煤基柴油与中低温煤焦油沥青共炭化对制备针状焦的影响

Effect of cocarbonization of coal based diesel oil and medium/low temperature coal tar pitch on preparation of needle coke

共炭化法用于针状焦的制备,可调整原料组成和改善炭化过程,可得到品质较好的针状焦。本文以精制的中低温煤焦油沥青为原料,同质柴油馏分(CD)为共炭化剂,利用族组成、红外光谱和核磁共振氢谱分析手段,对不同比例下共炭化的混合原料物化性质进行分析。结合扫描电子显微镜(SEM)、偏光显微镜和X射线衍射仪(XRD)分析手段,考察混合原料组成对制备针状焦的影响。结果表明,煤油的加入可有效调整原料组成,且混合原料制备的针状焦结构得到改善。当煤油的添加质量分数为30%时,脂肪族短侧链的芳烃化合物较多,正庚烷可溶物增加到40.65%,成焦组分正庚烷不溶-甲苯可溶物适中。针状焦中细纤维较多,且有序性和方向性较佳,微晶间距d;为0.34295 nm,片层堆积高度L;为8.67476 nm,片层直径L;为26.49540 nm。

The cocarbonization method is used to prepare needle coke,which can adjust the composition of raw materials and improve the carbonization process to obtain high quality needle coke.In this paper,refined medium and low temperature coal tar pitches were used as raw materials,and homogeneous diesel fraction(CD)was used as cocarbonization agent.The physicochemical properties of mixed raw materials with different cocarbonization ratios were analyzed by means of group composition,infrared spectrum and nuclear magnetic resonance hydrogen spectrum.Scanning electron microscopy(SEM),polarizing microscope and X-ray diffraction(XRD)were used to investigate the influence of the composition of the mixed raw materials on the preparation of needle coke.The results show that kerosene can effectively adjust the composition of raw materials,and the structure of needle coke is improved.When the amount of kerosene is 30%,there are more aromatic compounds with short aliphatic side chains,the n-heptane soluble compounds increase to 40.65%,and the n-heptane insoluble toluene soluble compounds are moderate.There are many fine fiber textures in the needle coke,and the order and directivity are better.The microcrystalline spacing d;is 0.34295 nm,the lamellar stacking height L;is 8.67476 nm and the lamellar diameter L;is 26.49540 nm.