基于改性沥青粘结剂的TiB_2-C复合阴极抗碱金属渗透性能  

Penetration resistance performance to alkali metal of TiB_2-C composite cathode based on modified pitch binder

作　　者：方钊[1] 刘佰龙[1] 洪涛[1] 李林波[1] 朱军[1] 

机构地区：[1]西安建筑科技大学冶金工程学院,陕西西安710055

出　　处：《轻金属》2012年第6期36-39,46,共5页Light Metals

摘　　要：以树脂(沥青、呋喃、酚醛)改性沥青为粘结剂制备了铝电解用TiB2-C复合阴极,考察其在[K3AlF6/Na3AlF6]-AlF3-Al2O3熔体中的低温电解膨胀性能;采用TGA对改性沥青的结焦过程动力学进行研究。结果表明,与原始沥青基TiB2-C复合阴极相比,改性沥青基TiB2-C复合阴极的低温电解膨胀率均有所降低。树脂(呋喃、酚醛、环氧)改性沥青基TiB2-C复合阴极的电解膨胀率分别为:1.61%、1.62%、1.68%,之间相差不大,与原始沥青基TiB2-C复合阴极相比,最大降幅达到了13.77%;粘结剂热解过程的表观活化能大小与复合阴极的电解膨胀率有关,活化能越高,其所对应复合阴极的电解膨胀率越低。呋喃、酚醛、环氧改性沥青粘结剂热解过程的表现活化能分别为:66.25kJ/mol,57.07kJ/mol和63.24kJ/mol,而未改性沥青热解过程的表观活化能仅为47.21kJ/mol,这正好解释了前述高温电解质熔体中阴极电解膨胀率的测试结果。TiB2 - C composite cathodes were prepared using pitch modified by furan, phenolic - aldehyde and epoxy as binder, and their electrolysis expan- sion in [ K3A1F6/Na3A1F6 ] - AIF3 - Al2O3 melts was tested. Dynamics relate to pyrolytic process was also studied by TGA. The results suggest that modi- fied pitch based composite all exhibit lower electrolysis expansion which are 1.61% （ furan）, 1.62% （ phenolic - aldehyde） and 1.68% （epoxy） respec- tively without significant difference. But compared with the original pitch based composite ,The maximum depressed amplitude can reach 13.77%. Electrol- ysis expansion of composite cathodes is related to apparent activation energy （AAE） concerning pyrolysis process of pitch. The higher the AAE,the lower the electrolysis expansion. The AAE of pitch modified by furan, phenolic -aldehyde, and epoxy are 66. 25k J/tool ,57.07kJ/mol and 63.24kJ/mol, while the AAE of unmodified pitch is only 47.21 kJ/mol. The values of them appropriately illuminate the test result of electrolysis expansion mentioned above.

关 键 词：改性沥青 活化能 电解膨胀 铝电解 

分 类 号：TF821[冶金工程—有色金属冶金]