炼焦煤中有机硫对微波的响应规律

Response regularity of organic sulfur in coking coal to microwave

在固定腔微波反应器中,分别使用不同频率的微波对3种炼焦煤开展脱硫试验,采用XPS分析方法解析微波辐照前后煤中有机硫赋存形态及相对含量的变化,利用Materials Studio模拟平台计算煤中不同有机含硫结构化学键特性在微波作用后的变化,探寻微波作用下煤中有机硫的变化和响应机理。研究表明,山西高硫炼焦煤中有机含硫组分包括硫醇(醚)、噻吩和(亚)砜,840 MHz和915 MHz频率微波辐照后,硫醇(醚)相对含量下降,噻吩相对含量升高,2 450 MH频率微波辐照后,有机含硫组分相对含量变化不明显。模拟计算显示,在外加电场作用下,煤中C—S键长增大、键级减小,有机含硫分子偶极矩增大。说明频率为840 MHz和915 MHz的微波辐照能改变煤中有机硫的化学结构参数,进而影响煤中有机硫的脱除。

This paper investigates the removal of organic sulfur from three kinds of coking coal in the microwave reactor of fixed cavity under the effect of microwaves with different frequencies,as well as analyzes the chemical speciation of sulfur in coal and its relative amount before and after the radiation of microwaves with XPS method. The different features of the organic sulfur structure in the coal will be calculated with the simulated platform of materials studio,so as to explore the variation of organic sulfur in the coal and its response mechanism. The study shows that the organic sulfur group of Shanxi high sulfur coking coal includes mercaptan,thiophene and sulfoxide. After the microwave radiation with the frequencies of 840 MHz and 915 MHz,the relative amount of mercaptan decreases and the relative amount of thiophene increases while there is no obvious change with the relative amount of sulfoxide under the frequency of 2 450 MHz. With the effect of external electric field,the bond length of C—S in the coal increases,the bond order decreases and the molecular dipole moment increases,which shows that the microwave radiation with the frequencies of 840 MHz and 915 MHz can effectively change the composition of organic sulfur in the coal.