摘要
通过过饱和浸渍法制备TiO_2/Ni-ZSM-5光催化剂,并利用XRD、N_2吸附-脱附、UV-Vis、EIS、PL等方法对其进行表征,结果表明,镍高度分散在ZSM-5表面上,镍的引入能够加快电子迁移速率,有效降低光生电子空穴的复合几率,拓宽光的响应范围,提高光催化活性。考察了光催化剂的钛与镍负载量、焙烧温度、焙烧时间与光催化剂脱硫性能的关系,结果表明,焙烧温度为550℃、焙烧时间为4 h、TiO_2负载量(质量分数)为15%和NiO质量分数为1. 2%时,光催化剂脱硫效果最佳,对模拟柴油的脱硫率最高达88. 36%。该催化剂具有很好的稳定性和再使用性。
TiO_2/Ni-ZSM-5 catalyst is synthesized by the supersaturation impregnation method. The samples are characterized by XRD,N_2 adsorption-desorption,UV-Vis,EIS and PL. Characterization results show that nickel is only highly dispersed on the surface of ZSM-5,and the addition of nickel can accelerate the migration rate of electrons,effectively reduce the composite probability of photo-generated electron holes,widen the response range of light and improve the photocatalytic activity. It is shown that O_2 and holes play an important role in photocatalytic oxidation desulfurization,which further proves the photocatalytic desulfurization mechanism. The photocatalytic desulfurization effects of photocatalyst are investigated in terms of the loading amount of titanium and nickel,the roasting temperature and the roasting time.The catalyst that is made at a calcination temperature of 550℃,a roasting time of 4 h,15%( w) of TiO_2 loading amount and 1. 2%( w) of Ni O loading amount can give the best desulfurization effect that the highest desulfurization rate for simulated diesel can reach 88. 36%.The catalyst also exhibits good stability and reusability.
引文
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