化工学报
化工學報
화공학보
CIESC Jorunal
2015年
10期
3931-3939
,共9页
绝热加速量热仪%反应动力学%过氧化苯甲酸叔丁酯%安全%爆炸%热失控反应
絕熱加速量熱儀%反應動力學%過氧化苯甲痠叔丁酯%安全%爆炸%熱失控反應
절열가속량열의%반응동역학%과양화분갑산숙정지%안전%폭작%열실공반응
accelerating rate calorimeter%reaction kinetics%tert-butyl peroxy benzoate%safety%explosion%thermal runaway reaction
过氧化苯甲酸叔丁酯(TBPB)对热不稳定,一旦在生产、储运过程中被H+或OH-污染,可能会对其热危险性产生较大影响。采用绝热加速量热仪在“加热-等待-搜索”和“等温”模式下研究了 H2SO4、NaOH 存在下TBPB的热分解反应行为,从热分解特性参数、反应动力学参数、最大反应速率达到时间TMR、自加速分解温度SADT四个方面定量表征了H+、OH-对TBPB热危险性的影响。采用“伪逆矩阵法”确定反应动力学参数,得到最不利条件下的热分解特征参数。采用Townsend算式,得到了考虑反应机理和反应物浓度的TMR推算式。基于Semenov理论,推算了0.5 L Dewar瓶和常用商业包装的SADT。结果表明:OH?污染物使TBPB发生两次放热,第一次放热释放能量不足以维持热失控反应,但加速TBPB老化变质,从而导致第二次放热反应动力学参数升高,热危险性减弱;H+污染物降低TBPB反应动力学参数,加剧热危险性;TMR和SADT推算结果表明H+污染物降低了TMR对应的报警温度,降低了包装容器的SADT。
過氧化苯甲痠叔丁酯(TBPB)對熱不穩定,一旦在生產、儲運過程中被H+或OH-汙染,可能會對其熱危險性產生較大影響。採用絕熱加速量熱儀在“加熱-等待-搜索”和“等溫”模式下研究瞭 H2SO4、NaOH 存在下TBPB的熱分解反應行為,從熱分解特性參數、反應動力學參數、最大反應速率達到時間TMR、自加速分解溫度SADT四箇方麵定量錶徵瞭H+、OH-對TBPB熱危險性的影響。採用“偽逆矩陣法”確定反應動力學參數,得到最不利條件下的熱分解特徵參數。採用Townsend算式,得到瞭攷慮反應機理和反應物濃度的TMR推算式。基于Semenov理論,推算瞭0.5 L Dewar瓶和常用商業包裝的SADT。結果錶明:OH?汙染物使TBPB髮生兩次放熱,第一次放熱釋放能量不足以維持熱失控反應,但加速TBPB老化變質,從而導緻第二次放熱反應動力學參數升高,熱危險性減弱;H+汙染物降低TBPB反應動力學參數,加劇熱危險性;TMR和SADT推算結果錶明H+汙染物降低瞭TMR對應的報警溫度,降低瞭包裝容器的SADT。
과양화분갑산숙정지(TBPB)대열불은정,일단재생산、저운과정중피H+혹OH-오염,가능회대기열위험성산생교대영향。채용절열가속량열의재“가열-등대-수색”화“등온”모식하연구료 H2SO4、NaOH 존재하TBPB적열분해반응행위,종열분해특성삼수、반응동역학삼수、최대반응속솔체도시간TMR、자가속분해온도SADT사개방면정량표정료H+、OH-대TBPB열위험성적영향。채용“위역구진법”학정반응동역학삼수,득도최불리조건하적열분해특정삼수。채용Townsend산식,득도료고필반응궤리화반응물농도적TMR추산식。기우Semenov이론,추산료0.5 L Dewar병화상용상업포장적SADT。결과표명:OH?오염물사TBPB발생량차방열,제일차방열석방능량불족이유지열실공반응,단가속TBPB노화변질,종이도치제이차방열반응동역학삼수승고,열위험성감약;H+오염물강저TBPB반응동역학삼수,가극열위험성;TMR화SADT추산결과표명H+오염물강저료TMR대응적보경온도,강저료포장용기적SADT。
Organic peroxide is widely used for initiating free radical polymerization in unsaturated polyester copolymerization reaction, and is thermally unstable in the presence of a single oxygen-oxygen bond, which easily leads to thermal runaway accident,i.e. explosion, when exposed to an external heat source. If any contaminant, such as H+ or OH-, is introduced during production, storage or transport, it may accelerate decomposition under an abnormal situation and result in deterioration. A liquid OP-tert-butyl peroxy benzoate (TBPB) was chosen to mix with NaOH and H2SO4 to examine H+ or OH- effects on its thermal hazard using an adiabatic accelerating rate calorimeter. The progresses in thermal decomposition of pure TBPB and mixtures with small amount of NaOH and H2SO4 are tracked using single “heat-wait-seek” operation mode and “isothermal age” plus “heat-wait-seek” mode, respectively. In order to characterize the effect of H+ and OH- on TBPB thermal hazard, the parameters of reaction kinetics and their corrected values with thermal inertia factor are determined from their characteristic parameters of thermal decomposition with pseudo inverse matrix method by least square method under the worst condition, and they are the characteristics of intrinsic thermal hazard of TBPB. The time to maximum heating rate (TMR) is predicted by Townsend equation involving reaction mechanism and reactant concentration. Based on the kinetic parameters and Semenov thermal explosion theory, the thermal hazard parameters, such as self accelerating decomposition temperature (SADT), CT, and ET, can be calculated, which are crucial for application in industry. A comparison of the mixtures to pure TBPB shows two exothermic peaks for mixture of TBPB and OH-. The first is at 60—70℃ and is characterized by very low heating rate and temperature rise, so that reaction heat is not sufficient to sustain the thermal runaway reaction, resulting in higher initial exothermic temperature and reaction kinetic parameters in the second exothermic stage,i.e. main exothermic stage. In contrast, without two peaks for the mixture of TBPB and H+, this mixture has lower reaction kinetic parameters, increasing reactivity and thermal hazard. The TMR and SADT data obtained by calculation indicate that the addition of H+ contaminant causes appropriately lower warning temperature. When 30 L high density polyethylene barrel packaging is adopted, the SADT of TBPB contaminated by H+falls from 65.9 to 62.6℃, indicating that strict temperature control measures are necessary.