College of Chemical Engineering and Materials Science, Tianjin University of Science & Technology, No. 29 13th Avenue, Economic and Technologic Development Zone, Tianjin, 300457, People's Republic of China.
Environ Sci Pollut Res Int. 2018 Sep;25(26):26046-26058. doi: 10.1007/s11356-018-2640-8. Epub 2018 Jul 3.
In the aim of BTEX leakage emergency, monolithic carbon foam (MCF) was designed and prepared via a simple method. Rice husk char (RHC) was chosen as raw material, polyurethane sponge (PUS) was used as sacrificed template to form inner channel, and corn starch and ZnO were employed as binder and reinforcing filler, respectively. The optimized preparation parameter was determined by adopting of Taguchi experimental design method. Both MCF-RHC and MCF-CAC were made from RHC and commercial activated carbon (CAC) under the same condition, and three reported monolithic carbon adsorbents were selected for comparative study with MCFs. The surface and structural properties were characterized by XRD, SEM, and N adsorption/desorption isotherm analyses. XRD analysis results reveal that MCF-RHC was the composites of carbon, SiO, and ZnO, and MCF-RHC and MCF-CAC have good potential in organic adsorption. Hierarchical structure of MCF was constructed by inner macro-channel from burning up of PUS and micro- and meso-pores from resultant carbon composite, and these inner macro-channels play a more important role in benzene rapid adsorption. Specific surface area of MCF-RHC was 465.5 m g, which included micro- and meso-pores, which mainly come from RHC during the carbonization process. Adsorption kinetics study demonstrated that the benzene equilibrium uptake of MCF-RHC and MCF-CAC was similar, and both of data well fitted the pseudo-second-order kinetic model. However, MCF-RHC has the ability to absorb benzene more quickly, which meets the demand of absorbent utilizing in benzene leakage emergency.
为应对 BTEX 泄漏突发事件，设计并采用简单的方法制备了整体式碳泡沫（MCF）。以稻壳炭（RHC）为原料，聚氨酯海绵（PUS）为牺牲模板形成内通道，玉米淀粉和 ZnO 分别作为粘结剂和增强填料。采用田口实验设计方法确定最佳制备参数。MCF-RHC 和 MCF-CAC 均由 RHC 和商用活性炭（CAC）在相同条件下制备，并选择三种报道的整体式碳吸附剂与 MCF 进行对比研究。通过 XRD、SEM 和 N2 吸附/脱附等温线分析对 MCF 的表面和结构性能进行了表征。XRD 分析结果表明，MCF-RHC 是碳、SiO 和 ZnO 的复合材料，MCF-RHC 和 MCF-CAC 具有良好的有机吸附潜力。通过 PUS 燃烧形成的内宏观通道和由所得碳复合材料形成的微孔和介孔构建了 MCF 的分级结构，这些内宏观通道对苯的快速吸附起着更重要的作用。MCF-RHC 的比表面积为 465.5 m²/g，包括微孔和介孔，主要来自碳化过程中的 RHC。吸附动力学研究表明，MCF-RHC 和 MCF-CAC 的苯平衡吸附量相似，数据均很好地符合准二级动力学模型。然而，MCF-RHC 具有更快吸收苯的能力，满足了苯泄漏突发事件中对吸附剂利用的需求。
