化学工程
化學工程
화학공정
CHEMICAL ENGINEERING
2014年
5期
31-34
,共4页
杨德明%杜鹏%叶梦飞%高晓新
楊德明%杜鵬%葉夢飛%高曉新
양덕명%두붕%협몽비%고효신
甲醇-甲苯%加盐萃取%分配系数%精馏%模拟
甲醇-甲苯%加鹽萃取%分配繫數%精餾%模擬
갑순-갑분%가염췌취%분배계수%정류%모의
methanol-toluene%extraction with salt%partition coefficient%distillation%simulation
研究了加盐萃取分离甲醇-甲苯共沸体系,考察了盐水种类、用量、质量分数及萃取温度等因素对萃取效果的影响,计算了在各种萃取条件下甲醇和甲苯的分配系数。实验结果表明:CaCl2水溶液的萃取效果最好,在CaCl2水溶液质量分数为0.35、萃取温度40℃、溶剂比(体积比)1.5∶1的条件下,甲醇的分配系数为2.32,选择性系数为18200。基于以上实验数据,回归得到了萃取液液相平衡常数与萃取温度关联式的模型参数。在此基础上,提出了加盐萃取-精馏耦合分离甲醇-甲苯3塔工艺流程,并利用Aspen Plus软件中的Extract模拟萃取塔、RadFrac模拟精馏塔,选用NRTL-HOC和ELECNRTL热力学模型,对提出的工艺进行模拟计算,得到了合适的工艺操作条件。模拟结果表明:当萃取塔理论板数为5块;甲醇回收塔理论板数为21块、回流比为1.8;甲苯回收塔理论板数为28块、回流比为2.4时,分离得到的甲醇和甲苯的质量分数分别为0.996和0.997。
研究瞭加鹽萃取分離甲醇-甲苯共沸體繫,攷察瞭鹽水種類、用量、質量分數及萃取溫度等因素對萃取效果的影響,計算瞭在各種萃取條件下甲醇和甲苯的分配繫數。實驗結果錶明:CaCl2水溶液的萃取效果最好,在CaCl2水溶液質量分數為0.35、萃取溫度40℃、溶劑比(體積比)1.5∶1的條件下,甲醇的分配繫數為2.32,選擇性繫數為18200。基于以上實驗數據,迴歸得到瞭萃取液液相平衡常數與萃取溫度關聯式的模型參數。在此基礎上,提齣瞭加鹽萃取-精餾耦閤分離甲醇-甲苯3塔工藝流程,併利用Aspen Plus軟件中的Extract模擬萃取塔、RadFrac模擬精餾塔,選用NRTL-HOC和ELECNRTL熱力學模型,對提齣的工藝進行模擬計算,得到瞭閤適的工藝操作條件。模擬結果錶明:噹萃取塔理論闆數為5塊;甲醇迴收塔理論闆數為21塊、迴流比為1.8;甲苯迴收塔理論闆數為28塊、迴流比為2.4時,分離得到的甲醇和甲苯的質量分數分彆為0.996和0.997。
연구료가염췌취분리갑순-갑분공비체계,고찰료염수충류、용량、질량분수급췌취온도등인소대췌취효과적영향,계산료재각충췌취조건하갑순화갑분적분배계수。실험결과표명:CaCl2수용액적췌취효과최호,재CaCl2수용액질량분수위0.35、췌취온도40℃、용제비(체적비)1.5∶1적조건하,갑순적분배계수위2.32,선택성계수위18200。기우이상실험수거,회귀득도료췌취액액상평형상수여췌취온도관련식적모형삼수。재차기출상,제출료가염췌취-정류우합분리갑순-갑분3탑공예류정,병이용Aspen Plus연건중적Extract모의췌취탑、RadFrac모의정류탑,선용NRTL-HOC화ELECNRTL열역학모형,대제출적공예진행모의계산,득도료합괄적공예조작조건。모의결과표명:당췌취탑이론판수위5괴;갑순회수탑이론판수위21괴、회류비위1.8;갑분회수탑이론판수위28괴、회류비위2.4시,분리득도적갑순화갑분적질량분수분별위0.996화0.997。
The extraction with salt was applied to separate methanol from toluene.The effects of different salt solution,volume,mass fraction and temperature on extraction were studied,and the partition coefficients for methanol and toluene were calculated.The experimental results show that the best extractant is the CaCl2 salt solution,the partition coefficient and the selectivity coefficient of methanol reach up to 2.32 and 18 200 respectively at 40 ℃,salt solution mass fraction 0.35 ,and the volume ratio of salt solution to feed 1 .5 ∶1 .Based on the experimental results,the parameters of the liquid-liquid phase equilibrium comparison expression were determined. The scheme for separating methanol-toluene by combined process of extraction with salt and distillation was put forward.The simulations for the process were performed by Aspen Plus,in which Extrac.module and RadFrac. module were used to simulate extraction column and rectification column respectively.Based on the NRTL-HOC and ELECNRTL thermodynamic models,the suitable operating parameters were obtained.The simulation results show that the mass fraction of methanol and toluene can reach up to 0.996 and 0.997 respectively,under the operating conditions of the theoretical plate of extraction column 5,the theoretical plate of methanol column 21 with a reflux ratio of 1.8,and the theoretical plate of toluene column 28 with a reflux ratio of 2.4.