School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China.
J Hazard Mater. 2012 Oct 15;235-236:85-91. doi: 10.1016/j.jhazmat.2012.07.013. Epub 2012 Jul 10.
In situ transformation of 4,4'-Dibromobiphenyl (4,4'-DBB) in water was observed with hydrothermal diamond anvil cell (HDAC) up to 633 K. It shows that 4,4'-DBB dissolves in water to form a homogenous phase at the temperature of 588 K and thus subcritical water oxidation of 4,4'-DBB higher than the temperature can be a homogenous phase. To accelerate the oxidative degradation, some Mn-Ce-Co complex oxide nanoparticles of about 100 nm were prepared by co-precipitation hydrothermal method. The nanoparticles show enough stability and catalytic activity for oxidative degradation of 4,4'-DBB in subcritical water. The catalytic activation increases with some Co doping and as for the complex oxides of Mn(1)Ce(1), Mn(0.9)Ce(1)Co(0.1), Mn(0.5)Ce(1)Co(0.5), Mn(0.1)Ce(1)Co(0.9), and Co(1)Ce(1), the Mn(0.9)Ce(1)Co(0.1) presents the best activation. The main intermediate products of degradation are benzoic acid and phenol. The apparent activation energy (E(a)) is 35.92 with 5% Mn(0.9)Ce(1)Co(0.1) as catalyst and 46.69 kJ/mol with no catalyst about the chemical oxygen demand (COD).
在水热金刚石压腔（HDAC）中观察到 4,4'-二溴联苯（4,4'-DBB）的原位转化，温度高达 633 K。结果表明，4,4'-DBB 在 588 K 的温度下溶解在水中形成均相，因此高于该温度的 4,4'-DBB 的亚临界水氧化可以是均相的。为了加速氧化降解，通过共沉淀水热法制备了一些约 100nm 的 Mn-Ce-Co 复合氧化物纳米粒子。纳米粒子在亚临界水中对 4,4'-DBB 的氧化降解表现出足够的稳定性和催化活性。催化活性随着 Co 的掺杂增加而增加，对于 Mn(1)Ce(1)、Mn(0.9)Ce(1)Co(0.1)、Mn(0.5)Ce(1)Co(0.5)、Mn(0.1)Ce(1)Co(0.9)和 Co(1)Ce(1)的复合氧化物，Mn(0.9)Ce(1)Co(0.1)表现出最好的活性。降解的主要中间产物是苯甲酸和苯酚。以 5%Mn(0.9)Ce(1)Co(0.1)为催化剂时，COD 的表观活化能（E(a)）为 35.92 kJ/mol，无催化剂时为 46.69 kJ/mol。
