Abstract

It is very necessary to produce bio-activated carbon for special use with easy procedure and low cost. One kind of huge surface area microporous bio-material was successfully prepared from agricultural residues (peanut shell, Arachis hypogaea Linn.) and beneficially applied to control elemental mercury (Hg⁰) in simulated coal-fired flue gas in this study. The possible effects of experimental factors including activator, reaction temperature, and flue components were investigated. The physicochemical properties of the prepared adsorbents were characterized by Brunauer-Emmett-Teller (BET), scanning electron microscopy with energy-dispersive X-ray spectrometry (SEM-EDX), and X-ray photoelectron spectroscopy (XPS). The results indicated that the peanut shell activated carbon presented excellent Hg⁰ removal efficiency near 90% at 150 °C. The characterization analysis indicated that the removal characteristics were governed by both physical adsorption and chemical adsorption. The chemisorbed mercury on the activated carbon was mainly distinguished into mercuric chloride (HgCl₂) and mercuric oxide (HgO). The presence of C-Cl and O* promoted Hg⁰ into HgCl₂ and HgO. Zinc chloride could not only improve the micropore quantity of activated carbon but also have remarkably positive effects on the elemental mercury removal. This study provided a practical and easy preparation method of bio-activated carbon for Hg⁰ removal with low cost.

Graphical Abstract

中文翻译：

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Arachis hypogaea Linn消除了烟气中的汞元素。外壳产生活性炭。

摘要

生产易于使用且成本低廉的特殊用途的生物活性炭非常必要。从农业残留物（花生壳，花生，花生）成功制备了一种大表面积的微孔生物材料，并有益地用于控制元素汞（Hg ⁰这项研究中的模拟燃煤烟气中）。研究了包括活化剂，反应温度和烟道成分在内的实验因素的可能影响。通过Brunauer-Emmett-Teller（BET），具有能量色散X射线能谱的扫描电子显微镜（SEM-EDX）和X射线光电子能谱（XPS）来表征所制备的吸附剂的理化性质。结果表明，花生壳活性炭在150°C时具有极好的Hg ⁰去除率，接近90％。表征分析表明，其去除特性受物理吸附和化学吸附的控制。活性炭上化学吸附的汞主要分为氯化汞（HgCl ₂）和氧化汞（HgO）。C-Cl和O *的存在将Hg ⁰提升为HgCl ₂和HgO。氯化锌不仅可以提高活性炭的微孔数量，而且对元素汞的去除也具有明显的积极作用。这项研究为低成本，低成本地去除Hg ⁰提供了一种实用，简便的生物活性炭制备方法。