Musmarra D, Karatza D, Lancia A, Prisciandaro M, Mazziotti di Celso G
a Department of Civil Engineering , Design, Building and Environment, Second University of Naples , Aversa (CE), Italy.
b Department of Chemical Engineering, Materials and Industrial Production , University of Naples "Federico II ," Napoli , Italy.
J Air Waste Manag Assoc. 2016 Jul;66(7):698-706. doi: 10.1080/10962247.2016.1170077.
An activated carbon commercially available named HGR, produced by Calgon-Carbon Group, was used to adsorbe metallic mercury. The work is part of a wider research activity by the same group focused on the removal of metallic and divalent mercury from combustion flue gas. With respect to previously published papers, this one is aimed at studying in depth thermodynamic equilibria of metallic mercury adsorption onto a commercial activated carbon. The innovativeness lies in the wider operative conditions explored (temperature and mercury concentrations) and in the evaluation of kinetic and thermodynamic data for a commercially available adsorbing material. In detail, experimental runs were carried out on a laboratory-scale plant, in which Hg° vapors were supplied in a nitrogen gas stream at different temperature and mercury concentration. The gas phase was flowed through a fixed bed of adsorbent material. Adsorbate loading curves for different Hg° concentrations together with adsorption isotherms were achieved as a function of temperature (120, 150, 200°C) and Hg° concentrations (1.0-7.0 mg/m(3)). Experimental runs demonstrated satisfying results of the adsorption process, while Langmuir parameters were evaluated with gas-solid equilibrium data. Especially, they confirmed that adsorption capacity is a favored process in case of lower temperature and they showed that the adsorption heat was -20 kJ/mol. Furthermore, a numerical integration of differential equations that model the adsorption process was proposed. Scanning electron microscopy (SEM) investigation was an useful tool to investigate about fresh and saturated carbon areas. The comparison between them allowed identification of surface sites where mercury is adsorbed; these spots correspond to carbon areas where sulfur concentration is greater.
Mercury compounds can cause severe harm to human health and to the ecosystem. There are a lot of sources that emit mercury species to the atmosphere; the main ones are exhaust gases from coal combustion and municipal solid waste incineration. Furthermore, certain CO2 capture processes, particularly oxyfuel combustion in a pulverized fuel coal-fired power station, produce a raw CO2 product containing several contaminants, mainly water vapor, oxygen, and nitrogen but also mercury, that have to be almost completely removed; otherwise these would represent a strong drawback to the success of the process.
使用卡尔冈炭素集团生产的一种市售活性炭HGR吸附金属汞。这项工作是该团队更广泛研究活动的一部分，该研究活动聚焦于从燃烧烟道气中去除金属汞和二价汞。与之前发表的论文相比，本文旨在深入研究金属汞在商用活性炭上吸附的热力学平衡。其创新性在于探索了更广泛的操作条件（温度和汞浓度），并对一种商用吸附材料的动力学和热力学数据进行了评估。具体而言，实验在实验室规模的装置上进行，其中Hg°蒸气在不同温度和汞浓度下通过氮气流供应。气相流经吸附剂材料的固定床。获得了不同Hg°浓度下的吸附质负载曲线以及作为温度（120、150、200°C）和Hg°浓度（1.0 - 7.0 mg/m³）函数的吸附等温线。实验运行证明了吸附过程的良好结果，同时利用气固平衡数据评估了朗缪尔参数。特别是，他们证实了在较低温度下吸附容量是一个有利过程，并且表明吸附热为 -20 kJ/mol。此外，还提出了对模拟吸附过程的微分方程进行数值积分。扫描电子显微镜（SEM）研究是研究新鲜和饱和碳区域的有用工具。两者之间的比较有助于识别汞吸附的表面位点；这些位点对应于硫浓度较高的碳区域。
汞化合物会对人类健康和生态系统造成严重危害。有许多向大气排放汞物种的来源；主要来源是煤炭燃烧废气和城市固体废物焚烧。此外，某些二氧化碳捕集过程，特别是粉煤燃烧电站的富氧燃烧，会产生一种含有多种污染物的粗二氧化碳产物，主要有水蒸气、氧气和氮气，但也有汞，这些污染物几乎必须完全去除；否则这些将成为该过程成功的严重障碍。
