神华煤直接液化残渣萃取组分改性石油沥青

Modified asphalt with the extract fractions of Shenhua direct coal liquefaction residue

以神华煤直接液化残渣索氏溶剂梯级萃取分别得到的重油(HS)、沥青烯(AS)和前沥青烯(PA)作为改性剂,对石油沥青进行改性,探究改性剂的掺混量对石油沥青性能的影响及其改性机制。研究表明:当HS作为改性剂时,最佳掺混量为1%;当AS作为改性剂时,最佳掺混量为4%;PA作为改性剂时得到的改性沥青,针入度和延度不能同时符合美国ASTM D5710—95标准40~55针入度的指标要求;HS和AS改性沥青与石油沥青相比在2924cm^(–1)及2847cm^(–1)处的—CH2—的伸缩振动吸收峰强度变弱,在改性过程中可能发生了烷基侧链脱氢反应;改性沥青与石油沥青的热失重相比,其最终失重温度都有所提高,当AS作为改性剂、加入量为4%时改性沥青最终失重温度提高最大为11℃;随着改性剂分子量的增大,其荧光显微镜图片中的荧光物质会越来越多,颗粒逐渐增大。

The petroleum asphalt was modified by three fractions extracted from Shenhua direct coal liquefaction residue[hexane soluble(HS),asphaltene(AS)and preasphaltene(PA)].The optimum of modifiers and mechanism were studied.The optimal conditions were as follows:the optimum amount of HS has been found to be1%and AS to asphalt ratio of4%,however the penetration and ductility of PA-modified asphalt can't meet the specifications of ASTM D5710-9540-55penetration grade designated for modified asphalts at the same time.The modified asphalts were investigated by FTIR.The involvement of modifiers(HS,AS)decreased the stretching vibration of aliphatics(-CH2-)of modified asphalt at2924cm-1and2847cm-1.The results showed that the involvement may cause dehydrogenation reaction of the alkyl side chain.TG and DTG curves of modified asphalt and petroleumasphalt were basically the same,but the ultimate weight loss temperature was increased.For example,the maxium increasing temperature of4%AS/90reached11℃.The much larger size of the fluorescent substance with larger molecular of modifiers can be seen from the fluorescence microscopy images.