Tao Yong, Wu Chang-Yu, Mazyck David W
Department of Environmental Engineering Sciences, University of Florida, Gainesville, FL 32611-6450, USA.
Chemosphere. 2006 Sep;65(1):35-42. doi: 10.1016/j.chemosphere.2006.03.019. Epub 2006 Apr 21.
Methanol is one of the major hazardous air pollutants emitted from chemical pulp mills. Its collection and treatment is required by the Maximum Achievable Control Technology portion of the 1998 Cluster Rule. The objective of this study is to investigate the technical feasibility of combined adsorption and photocatalytic regeneration for the removal and destruction of methanol. To facilitate the regeneration, activated carbon (AC) was coated with commercially available photocatalyst by a spray desiccation method. Laboratory-scale experiments were conducted in a fixed-bed reactor equipped with an 8 W black light UV lamp (peak wavelength at 365 nm) at the center. The photocatalyst loaded onto AC had no significant impact on the adsorption capacity of the carbon. High humidity was found to greatly reduce the material's capacity in the adsorption and simultaneous adsorption and photocatalytic oxidation of methanol. The photocatalytic regeneration process is limited by the desorption of the adsorbate. Increasing desorption rate by using purge air greatly increased the regeneration capacity. When the desorption rate was greater than the photocatalytic oxidation rate, however, part of the methanol was directly desorbed without degradation.
甲醇是化学制浆厂排放的主要有害空气污染物之一。1998年集群规则的最大可实现控制技术部分要求对其进行收集和处理。本研究的目的是探讨联合吸附和光催化再生去除和破坏甲醇的技术可行性。为便于再生，采用喷雾干燥法将市售光催化剂涂覆在活性炭（AC）上。在装有8W黑光紫外线灯（峰值波长365nm）的固定床反应器中进行了实验室规模的实验。负载在活性炭上的光催化剂对活性炭的吸附容量没有显著影响。发现高湿度会大大降低该材料对甲醇的吸附以及同时进行吸附和光催化氧化的能力。光催化再生过程受吸附质解吸的限制。使用吹扫空气提高解吸速率可大大提高再生能力。然而，当解吸速率大于光催化氧化速率时，部分甲醇会直接解吸而不降解。
