利用轻度炭化的玉米秸秆炭脱除沼气中硫化氢的研究

Study of biogas desulphurization by incomplete carbonated corn stalk biochar

利用专利方法制得轻度炭化的玉米秸秆生物炭,采用电子扫描电镜观察玉米秸秆生物炭的微观结构,利用傅里叶变换红外光谱仪分析生物炭的表面性质。研究结果表明:生物炭较好地保持了玉米秸秆原有的生物结构;生物炭含有大量的木质素、纤维素和少量的未被酸解的半纤维素;碱改性的生物炭主要含有纤维素和碱不溶的木质素,碱处理可改变碱改性生物炭的有机构成和微观结构。采用固定床吸附装置研究了生物炭对沼气中硫化氢的脱除效果,研究发现,水洗炭的脱硫效果较好,高p H值有利于碱改性生物炭对硫化氢的吸附。生物炭对硫化氢的吸附动力学行为可用Bangham速率方程进行描述。

In this study, the incomplete carbonated biochar was made from corn stalks with a patented method. The obtained biochar was flushed with distilled water or modified with alkaline aqueous solution. The micro-structure of biochar was observed with a scanning electron microscope （SEM） and the properties were characterized by a Fourier transform infrared spectroscope （FTIR）. The biological structure of corn stalks was maintained well in the biochar according to the observation of SEM images. Hydroxyl groups could be found in all the biochar samples and ester carbonyl group absorbance peak disappeared in the alkaline modified biochar. The H2S adsorption property of biochar was carried out in a fix-bed setup. The results exhibited that the biochar flushed with water had the best H2S adsorption capacity, high pH value could improve the adsorption properties of biochar. The adsorption process could be well described with the equation of Bangham.