Copper and cobalt co-doped ferrites as effective agents for chemical looping CO2 splitting
Copper and cobalt co-doped ferrites as effective agents for chemical looping CO2 splitting
复制标题
铜钴共掺杂铁氧体作为化学链 CO2 分解的有效试剂
DOI：
10.1016/j.cej.2020.124150
复制
发表时间：
2020-05-01
影响因子：
15.1
通讯作者：
Xiao, Rui
中科院分区：
文献类型：
--
作者：
Qiu, Yu;Ma, Li;Xiao, Rui
通过在相对较低的温度（< 750℃）下操作化学环，可以避免氧载体材料的烧结。然而，低温对材料的氧化还原动力学有降解作用，从而限制了效率。在本工作中，我们报道了几种Co， Cu共掺杂尖晶石结构的铁氧体作为有效的氧化还原材料，在650℃的化学环方案中进行CO2热裂解，Cu0.2Co0.8Fe2O4的平均CO2裂解率高达144.9 mu mol.g（-1）。min(-1)， CO产量接近9.0 mmol。G（-1）在循环氧化还原操作中具有令人满意的稳定性。Cu、Co共掺杂提高了铁氧化物的还原性能，并使还原后的样品在CO2裂解阶段发生了可逆的相变。此外，Cu掺杂量的增加会导致活性杂质的形成不足，不利于CO2热分解。本工作的协同作用可为中温氧化还原材料的设计提供参考。
The sintering of oxygen carrier materials can be circumvented by operating chemical looping at relatively low temperatures ( < 750 degrees C). However, low temperature has a degrading effect on the redox kinetics of the materials and thereby limited efficiencies. In the current work, we report several Co, Cu co-doped spinel-structured ferrites as effective redox materials in the chemical looping scheme for CO2 thermo splitting at 650 degrees C. Cu0.2Co0.8Fe2O4 presents high average CO2 splitting rate of similar to 144.9 mu mol.g(-1).min(-1) and CO yield of similar to 9.0 mmol.g(-1) with satisfactory stability over cyclic redox operations. The improved performance can be attributed to the improved reduction of iron oxides by Cu, Co co-dopant, and the reversible phase change of the reduced sample in the CO2 splitting stage. Additionally, increasing Cu doping amount leads to the formation of insufficiently active impurities which is unfavorable for the CO2 thermo-splitting. The synergy in this work can be helpful for the design of the redox materials at moderate temperatures.