煤沥青与石油沥青共混改性及其热解特性

Modification of petroleum asphalt with coal tar pitch extract and pyrolysis properties

考察了不同添加量的煤沥青四氢呋喃萃取物(THFS)对石油沥青的改性,随着THFS添加量的增多,改性沥青针入度降低,软化点升高,延度下降,参照英国标准(BSI BS—3690)得出最佳添加量为8%。利用TG-FTIR、FTIR对改性沥青进行了表征,结果表明:THFS、改性沥青的失重率大于基质沥青70的失重率;THFS在700~900cm^(-1)处芳香烃类的透射峰强度明显强于基质沥青与改性沥青;沥青老化后在2953cm^(-1)和1377cm^(-1)(—CH_3)、1461cm^(-1)和2924cm^(-1)(—CH_2—)处透射峰逐渐增强;1600cm^(-1)(C=O和苯环C=C)透射峰逐渐增强;沥青热解半焦中的脂肪烃类物质含量较少,主要以高度缩合的稠环芳香烃类物质为主;沥青在老化过程中主要发生了氧化、裂解、加成、聚合、缩合等反应。

This paper discusses different amounts of coal tar pitch tetrahydrofuran extracts（THFS） for petroleum asphalt modification. With the increase of added amount of THFS,penetration of modified asphalt decreases,softening point increases,and ductility decreases. Referring to British Standards（BSI BS-3690）,optimum dosage is 8%. TG-FTIR and FTIR characterization indicates that mass losses of THFS and modified asphalt are higher than that of base asphalt 70 Transmission peak intensity of THFS at 700900cm-1（aromatic hydrocarbons） is significantly stronger than that of asphalt and modified asphalt. Transmission peaks of asphalt after aging at 2953cm-1 and 1377cm-1（—CH3）,1461cm-1 and 2924cm-1（—CH2—） gradually increase. Transmission peak at 1600cm-1（C=O and benzene ring C=C） gradually increases. Pyrolysis residue of asphalt has less content of aliphatic hydrocarbon,while higher content of condensed polycyclic aromatic hydrocarbons. Oxidation,pyrolysis,addition,polymerization,and condensation mainly occur during asphalt aging.