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共沉淀法合成了Cu0.13Mg0 6Al0.27(OH)2(CO3)0.135·xH2O类水滑石物质 (CuHTlc) ,采用XRD、DTA TG、BET、TEM和27AlMASNMR技术对其热分解过程进行了表征。结果表明 ,在较低焙烧温度时 (低于300℃ ),氢氧根和层间水部分脱除 ,但水滑石仍保持其层状结构 ;500℃时 ,其层状结构被完全破坏 ,出现氧化镁晶相结构 ,随着焙烧温度的进一步升高 ,尖晶石晶相生成。500℃时的焙烧产物具有最大比表面 (193m2·g-1)。当温度高于500℃ ,焙烧产物组成可表示为Cu0.13Mg0.6Al0.27O0.135,CuHTlc的热分解过程可表示为 :Cu0.13Mg0.6Al0.27(OH)2(CO3)0.135·xH2O→Cu0.13Mg0.6Al0.27O0.135 +(1 +x)H2O +0.135CO2。
The pyrolytic process of Cu0.13Mg0 6Al0.27 (OH) 2 (CO3) 0.135 · xH2O was synthesized by coprecipitation method and characterized by XRD, DTA TG, BET, TEM and 27AlMASNMR. The results show that at lower calcination temperatures (below 300 ℃), the hydroxide and interlayer water partially remove, but the hydrotalcite still maintains its lamellar structure; at 500 ℃, the lamellar structure is completely destroyed and appears Magnesia crystal phase structure, with the further increase in calcination temperature, spinel crystal phase. The roasted product at 500 ° C had the largest specific surface (193 m2 · g-1). When the temperature is higher than 500 ℃, the calcined product composition can be expressed as Cu0.13Mg0.6Al0.27O0.135. The thermal decomposition process of CuHTlc can be expressed as: Cu0.13Mg0.6Al0.27 (OH) 2 (CO3) 0.135 · xH2O → Cu0.13Mg0.6Al0.27O0.135 + (1 + x) H2O + 0.135CO2.