The effect of surfacefactant(polyvinylalcohol,PVA) and lanthanum on the property of alumina was studied by XRD,XPS,TEM and surface analysis techniques.The results showed that addition of proper amount of PVA and lanth...The effect of surfacefactant(polyvinylalcohol,PVA) and lanthanum on the property of alumina was studied by XRD,XPS,TEM and surface analysis techniques.The results showed that addition of proper amount of PVA and lanthanum can prevent alumina crystal from growing at high temperature and inhibit alumina from transforming to α phase and improve its pore structure.PVA can also make lanthanum less rich at the surface of samples,so alumian can keep high surface area after calcination at high temperature,then its thermal stability was improved.When W(La)∶W(Al)=0.052∶1 and W(PVA)∶W(alumina)=0.4∶1,the alumina can maintain surface area of 102.7m 2g -1 after calcination at 1100℃ for 32h.展开更多
A high temperature resistant alumina with high specific surface area was prepared by sol-gel method. XRD,TEM,XPS and surface analysis method were used to study the effect of dopant lanthanum on the alumina.The results...A high temperature resistant alumina with high specific surface area was prepared by sol-gel method. XRD,TEM,XPS and surface analysis method were used to study the effect of dopant lanthanum on the alumina.The results showed that lanthanum ion could suppress alumina transition to α-phase and then inhibit alumina from sintering and the thermal stability of the Al 2O 3 was improved. Different ratios of La/Al had different effects on the specific surface area of Al 2O 3.The Al 2O 3 containing 1.0 mol/% lanthanum has a BET specific surface area of 71.8 m 2/g after calcination for 32 hours at 1*#100℃, whereas the undoped Al 2O 3 only had a BET specific surface area of 10 m 2/g under similar conditions.展开更多
文摘The effect of surfacefactant(polyvinylalcohol,PVA) and lanthanum on the property of alumina was studied by XRD,XPS,TEM and surface analysis techniques.The results showed that addition of proper amount of PVA and lanthanum can prevent alumina crystal from growing at high temperature and inhibit alumina from transforming to α phase and improve its pore structure.PVA can also make lanthanum less rich at the surface of samples,so alumian can keep high surface area after calcination at high temperature,then its thermal stability was improved.When W(La)∶W(Al)=0.052∶1 and W(PVA)∶W(alumina)=0.4∶1,the alumina can maintain surface area of 102.7m 2g -1 after calcination at 1100℃ for 32h.
文摘A high temperature resistant alumina with high specific surface area was prepared by sol-gel method. XRD,TEM,XPS and surface analysis method were used to study the effect of dopant lanthanum on the alumina.The results showed that lanthanum ion could suppress alumina transition to α-phase and then inhibit alumina from sintering and the thermal stability of the Al 2O 3 was improved. Different ratios of La/Al had different effects on the specific surface area of Al 2O 3.The Al 2O 3 containing 1.0 mol/% lanthanum has a BET specific surface area of 71.8 m 2/g after calcination for 32 hours at 1*#100℃, whereas the undoped Al 2O 3 only had a BET specific surface area of 10 m 2/g under similar conditions.
