论文部分内容阅读
用在位富氏变换红外光谱技术,测定了SRC沥青烯样品在热解及氧化热解过程中各种功能团的消长动态。当样品在空气中加热时,生成羰基的温度比A-240石油沥青在相同条件下生成同一基团提前40℃,即从190℃提前到150℃。与此同时,生成酚羟基的温度比A-240沥青提前60℃,为170℃。同样品在快速升温条件下经受热氧化时,于360℃生成表征酸酐的1830cm~(-1)吸收峰和表征酯类化合物的1745cm~(-1)吸收峰。氧化反应使脂肪基团快速减少,当反应温度达到420℃时,它们完全消失。沥青烯样品在惰性气流中热解时,脂链裂解以C_α-C_β链断裂为主,烷基的热解脱除比它们在空气气流中氧化消失要慢得多。含氧基团在惰性气流中大都分解消失,惟酚羟基残存。羧基在低温下氧化而生成并积累,但当温度达到350℃时则开始分解。
In-situ Fourier transform infrared spectroscopy was used to measure the growth and decline of various functional groups during pyrolysis and oxidative pyrolysis of SRC asphaltene samples. When the sample was heated in the air, the temperature of carbonyl formation was 40 ℃ earlier than that of A-240 petroleum pitch under the same conditions, ie from 190 ℃ to 150 ℃. In the meantime, the temperature at which phenolic hydroxyl groups were generated was 60 ° C earlier than A-240 bitumen and was 170 ° C. When the same sample was subjected to thermal oxidation under the conditions of rapid heating, the 1830 cm -1 peak representing the anhydride and the 1745 cm -1 peak representing the ester compound were formed at 360 ° C. Oxidation reduces the number of aliphatic groups rapidly, and disappears completely when the reaction temperature reaches 420 ° C. When asphaltene samples pyrolyzed in an inert gas stream, the cleavage of the chains was dominated by the C_α-C_β chain cleavage, and the pyrolytic removal of the alkyl groups was much slower than the disappearance of their oxidation in the air stream. Most of the oxygen-containing groups decompose and disappear in the inert gas flow, but the phenolic hydroxyl groups remain. The carboxyl groups are oxidized and accumulate at low temperatures, but begin to decompose when the temperature reaches 350 ° C.