不同形式硫中毒对柴油氧化催化剂性能的影响  

作　　者：李冬旭 罗联伟 

机构地区：[1]湖南道依茨动力有限公司,长沙410000

出　　处：《科技创新与应用》2024年第32期59-62,共4页Technology Innovation and Application

摘　　要：尽管近几年柴油的含硫量大幅度减少,硫中毒依然是影响各种柴油机后处理催化剂性能的最大的因素。这是因为即使是使用超低硫柴油,催化剂随着重型柴油机的使用仍会积累几克的硫。在此次研究中,发现硫中毒对于不同柴油氧化催化剂(DOC)性能的影响取决于催化剂的使用时间。举个例子,把一个硫含量比较少的DOC放在试验台架上测试,结果显示载体性能降低。在另一方面,一些在车上或者台架上运行积累了比较高硫含量的DOC,却没有明显的中毒迹象。可以解释并模拟这种在同一个样件上出现的明显矛盾。所有的试验数据显示,贵金属成分在反应开始发生的时候被选择性地硫化中毒,参与到二氧化硫到三氧化硫的反应。随后,三氧化硫进入涂层基体内,并与贵金属分开,因此极大地降低硫对催化剂性能的影响。Although the sulfur content of diesel has been greatly reduced in recent years,sulfur poisoning is still the most influential factor on the performance of various diesel engine aftertreatment catalysts.This is because even with ultra-low sulfur diesel,the catalyst will still accumulate a few grams of sulfur with the use of heavy-duty diesel engines.In this study,we found that the impact of sulfur poisoning on the performance of different diesel oxidation catalysts(DOC)depends on the time of the catalyst's use.For example:A DOC with relatively low sulfur content was tested on a test bench,and the results showed that the carrier performance was reduced.On the other hand,some DOCs that have accumulated relatively high sulfur content while running on cars or benches show no obvious signs of poisoning.We can explain and simulate this obvious contradiction in the same sample.All test data showed that the precious metal component was selectively sulfided and poisoned at the beginning of the reaction and participated in the reaction from sulfur dioxide to sulfur trioxide.Subsequently,sulfur trioxide enters the coating matrix and is separated from the precious metal,thus greatly reducing the effect of sulfur on catalyst performance.

关 键 词：硫中毒 烘烤试验 脱硫试验 DOC效率 性能 

分 类 号：X701[环境科学与工程—环境工程]