氯酸羥胺(HAP)是一種用于推進(jìn)技術(shù)領(lǐng)21熱失重分析域的新型高能氧化劑,在高性能推進(jìn)系統中具有極4個(gè)體系的熱重曲線(xiàn)如圖1所示.由于HAP為重要的價(jià)值1-31吸濕,其熱重曲線(xiàn)在100℃以下部分主要與其脫水用熱分析技術(shù)研究含能物質(zhì)的熱分解,已有大有關(guān),圖2為純HAP熱分解的TG-DIG曲線(xiàn)圖量報道45.而對于HAP的熱分解的報道較少6-81,采用熱分析技術(shù)研究HAP的分解動(dòng)力學(xué)目前還沒(méi)有文獻報道.本文用熱解重量分析法(TG)和差示熱分析(DTA)對HAP的熱分解進(jìn)了研究.根據HAP合成及貯運中可能引入的雜EE質(zhì),研究了NH4+、H、Fe3+對HAP熱分解行為的影響1實(shí)驗部分3003504004505005506001.1高氯酸羥胺固體樣品的制備Fig 1 TG curves of HAP samples將HAP水溶液及含有添加物的HAP水溶液減1-HAP+Fe+; 2-HAP: 3-HAP+ NHA;4-HAP+H壓下蒸發(fā)(<80℃),濃縮后結晶,制得如下HAP固體樣品:純HAP固體結晶;含高氯酸銨α4.0%的HAP固體;含高氯酸α=3.0%的HAP固體;含三氯化鐵(Clˉ對HAP熱安定性無(wú)影響j1ae=0.29%的HAP固體1.2熱分析實(shí)驗IG和DTA分別在日本島津公司制造的TGA50型熱重分析儀和DTA-50型差熱分析儀上進(jìn)行由于HAP吸濕,通過(guò)試驗確定在100℃停留30300350400450500550600min作為脫水條件,在此條件下HAP不發(fā)生分解TG實(shí)驗是在20 mt min的氮氛下以10℃.min1中國煤化工升溫至100℃,停留30min,再以8℃min1升溫of neat hapCNMHG至300℃結束.DTA實(shí)驗的氮氣流速為50m其他條件同熱重分析從圖1可以看出,與純HAP的分解相比,含高氯酸銨的HAP以及含高氯酸的HAP的分解被延遲,而含氯化鐵的HAP的分解則提前了.表1給134化工報2000年2月出了4種樣品的分解溫度,從表中數據可以看到,使得總放熱量降低較多.含銨HAP和含酸HAP由氯化鐵對HAP分解的促進(jìn)作用很明顯,它使HAP于含有雜質(zhì),因此它們的焓差絕對值要低于純的分解峰溫提前了大約65K,分解溫度區間ΔTHAP的焓差絕對值.由于在該條件下高氯酸銨還也比其余樣品小10K左右,而且其失重曲線(xiàn)很陡,沒(méi)有發(fā)生分解,故含銨HAP的焓差絕對值比含酸說(shuō)明分解速度非?？?銨和酸則對HAP的分解起HAP的焓差絕對值低了延遲作用,其分解溫度區間△T與純HAP的相近.含銨HAP的分解峰溫與純HAP的相比延后3HAP熱分解反應動(dòng)力學(xué)20K左右,含酸HAP上述特征值延后30K左右.3.1模型方程的建立這可能是由于銨和酸的存在稀釋了HAP的濃度,在熱重分析中,物質(zhì)的熱分解速率用下式表示從而降低了HAP的起始分解速度,而使得分解峰=k T)/( a)(1)溫后移.由于純HAP的分解是HAP先解離成羥胺和高氯酸,再進(jìn)一步發(fā)生羥胺和高氯酸的氧化分式中a為分解分數,即失重率,其定義式為解,高氯酸的存在使第1步解離反應變得困難,降低了HAP起始分解速度,因此含高氯酸HAP的分式中m0為樣品的起始質(zhì)量,m為樣品在T℃時(shí)解峰溫比含銨HAP的相應值又延后10K左右.此的質(zhì)量,m;為樣品的最終質(zhì)量.式(1)中,k外,從平均失重速率數據中也可得出上述結論。含(7)為T(mén)℃時(shí)的速率常數,根據 Arrhenius方程有鐵HAP的失重速率比純HAP快30%,說(shuō)明鐵對k(t)=AeHAP的分解起加速作用;含銨HAP的失重速率與式(1)中的函數f(a)參照質(zhì)量作用定律,采用純HAP相近,說(shuō)明銨只是延遲了HAP的分解,當冪函數形式,在此可寫(xiě)成f(a)=(1-ay,分解發(fā)生后,銨基本上對分解無(wú)影響;含酸HAP得到的失重速率比純HAP略低,表明酸對HAP的分解da= Ae E/RT((4)有微弱的阻滯作用在恒定的程序升溫速率下B=dT/dt,則(5)Table 1 TG data of samples△a(△t)從上式可求出高氯酸羥胺分解動(dòng)力學(xué)方程式Ta/KT/K(a#)r(1-a)(6)HAP12.95448.09~501.124900.150HAP+NH411.12468,11-521.31510.420.149采用多元線(xiàn)性回歸法擬合式(6),便可求出動(dòng)力學(xué)HAP +H5.24477.58-532.37519.910參數HAP+Fe315.47390.48-431.17425.480.195實(shí)驗中取得的失重速率數據是以dm/dt表示2.2差熱分析的,需要轉換為da/dt.式(2)兩邊同時(shí)對t微對HAP樣品的差熱分析結果與熱重分析的結分,得到dm/dt果對應性較好,其規律與熱重分析類(lèi)似.樣品的差(7)熱分析數據見(jiàn)表2.在表2的樣品熱效應數據中,3.2動(dòng)力學(xué)參數的求解含鐵HAP的焓差絕對值最低,這可能是由于它的表3表6分別列出了純HAP,HAP分解溫度較低分解的初級產(chǎn)物沒(méi)有進(jìn)一步分解,NHCO, HAP-HCIO2和HAP-FeCl3體系的熱分解失重數據Table 2 DTA data of samples中國煤化工方程(6),求得了相△H/k卜g應4CNMHG型參數,歸納于表7HAP498,13699,91其回歸的偏差平方和Q<0.152,標準偏差S0.98(含Fe物系偏差稍大)HAP+H'比較4個(gè)體系的動(dòng)力學(xué)參數發(fā)現,其活化能EHAP+詬方數據18.3432,90477,81和反應級數n的順序為第51卷第1期米鎮濤等:高氯酸羥受熱分解動(dòng)力學(xué)135Table 3 Data for neat HAP thermal decomposition by TG and DTGT/Kda( dtda(dt)469.420.085100.07294483.790.3.3060.2528490.530.64590.5.319472.560.11640,09492485,530,38580,31705343450.14890.11779486.950.44500.3858147.410.18488.240,5090,4535493.5179330,498323011739489.650.58330.50889133938482,080.28080.2098Table 4 Data for thermal decomposition of HAP with NH, CIO by TG and DTGda( dtT/Kda( dzT/KT/Ka/n488.580.086270.081766500.350.28750.2179508.570.61320.4365491.160.11581027390.347309.660.67544465493.560.14990.12568504.460.41710.317213511.260.75730.42734496.030.19281534506.220.49150.3736513.190.8323498.090.23330.I805507.380.5495515.140.93780.2016Table 5 Data for thermal decomposition of HAP with HCIO by TG and DTGda( dt/1、da(dtda(dt)T/KT/K01.000.094640.08449513.230.36090.2965519,910.65520.392503.950.13150.12227514.930.42890.3326521.020.71510.3856506.560.17540.1636516.590,49660.3605767019.180.23880.21439517.630.54520.37630.8385.318511.680.31020.2651518.750.59430.3870525,710.89982452Table 6 Data for thermal decomposition of HaP with FeC13 by TG and DTOda( dtda( dtda( dtT/KT/K390.480.0079940,008560414,900.091260,112420,480.26860.666414.660.012730.01189416.650.10990.2209421.120.31517217398.720,019740,01670417,590,12320,3065421,6936100,7630403.060.030630.02342419.100.17960.5002422.310.40810.7966407,470.045350,03474419,960,22670,5990422,830.45040.8162411.610.065510.05285了純HAP及含有添加物的HAP體系的熱分解動(dòng)力Table 7 parameters of kinetics equations學(xué)方程(2)TG和DTA實(shí)驗結果表明3價(jià)鐵對HAPHAP0.3783.37×102的分解有促進(jìn)效果而銨離子和酸對HAP的分解無(wú)HAP+H0.9246.14×102促進(jìn)作用,銨相當于惰性組分酸則對HAP的分解HAP+ F4.07×1020中國煤化工HAP+ FeCl3< HAP< HAP+ NH CIO4 HAP+ HCIOTHaCNMHG明這也反映了4個(gè)體系的熱安定性順序A—指前因子min-14結論E—活化能↓mol1H——焓差k1)用方揖G研究了HAP熱穩定性得到k—速率常數min化工報2000年2月m—物質(zhì)質(zhì)量mgplosives and Propellants(火炸藥學(xué)報)9982I(2)36-38-反應級數Mueller K F Ciesla M J. US 5223057. 1993R——通用氣體常數mol-tK3 Biddle R A Sutton E s US 4527389, 1985T——溫度K4 Tian Linxiang(田林祥) Explosives and Propellants(火炸藥)1996,194)43-45w—質(zhì)量分數5 Mishra S C, Pant J, Pant G C Dutta P K, Durgapal U C Propa—失量率nts Explosives Pyrotechnics 995 20 91-956 Goshgarian BB AD 692492. 196B——升溫速率℃min17 Cordes H F, Smith SR. J. Inorg. Nucl. Chem., 1970 32(4)下角標1135-1139d—分解f—最終Sinica of USSR Series of Chemistry ,1980171463--1469p——峰值9 Chang Zhihua(常志華). Optimization of Technological Parameter0——起始[ dissertation I學(xué)位論文). Tianjin, Tianjin University1998References1 Mi Zhentad米鎮濤) Qiu liqin邱立勤). Chinese Journal of ExKINETICS OF THERMAL DECOMPOSITION OFIYDROXYLAMINE PERCHLORATEMi Zhentao Chang Zhihua, Zhang Xiangwen, Qiu Liqin and Wang YaquanSchool of Chemical Engineering and Technology, Tianjin University Tianjin 300072)Abstract Hydroxylamine perchlorate( HaP )is a new energetic oxidizer. The thermal decomposition of pureHAP and the effects of additives on thermal decomposition of HaP were studied by using TG and DTA in nitrogen atmosphere. The additives are 4.0%NH4CIO4,3.0%HCIO4 and 0. 29% FeCl respectively. The TGcurves of the above four systems were determined. The experimental results indcate that FeCl, has a promotingeffect on the decomposition of hap but NH CIO4 and HClO4 have no such effect on the decomposition of HAPNH4CIO4 acts as an inert substance and HCIO4 has a weak retarding effect on the decomposition of haP, busing non-isothermal TG-DTG the thermal decomposition kinetic equations of the four systems were obtainedThrough comparing the kinetic parameters of the four systems ,the order of decomposition activation energy (eand reaction order( n )were foundHAP +0. 29% FeCl3< HAP< HAP+ 4.0%NH, CIO4 HAP +3.0%HCIOThis also indicates the order of thermal stability of the four systems. The thermal decomposition data of dtashow that the decomposition heat of HAP is-69991 kf g and the decomposition peak temperature of HAPis 498 13K. With the decomposition peak temperature of HAP FeCl3to 432 90K, the ones of hap tNH CIO4 and HAP+ HCIO4 increase to 520.03 K and 532.90 K respectivelyKeywords hydroxylamine perchlorate decomposition kinetics中國煤化工CNMHGTo whom correspondence should be addressed