The removal of organic sulfur and/or water from low-quality coals is the key and foundation in their clean and effective utilization. Ximeng brown coal containing rich organic sulfur was selected as the experimental sample. Effects of the methods and amounts of FeCl3 added into coal on the transformation and release of sulfur were studied in the fixed bed pyrolysis-gas chromatographic analysis apparatus. The results show that methods and amounts of iron added in coal obviously affected the sulfur releasing temperature and the ratio in gases and char. The iron added in coal through mechanical mixing method was mainly dispersed on the surface of coal and had the role of reducing the sulfur released to gas and retaining it in char by formation of Fe1-xS. When iron was added by the method of modified impregnation, it was evenly loaded in coal and ion-exchange occured with the organic functional groups in coal matrix. The action of iron on the transformation of sulfur in the upgrading process of brown coal by pyrolysis changed with the Fe content in impregnation solution. Low content iron promoted the release of sulfur by improving the pyrolysis reactivity of coal, while the role of high loading content iron was mainly to retain sulfur in the char by the reaction between iron and organic sulfur in coal and H2S in gas. Effect of FeCl3 added to coal by different method on the release of COS from the coal pyrolysis primarily presented a promotive action, but the influencing extent was different owing to the distribution of FeCl3 in coal for different methods.%有机硫的脱除与褐煤的提质是低品质煤清洁有效利用的关键.以富含有机硫的锡盟褐煤为研究对象,分别用机械混合和改进的浸渍法负载FeCl3,对其进行固定床热解提质实验研究,以期获得该过程中有机硫的变迁行为及其释放规律.实验结果显示:FeCl3的负载方式及负载量对锡盟褐煤热解提质过程中硫的迁移转化具有较大的影响,机械混合法负载的FeCl3主要负载于煤样表面,抑制了H2S在气相中的释放,以Fe1-xS的形式滞留于焦中;改进的浸渍法负载的FeCl3不仅能够均匀分布于煤中,而且能与煤中有机官能团发生离子交换,负载量较低时铁以催化热解促进硫在气相中释放的作用为主,负载量较高时则主要与煤中的有机硫及气相中的H2S反应生成Fe1-xS而滞留于焦中;不同方式负载的FeCl3对COS的生成基本上呈现出促进作用,但因不同方法引入的FeCl3在煤中分布的均匀性不同,其作用的大小程度不同.
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