UK Biochar Research Centre, School of GeoSciences, University of Edinburgh, Alexander Crum Brown Road, Edinburgh EH9 3FF, United Kingdom.
UK Biochar Research Centre, School of GeoSciences, University of Edinburgh, Alexander Crum Brown Road, Edinburgh EH9 3FF, United Kingdom.
Bioresour Technol. 2021 Feb;321:124473. doi: 10.1016/j.biortech.2020.124473. Epub 2020 Dec 2.
Magnetic carbons can significantly lower the costs of wastewater treatment due to easy separation of the adsorbent. However, current production techniques often involve the use of chlorinated or sulfonated Fe precursors with an inherent potential for secondary pollution. In this study, ochre, an iron-rich waste stream was investigated as a sustainable Fe source to produce magnetic activated biochar from two agricultural feedstocks, softwood and wheat straw. Fe doping resulted in significant shifts in pyrolysis yield distribution with increased gas yields (+50%) and gas energy content (+40%) lowering the energy costs for production. Physical activation transformed ochre to magnetite/maghemite resulting in activated magnetic biochars and led to a 4-fold increase in the adsorption capacities for two common micropollutants - caffeine and fluconazole. The results show that Fe doping not only benefits the adsorbent properties but also the production process, leading the way to sustainable carbon adsorbents.
磁性碳由于易于分离吸附剂，可以显著降低废水处理成本。然而，目前的生产技术通常涉及使用氯化或磺化的 Fe 前体，存在潜在的二次污染。在这项研究中，褐铁矿（一种富含铁的废物流）被用作一种可持续的 Fe 源，用于从两种农业原料（软木和麦秆）生产磁性生物炭。Fe 掺杂导致热解产率分布发生显著变化，增加了气体产率（+50%）和气体能量含量（+40%），降低了生产的能源成本。物理活化将褐铁矿转化为磁铁矿/磁赤铁矿，从而形成了活化磁性生物炭，使两种常见的微污染物（咖啡因和氟康唑）的吸附容量增加了 4 倍。结果表明，Fe 掺杂不仅有利于吸附剂的性能，而且有利于生产过程，为可持续碳吸附剂开辟了道路。
