化学预氧化对高硫石油焦煅烧脱硫的影响

The effect of chemical pre-oxidation on the thermal desulfurization of high-sulfur petroleum coke

对高硫石油焦采用化学预氧化再经高温煅烧(1 300℃)进行脱硫处理,并采用XRD和SEM对脱硫前后石油焦样品的结构和表面微观形貌进行分析表征。实验结果表明:常压室温下多种化学氧化剂脱硫效果比较,A酸-过氧化氢混合溶液对石油焦脱硫效果最好,其脱硫率达到20.72%;经A酸-过氧化氢混合溶液化学预氧化再高温煅烧(1 300℃)脱硫处理的石油焦的脱硫率相对直接煅烧或者只进行氧化脱硫处理的样品有显著提高,脱硫率可达55%;A酸-过氧化氢混合溶液化学预氧化处理不会破坏煅烧后石油焦存在的石墨雏晶结构,并且促使石油焦表面形成细微裂纹,这有利于煅烧时焦内部硫的逸出以及生产过程中煅烧石油焦原料与煤沥青的结合。

Sulfur in petroleum coke was removed by the desulfurization process of chemical pre-oxidation and then thermal treatment at high temperature （1 300℃） , and the structure and surface microtopography of calcined coke samples after desulfurization were characterized by XRD and SEM analysis. The experimental results showed that, in various chemical oxidants, a mixed solution of A acid-hydrogen peroxide has the best desulfurization effect, with the desulfurization rate of 20.72%, under the conditions of atmospheric pressure and room temperature. The desulphurization efficiency was greatly improved when chemical preoxidized coke samples by a mixed solution of A acid-hydrogen peroxide were thermally treated at high temperature （1 300 ~C） compared with that calcined directly or chemical oxidation only, with the maximum desulphurization of 55% . The process of chemical pre-oxidation by the mixed solution of A acid-hydrogen peroxide would not destroy the graphite crystalline structure of calcined coke and could also prompt petroleum coke surface to form tiny cracks, which is good for sulfur to escape from coke particles when thermally treated and also good for coke in combination with coal tar pitch in the production.