油棕废弃物热解半焦的表面物化结构分析

利用管式炉对油棕废弃物在不同热解终温下进行热解制备半焦焦样,采用同步热分析仪(TG-DTG)、傅里叶红外光谱仪(FTIR)、X射线衍射仪(XRD)对半焦的燃烧性能、表面化学结构及微晶结构进行表征。结果表明:随着升温速率的升高,半焦内部出现燃烧滞后现象,着火温度和燃尽温度升高;随着热解终温的升高,着火变得困难,综合燃烧特性减弱,不利于半焦的燃烧。002峰强度增大,表明半焦的微晶结构有序化程度增高,微晶尺寸La和堆积高度Lc出现先下降后升高的现象,对微晶单元的内部结构和结合缩聚的影响明显;半焦的002峰和100峰的衍射角分别出现在28°和40.5°附近,微晶结构随着热解终温升高向石墨化转变,且石墨化程度增加。

Analysis of Surface Physicochemical Structure of Pyrolysis Product Semi-coke from Oil Palm Wastes

The pyrolysis of semi-coke was prepared by pyrolysis of oil palm wastes at different pyrolysis temperatures using tube furnace. Synchrotron thermal analyzer (TG-DTG), Fourier transform infrared spectrometer (FTIR) and X-ray diffractometer (XRD) were used to characterize the combustibility, surface physicochemical structure and microcrystalline structure of the semi-coke. The results show that: with the increase of heating rate, there is a combustion hysteresis inside the semi-coke, and the ignition temperature and the burnout temperature increase;With the increase of the final temperature of pyrolysis, the ignition becomes difficult and the comprehensive combustion characteristics are weakened, which is not conducive to the burning of semi-coke. The increase of 002 peak intensity indicates that the degree of ordering of microcrystalline structures of semi-coke increases, the crystallite size La and the stacking height Lc appear to decrease first and then increase, which has a significant effect on internal structure and bonding polycondensation of the microcrystalline units. The diffraction angles of the 002 and 100 peak of the semi-coke appear near 28° and 40.5°, the crystallite structure changes to graphitization as the final pyrolysis temperature increases, and the degree of graphitization increases.