Properties and oxidation of exhaust particulates from dual fuel combustion: A comparative study of premixed gasoline, n-butanol and their blends.
Properties and oxidation of exhaust particulates from dual fuel combustion: A comparative study of premixed gasoline, n-butanol and their blends.
复制标题
DOI：
10.1016/j.envpol.2020.116391
复制
发表时间：
2020-12
影响因子：
8.9
通讯作者：
Xiaochen Wang;Ying Wang;Yuanqi Bai;Qimeng Duan
中科院分区：
文献类型：
--
作者：
Xiaochen Wang;Ying Wang;Yuanqi Bai;Qimeng Duan
本对比研究的重点是评价双燃料燃烧与各种低反应性燃料的排气颗粒物的氧化行为和相关性质。采用高分辨透射电子显微镜（HR-TEM）、拉曼光谱（RS）、X射线光电子能谱（XPS）和热重分析（TG）对汽油、正丁醇和固定取代度为40%的汽油/正丁醇混合物（分别记为G40、B40和G20 B20）进行了表征。TG结果表明，双燃料燃烧颗粒物的氧化活性大小顺序为G40 > G20 B20> B40，且上述颗粒物的氧化活性高于柴油机碳烟。可以推断，与正丁醇/柴油双燃料燃烧相比，应用汽油/柴油双燃料燃烧对柴油颗粒过滤器的再生甚至寿命具有有益的影响。与G40相比，B40具有更有序的纳米结构，HR-TEM显示的条纹长度更长，但弯曲度更小，RS显示的ID 1/IG和ID 3/IG值更低。注意，B40和G20 B20样品之间的碳烟纳米结构的差异很小，实际上预混合燃料对碳烟反应性和纳米结构的影响都很小。因此，烟灰反应性仅部分地受结构控制。此外，TEM图像显示，预混丁醇的碳烟比预混汽油的碳烟具有更小的初级颗粒。从双燃料燃烧的颗粒物表现出较高的C-OH浓度比柴油烟尘，但没有显着的趋势可以观察到C双键O浓度之间的各种样品。一次颗粒尺寸和含氧表面官能团与碳烟氧化反应性无关。
The focus of this comparative study was to evaluate the oxidation behavior and related properties of exhaust particulates from dual fuel combustion with various low reactivity fuels. Samples from premixed gasoline, n-butanol and gasoline/n-butanol blends with a fixed substitution of 40% (noted as G40, B40 and G20B20, respectively) were characterized by high-resolution transmission electron microscope (HR-TEM), Raman spectroscopy (RS) and X-ray photoelectron spectroscopy (XPS) and thermogravimetric (TG). TG results showed that the oxidation reactivity of particulates from dual fuel combustion followed the order of G40 > G20B20 > B40, and above particles were more reactive to oxidation than diesel soot. It can be inferred that applying gasoline/diesel dual fuel combustion has beneficial implications for the diesel particulate filter regeneration and even lifetime, in comparison to n-butanol/diesel dual fuel combustion. In comparison to G40 soot, B40 soot exhibited a more ordered nanostructure with longer fringe length but shorter tortuosity from HR-TEM as well as lowerID1/IGandID3/IGvalues from RS. Note that the differences in the soot nanostructure between B40 and G20B20 samples were low, and actually the effects of premixed fuels on both soot reactivity and nanostructure were slight. Hence, soot reactivity is only partially structure-controlled. In addition, TEM images showed that soot from premixed butanol had smaller primary particle than premixed gasoline. Particulates from dual fuel combustion exhibited higher C–OH concentrations than diesel soot, but no significant trend can be observed for Cdouble bondO concentrations among various samples. Both primary particle size and oxygenated surface functional groups were not correlated with soot oxidation reactivity.