Mercury is considered as one of the most toxic heavy metals because of its persistence and bioaccumulation around the world. The release of mercury and some toxic trace metals/metalloids into the environment have an adverse effect to human health and throughout the ecosystem. Among all the anthropogenic mercury emission sources, coal combustion is the major one. In the face of increasingly serious problems of mercury pollution, it has been an urgent issue to protect environment by reducing mercury emission from coal fired power plants. Activated carbon injection is one of the mercury removal approaches which can remove mercury effectively from flue gas using conventional particulate matter controller. However, application of activated carbon sorbents is limited by huge cost, lack of products for low rank fuels. Therefore, it is important to developing alternative cost-effective sorbents or chemical treatments to promote mercury removal capacity of carbonaceous sorbents. Petroleum coke is a low-priced carbon which can be obtained as a vast sum of byproduct from petroleum refinement. With high carbon content, low volatile and ash content, it is a good precursor for preparing high surface AC. Pyrolyzed high-sulfur petroleum exhibited a mercury removal efficiency of around 50-60% at temperatures around 160-170 °C. However, the pyrolysis temperature had to reach to 1100 °C in N_2 atmosphere that could be a heavy burden to apparatus. In this study, mercury adsorption performance of an activated carbon which is derived from petroleum coke (PAC) and modified PAC were evaluated in simulated coal combustion flue gas atmosphere. Potassium hydroxide (KOH) was used as activating agent to obtain PAC by chemical activation. Impregnation method was applied to modify PAC by Mn-Ce binary oxides(MnCe-PAC).
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