화학공학소재연구정보센터
Separation and Purification Technology, Vol.209, 734-740, 2019
Continuous removal of Cr(VI) and Orange II over a novel Fe-0-NaA zeolite membrane catalyst
A novel Fe-0-NaA zeolite membrane catalyst was prepared for continuous removal of Cr(VI) and Orange II (OII) in a fixed bed reactor. Firstly, the NaA zeolite membrane on the paper-like sintered stainless steel fibers support was prepared by wet lay-up papermaking technique and secondary growth method. Then, Fe-0-NaA zeolite membrane catalyst was synthesized by traditional liquid-phase technique and characterized by using scanning electron microscopy (SEM) and X-ray diffraction (XRD). Finally, catalytic activity of Fe-0-NaA zeolite membrane catalysts was studied by investigating the breakthrough time of Cr(VI) and conversion of Oil as well as the iron leaching concentration in the effluent based on the reduction reaction and catalytic wet peroxide oxidation (CWPO) processes in a fixed bed reactor. The results showed that nanoscale Fe-0 particles were uniformly loaded on the surface of the NaA zeolite membrane. An acidic environment was more favorable to the reduction of Cr (VI) and the breakthrough time reached 300 min for 4.7% breakthrough at pH 2. Both Yoon-Nelson and Bed Depth Service Time (BDST) models were found to agree well with the experimental results of Cr(VI) removal. The catalyst for CWPO of Oil achieved the highest activity (OII conversion > 97%, COD removal ratio about 86.0%, respectively) after continuously ran for 240 min. Meanwhile, low iron leaching concentration (< 3.5 mg/L) was detected in the treated effluent.