CaO和MnO2双修饰的γ-Al2O3催化再生乙基蒽醌工作液

Catalytic Regeneration of Ethylanthraquinone Working Solution by Ca O and MnO2 Double Modified γ-Al2O3 Catalyst

针对蒽醌法生产工艺中广泛使用的γ-Al2O3对蒽醌降解物再生效率低的不足,以γ-Al2O3为载体,采用浸渍法制备了不同CaO负载量的CaOγ-Al2O3催化剂,考察了CaO含量对乙基蒽醌工作液再生的影响,筛选出最佳的CaO负载量为3.0%(3.0CaO/γ-Al2O3)。在此基础上,进一步制备了CaO和MnO_2双修饰的催化剂,考察了MnO2负载量对3.0CaOγ-Al2O3催化乙基蒽醌工作液再生的影响,表明Mn O2负载量为0.5%的催化剂(3.0CaO0.5MnO2/γ-Al2O3)性能较好。采用X射线荧光光谱、氮气低温物理吸附和X射线粉末衍射等表征手段对三个代表性催化剂的物理化学性质进行了研究。结果表明,与γ-Al2O3和3.0CaO/γ-Al2O3相比,双修饰的3.0CaO0.5MnO2/γ-Al2O3催化剂不仅明显促进了工作液中四氢-2-乙基羟基蒽酮(OXOH4e AQ)和四氢-2-乙基蒽醌环氧化物(EPOXH4e AQ)的再生,而且加速了四氢-2-乙基蒽醌(H4e AQ)向2-乙基蒽醌(eAQ)的转化。经优化得到的3.0CaO0.5MnO2/γ-Al2O3具有一定的工业应用前景。

Aiming at the defects of low efficiency of γ-Al2O3 for regeneration of degradation products in anthraquinone process,γ-Al2O3-supported CaO/γ-Al2O3 catalysts with different CaO loadings were prepared via impregnation method. The effects of CaO loading on regeneration of the ethylanthraquinone working solution were investigated, and the optimized CaO loading was selected to be 3.0%(the catalyst is denoted as 3.0CaO/γ-Al2O3). On the basis of this, the CaO and MnO2 double modification catalysts were further prepared and the effects of MnO2 loading on 3.0CaO/γ-Al2O3 for regeneration of the ethylanthraquinone working solution were investigated, and the catalyst (3.0CaO0.5MnO2/γ-Al2O3) with a MnO2 loading of 0.5% had better performance. The physicochemical properties of three representative catalysts were characterized by X-ray fluorescence spectroscopy, N2 low temperature physisorption, and X-ray power diffraction. The results showed that compared with the unmodified γ-Al2O3 and 3.0CaO/γ-Al2O3, the double modified 3.0CaO0.5MnO2/γ-Al2O3 not only significantly promoted the regeneration of tetrahydro-2-ethyl-hydroxylanthrone( OXOH4eAQ) and 2-ethyl-tetrahydroanthraquinone epoxide(EPOXH4eAQ) in the working solution, but also accelerated the conversion of tetrahydro-2-ethylanthraquinone (H4eAQ) to 2-ethylanthraquinone. Therefore, the optimized 3.0CaO0.5MnO2/γ-Al2O3 catalyst has certain industrial application prospects.