以TiCl_4为钛源,采用简单易行的溶胶凝胶法低温制备锐钛矿型TiO_2光催化剂。采用XRD、SEM、DRS和LRS等手段对所制备的锐钛矿型TiO2催化剂的结构进行了表征。通过光催化还原U(Ⅵ)效果研究了锐钛矿型TiO_2光催化剂的光催化还原活性。结果...以TiCl_4为钛源,采用简单易行的溶胶凝胶法低温制备锐钛矿型TiO_2光催化剂。采用XRD、SEM、DRS和LRS等手段对所制备的锐钛矿型TiO2催化剂的结构进行了表征。通过光催化还原U(Ⅵ)效果研究了锐钛矿型TiO_2光催化剂的光催化还原活性。结果表明,催化剂在紫外光区有较强的吸收,纳米锐钛矿型TiO_2的吸收带边分别为398 nm,纳米TiO_2样品的禁带宽度为3.14 e V。锐钛矿型TiO_2对U(Ⅵ)的光催化还原活性可达到99%。为高效光催化还原技术处理低浓度含铀废水提供实验依据。展开更多
The heat-activated sepiolite,which was prepared using sepiolite by thermal treatment at different temperatures,was used as an absorbent for the removal of rhodamine B（RhB） from aqueous solutions.The structure and mo...The heat-activated sepiolite,which was prepared using sepiolite by thermal treatment at different temperatures,was used as an absorbent for the removal of rhodamine B（RhB） from aqueous solutions.The structure and morphology of the as-prepared samples were characterized by X-ray diffraction（XRD） and scanning electron microscopy（SEM） techniques,respectively.The adsorption capacity of RhB onto the heat-activated sepiolite has been examined with pH,adsorbent dosage,contact time,initial dye concentration,and temperature.Kinetic studies showed that the equilibrium was attained within 40 min,and the kinetic data were well described by the pseudo-second-order kinetic model.Besides,the experimental data（R 2 〉0.999） fitted the Freundlich model better than the Langmuir model.The as-prepared sample showed higher adsorption capacity（8.33 mg/g） for the removal of RhB than that of sepiolite,which could be attributed to more adsorption sites caused by appropriate heat treatment.The adsorbent can be well regenerated by calcination at 400 ℃ for 2 h and regenerated sepiolite did not exhibited significant loss of adsorption activity after five recycles.展开更多
文摘以TiCl_4为钛源,采用简单易行的溶胶凝胶法低温制备锐钛矿型TiO_2光催化剂。采用XRD、SEM、DRS和LRS等手段对所制备的锐钛矿型TiO2催化剂的结构进行了表征。通过光催化还原U(Ⅵ)效果研究了锐钛矿型TiO_2光催化剂的光催化还原活性。结果表明,催化剂在紫外光区有较强的吸收,纳米锐钛矿型TiO_2的吸收带边分别为398 nm,纳米TiO_2样品的禁带宽度为3.14 e V。锐钛矿型TiO_2对U(Ⅵ)的光催化还原活性可达到99%。为高效光催化还原技术处理低浓度含铀废水提供实验依据。
基金Supported by the Key Project of Chinese Ministry of Education(108164)National Key Technology Research and Development Program of China(2006BAJ04A09-2,2008BAJ08B13-04)
文摘The heat-activated sepiolite,which was prepared using sepiolite by thermal treatment at different temperatures,was used as an absorbent for the removal of rhodamine B（RhB） from aqueous solutions.The structure and morphology of the as-prepared samples were characterized by X-ray diffraction（XRD） and scanning electron microscopy（SEM） techniques,respectively.The adsorption capacity of RhB onto the heat-activated sepiolite has been examined with pH,adsorbent dosage,contact time,initial dye concentration,and temperature.Kinetic studies showed that the equilibrium was attained within 40 min,and the kinetic data were well described by the pseudo-second-order kinetic model.Besides,the experimental data（R 2 〉0.999） fitted the Freundlich model better than the Langmuir model.The as-prepared sample showed higher adsorption capacity（8.33 mg/g） for the removal of RhB than that of sepiolite,which could be attributed to more adsorption sites caused by appropriate heat treatment.The adsorbent can be well regenerated by calcination at 400 ℃ for 2 h and regenerated sepiolite did not exhibited significant loss of adsorption activity after five recycles.
