초록
접촉분해경유(LCO)와 dimethylsulfoxide(DMSO)수용액의 평형추출로부터 얻어진 추출상을 원료로 사용한 역추출에 의해 추출상중의 방향족의 회수를 검토했다. 역추출 용매의 선정을 위해, Benzene, Toluene, m-Xylene(mX), n-Hexane(Hx)과 n-Octane(Ot)을 용매로 사용하여 추출상-용매간의 분배평형을 측정한 결과, 추출상중의 방향족의 회수면에서 Hx이 가장 적절한 용매이었다. 또, Hx을 용매로 사용하여 평형 역추출을 행해 방향족의 회수에 대한 조작인자의 영향을 검토했다. 방향족에 대한 분배계수는 용매/원료(추출상) 질량비(S/F)(S/F를 변화시켜 얻어진 추잔상 혹은 추출상중의 질량분율)에 관계없이 일정했으나 수율은 S/F가 증가함에 따라 증가했다. 조작온도는 방향족의 분배계수와 수율에 영향을 미치지 못했다. 나프탈렌류 성분(탄소수:10~12)간에는 탄소수가 많을수록 분배계수 및 수율이 컸다. 또한, 회분 교반조를 사용하여 역추출을 행해 방향족 성분의 물질이동 속도를 측정했다.
Recovery of aromatics in extract phase which was obtained by batch equilibrium extraction between light cycle oil(LCO) and dimethylsulfoxide(DMSO) solution as solvent was investigated by re-extraction. To select the most suitable re-extraction solvent for recovery of aromatics in extract phase, distribution equilibrium was measured between extract phase and solvents. The solvents used were benzene(B), toluene(T), m-Xylene(mX), n-hexane(Hx) and n-hexane(Hx) and n-Octane(Ot). From the distribution coefficients and yields of aromatics, Hx seemed to be the most suitable. Furthermore, effects of operation parameters for re-extraction of aromatics in the extract phase were studied by batch equilibrium re-extracion with Hx as solvent. Yields of aromatics were found to increase with increasing solvent/feed (extract phase) mass ratio(S/F), while distribution coefficients of aromatics were fixed irrespective of S/F used. Operating temperature did not affect distribution coefficients and yields of aromatics. Distibution coefficients and yields of naphthalene group(carbon numer : 10~12) increased with increasing cabon number. Mass transfer rates of aromatics were also measured with a batch stirred vessel.