文档介绍：华中科技大学
硕士学位论文
CuO/γ-Al<,2>O<,3>催化剂脱硝吸附性能研究
姓名:王乐乐
申请学位级别:硕士
专业:热能工程
指导教师:向军;孙路石
20090501
华中科技大学硕士学位论文
摘要
煤燃烧过程中产生大量的NOX对环境造成严重危害。CuO/γ-Al2O3催化剂可以
有效脱除电厂烟气中的氮氧化物。目前,国内外对该催化剂的研究多以工艺脱除效果
和流程化学为重点,而对脱硝过程中催化剂表面NH3、NO吸附性能研究不足。因此,
有必要研究CuO/γ-Al2O3催化过程中吸附作用的微观机理,分析其对脱硝效率的影响,
为催化剂的进一步改善提供理论依据。
高效催化剂的制备,是整个研究工作和实验进行的基础。因此,论文首先介绍溶
胶凝胶法制备CuO/γ-Al2O3催化剂的过程,并研究制得催化剂的脱硝效果;之后,通过
催化剂表面脱附和暂态实验,探讨NH3和NO在脱硝反应中的化学吸附性能;最后,用
量子化学方法从理论上研究NH3和NO等气体分子在催化剂表面的吸附行为,并与前面
实验得出结论进行综合,解释催化过程中吸附作用对脱硝性能的影响。
论文研究表明:溶胶凝胶法制备的CuO/γ-Al2O3催化剂拥有优良的结构特征,因此
具有较好的催化脱硝活性;NH3和NO在催化剂上都存在明显的吸附现象,其吸附有利
于脱硝反应的发生,O2的吸附可以有效地补充反应过程中催化剂消耗的晶格氧,较长
时间内保持催化剂的活性;量子化学计算得到催化剂吸附NO需要克服较大的能垒,
吸附作用较难发生,NH3的吸附则容易进行,形成的吸附键具有一定的强度,从而保
证反应中活性组分CuO上充足的NH3吸附量。吸附作用引起的分子几何构型变化和电
荷的转移及重新分配,有利于反应物分子内部价键的断裂和产物的形成。

关键词:脱硝 CuO/γ-Al2O3催化剂吸附量子化学电荷转移
I
华中科技大学硕士学位论文
Abstract
NOX from bustion process results in serious harm to the environment. The
CuO/γ-Al2O3 catalysts can remove nitrogen oxides from flue gas effectively. At present, the
study on this catalysts is main about the removal effect of technology and chemical
processes,but less on NH3 and NO adsorption properties on catalysts surface. So, it was
necessary to study on the adsorption mechanism of catalysts and analyze the impact to
denitrification efficiency, which was helpful to the improvement of catalyst performance.
Preparing a highly efficient catalytic adsorbent is at the root of this study. Above all,
the process of preparing CuO/γ-Al2O3 catalysts by the sol-gel method was introduced. And
then, the denitrification efficiency of CuO/γ-Al2O3 catalysts was defined in a fixed-bed
reactor. To obtain more information about the adsorption behaviors of NH3 and NO in this
system, desorption experiments and transient behaviors had been carried out. Eventually, the
chemical adsorption properties of NH3 and NO molecules on CuO/γ-Al2O3 catalysts surface
had been investigated by using a quantum chemistry calculation, the res