CAJ | 학술논문

采用脉冲微反装置，在反应温度为550～650℃、低转化率（小于15％）条件下，研究了2，5﹣二甲基己烷在石英砂和ZRP分子筛上的热裂化和催化裂化反应，分析了甲烷的生成机理。结果表明：2，5﹣二甲基己烷热裂化反应的主要产物是甲烷、丙烯和异丁烯，在链传递阶段，甲基自由基夺氢可由3条反应路径生成甲烷，叔C—H 键对甲烷选择性的贡献大于90％；ZRP 分子筛的择形催化作用影响2，5﹣二甲基己烷催化裂化的转化率和产物分布，甲烷由质子化裂化反应生成；分析热裂化反应与质子化裂化反应对甲烷生成的影响可知，甲烷主要由热裂化反应生成，且随反应温度升高，热裂化反应对甲烷生成的贡献逐渐增大。
채용맥충미반장치，재반응온도위550～650℃、저전화솔（소우15％）조건하，연구료2，5﹣이갑기기완재석영사화ZRP분자사상적열열화화최화열화반응，분석료갑완적생성궤리。결과표명：2，5﹣이갑기기완열열화반응적주요산물시갑완、병희화이정희，재련전체계단，갑기자유기탈경가유3조반응로경생성갑완，숙C—H 건대갑완선택성적공헌대우90％；ZRP 분자사적택형최화작용영향2，5﹣이갑기기완최화열화적전화솔화산물분포，갑완유질자화열화반응생성；분석열열화반응여질자화열화반응대갑완생성적영향가지，갑완주요유열열화반응생성，차수반응온도승고，열열화반응대갑완생성적공헌축점증대。
The thermal and catalytic cracking reactions of 2 ,5﹣dimethylhexane were carried out at 550—650 ℃at low conversion (<15%)in a pulse micro﹣reactor over quartz and ZRP zeolite,respective﹣ly. Formation mechanism of methane was analyzed. The results show that methane,propylene and i﹣butylene are the primary products in thermal cracking. There are three reaction pathways that contrib﹣ute to the methane formation during chain propagation through the hydrogen extraction from C—H bond by methyl radical. The C—H bond attached to the tertiary carbon shows higher reactivity and ac﹣counts for more than 90% of methane selectivity during thermal cracking. The conversion and product distribution are clearly influenced by shape﹣selective catalysis and the methane is produced by protolytic cracking reaction during the catalytic cracking of 2 ,5﹣dimethylhexane over ZRP zeolite. The comparison of the contribution to methane between thermal and protolytic cracking pathways reveals that methane is mainly formed by thermal cracking,which gradually enhances along with the increase of reaction tem﹣perature.