Applied Chemistry for Engineering (공업화학)

The Korean Society of Industrial and Engineering Chemistry (한국공업화학회)
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Separation and Purification of 2,6-Dimethylnaphthalene Present in the Fraction of Light Cycle Oil by Crystallization Operation

결정화조작에 의한 접촉분해경유 유분에 함유된 2,6-디메틸나프탈렌의 분리·정제

  • Kim, Su Jin (Department of Chemical Engineering, Chungwoon University)
  • Received : 2018.07.15
  • Accepted : 2018.08.06
  • Published : 2018.12.10
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Abstract

The separation and purification of 2,6-dimethylnaphthalene (2,6-DMN) present in the light cycle oil (LCO) fraction was investigated by a crystallization operation. Solute crystallization (SC) was performed using LCO fraction and iso-propyl alcohol as a raw material and a SC solvent, respectively. Increasing the operation temperature and volume ratio of the solvent to the raw material (S/F) resulted in improving the purity of 2,6-DMN, whereas the yield decreased. As a result of the crystallization operation in three steps containing the SC using LCO fraction (13.9% 2,6-DMN) and isopropyl alcohol, the re-crystallization 1 (RC 1) using the crystals recovered by SC and methyl acetate, and RC 2 using the crystals recovered by RC 1 and methyl acetate, the crystal with 99.9% 2,6-DMN was recovered with 19.5% yield. Furthermore, the separation and purification process of 2,6-DMN present in the LCO fraction was reevaluated by using the experimental results obtained through each operations of SC, RC 1, and RC 2.

결정화조작에 의해 접촉분해경유(LCO) 유분 중에 함유된 2,6-디메틸나프탈렌(2,6-DMN)의 분리 정제를 검토했다. LCO 유분을 원료로, 이소프로필알코올을 결정화 용매로 각각 사용하여 solute crystallization (SC)을 수행했다. 결정화 조작온도의 상승과 용매/원료의 체적비(S/F)의 증가는 2,6-DMN의 순도를 향상시켰으나, 역으로 수율의 저하를 초래시켰다. LCO 유분(13.9% 2,6-DMN)과 이소프로필알코올을 사용한 SC, SC에 의해 회수한 결정과 메틸아세테이트를 사용한 re-crystallization 1 (RC 1), RC 1에 의해 회수한 결정과 메틸아세테이트를 사용한 RC 2의 3단계로 결정화조작을 행한 결과, 19.5%의 수율로 99.9% 2,6-DMN의 결정을 회수할 수 있었다. SC, RC 1, RC 2의 각 조작을 통해 얻어진 실험적 결과를 이용하여 LCO 유분 중에 함유된 2-6-DMN의 분리 정제공정을 검토했다.

Keywords

GOOOB2_2018_v29n6_799_f0001.png 이미지

Figure 1. Schematic diagram of batch crystallization apparatus[2,13]. 1: circulator, 2: PID controller, 3: digital thermometer, 4: variablespeed mixer, 5: crystallizer with a double jacket, 6: glass filter, 7: aspirator.

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Figure 2. Solvent comparison for purification of 2,6-DMN (without washing) at SC. Feed used: Feed I, solvent used: 1 Isopropyl alcohol, 2 Methanol, 3 Ethanol, 4 Hexane, 5 Methanol (60 vol%) + acetone, 6 Acetonitrile, 7 Heptane, 8 Isopropyl ether, 9 Methyl acetate, 10 Isopropyl acetate, 11 Acetone, 12 Ethyl acetate.

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Figure 3. Effect of (a) impeller speed (N) and operating time (t), and (b) volume ratio (S/F) and operation temperature (T) for purification of 2,6-DMN (without washing) through SC. Feed used: Feed I. Keys: (a) ● N (t = 1 h), y2,6-DMN,SC, ▲ N (t = 1 h), Y2,6-DMN,SC, ○ t (N = 2.5 s-1), y2,6-DMN,SC, △ t (N = 2.5 s-1), Y2,6-DMN,SC, and (b) ▲ S/F (T = -20 ℃), ▽ T (S/F = 9).

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Figure 4. Change of purity and yield of 2,6-DMN and 2,7-DMN according as each operation. Conditions: SC (Feed used: Feed I, solvent used: isopropyl alcohol, without washing, S/F = 1, T = -15 ℃, N = 2.5 s1, t = 1 h), RC 1 (Feed used: Feed II, solvent used: methyl acetate, without washing, S/F = 5, T = -20 ℃, N = 2.5 s1, t = 1 h), RC 2 (Feed used: Feed III, solvent used: methyl acetate, with washing using methyl acetate, S/F = 9, T = -20 ℃, N = 2.5 s1, t = 1 h).

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Figure 5. Separation and purification process of 2,6-DMN from LCO fraction. Tower nos. 1, 3, 4: crystallization towers; Tower nos. 2, 5: distillation towers; Tower no. 6: washing tower; 7: dryer; tank nos. 8, 9: dissolution tanks; 10: isomerization reactor. MA: methyl acetate, IPA: isopropyl alcohol.

Table 1. Material Systems and Experimental Conditions for Each Operation

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Table 2. Composition of LCO Fraction (Feed 1) and Crystal Recovered via Each Operation

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References

  1. H. C. Kang and S. J. Kim, Separation of 2,6-dimethylnaphthalene in dimethylnaphthalene isomers mixture by crystallization operation, Appl. Chem. Eng., 25, 116-120 (2014). https://doi.org/10.14478/ace.2013.1118
  2. S. J. Kim and H. J. Jeong, High-purity purification of 2,6-dimethylnaphthalene (2,6-DMN) in Light cycle oil-Purification of 2,6-DMN from concentrate of DMN isomers by crystallization-, Appl. Chem. Eng., 19, 105-110 (2008).
  3. S. J. Kim and S. C. Kim, Separation and recovery of dimethlnaphthalene isomers from light cycle oil by distillation-extraction combination, Sep. Sci. Technol., 38, 4097-4118 (2003).
  4. S. J. Kim, R. Egashira, and J. Kawasaki, Extraction of aromatics in the light cycle oil - Extraction equilibrium and extraction rate of naphthalene group, J. Japan Pet. Inst., 38, 114-120 (1995). https://doi.org/10.1627/jpi1958.38.114
  5. S. J. Kim, S. C. Kim, and J. Kawasaki, Separation and recovery of bicyclic aromatic components in the light cycle oil, Sep. Sci. Technol., 38, 179-199 (2003). https://doi.org/10.1081/SS-120016705
  6. S. J. Kim and S. C. Kim, Separation of valuable bicyclic aromatic components from light cycle oil by an emulsion liquid membrane, Sep. Sci. Technol., 39, 1093-1109 (2004).
  7. T. A. Al-Sahhaf and E. Kapetanovic, Measurement and prediction of phase equilibria in the extraction of aromatics from naphtha reformate by tetraethylene glycol, Fluid Phase Equilib., 118, 271-285 (1996). https://doi.org/10.1016/0378-3812(95)02849-8
  8. G. R. Vakili-Nezhaad, H. Modarress, and G. A. Mansoori, Thermodynamic modeling and experimental studies of dearomatization process from a complex petroleum fraction, Sep. Sci. Technol., 35, 743-754 (2000). https://doi.org/10.1081/SS-100100188
  9. G. M.Radwan, S. A. Al-Muhtaseb, and M. A. Fahim, Liquid-liquid equilibria for the extraction of aromatics from naphtha reformate by dimethylformamide/ethylene glycol mixed solvent, Fluid Phase Equilib., 129, 175-186 (1997). https://doi.org/10.1016/S0378-3812(96)03179-2
  10. T. T. Jiao, X. L. Zhuang, H. Y. He, C. S. Li, H. N. Chen, and S. J. Zhang, Separation of phenolic compounds from coal tar via liquid-liquid extraction using amide compounds, Ind. Eng. Chem. Res., 54, 2573-2579 (2015). https://doi.org/10.1021/ie504892g
  11. H. C. Kang and S. J. Kim, Comparison of methanol with formamide on separation of nitrogen heterocyclic compounds from model coal tar fraction by batch cocurrent multistage equilibrium extraction, Polycycl. Aromat. Compd., 36, 754-757 (2016).
  12. S. J. Kim and Y. J. Chun, Separation of nitrogen heterocyclic compounds from model coal tar fraction by solvent extraction, Sep. Sci. Technol., 40, 2095-2109 (2005). https://doi.org/10.1081/SS-200068488
  13. S. J. Kim, Separation and purification of indole in model coal tar fraction of 9 compounds system, Polycycl. Aromat. Compd., Doi:10.1080/10406638.2016.1259170 (2016).
  14. R. Egashira and J. Kawasaki, Decrease in aromatics content in motor gasoline by O/W/O emulsion liquid membrane process, J. Japan Pet. Inst., 40, 107-114 (1997). https://doi.org/10.1627/jpi1958.40.107
  15. S. J. Kim, H. C. Kang, Y. S. Kim, and H. J. Jeong, Liquid membrane permeation of nitrogen heterocyclic compounds contained in model coal tar fraction, Bull. Korean Chem. Soc., 31, 1143-1148 (2010). https://doi.org/10.5012/bkcs.2010.31.5.1143
  16. A. Sharma, A. N. Goswami, B. S. Rawat, and R. Krishina, Effect of surfactant type on selectivity for the separation of 1-methylnaphthalene from dodecane using liquid membranes, J. Membr. Sci., 32, 19-30 (1987). https://doi.org/10.1016/S0376-7388(00)81571-9
  17. M. Motoyuki, K. Yamamoto, S. Yoshida, S. Yamamoto, A. V. Sapre, J. P. McWilliams, S. P. Donnelly, and S. D. Hellring, Isomerization of dimethylnaphthalene to produce 2,6-dimethylnaphthalene, US Patent 6,018,087 (2000).
  18. Y. Yamamoto, Y. Sato, T. Ebina, C. Yokoyama, S. Takahasi, Y. Mito, H. Tanabe, N. Nishiguchi, and K. Nagaoka, Separation of high purity indole from coal tar by high pressure crystallization, Fuel, 70, 565-566 (1991). https://doi.org/10.1016/0016-2361(91)90039-D
  19. M. Motoyuki, K. Yamamoto, A. V. Sapre, J. P. McWilliams, and S. P. Donnelly, Process for preparing 2,6-dimethylnaphthalene, US Patent 6,018,086 (2000).
  20. H. Uchida, Y. Iwai, M. Amiya, and Y. Arai, Adsorption behaviors of 2,6-and 2,7-dimethylnaphthalenes in supercritical carbon dioxide using NaY-type zeolite, Ind. Eng. Chem. Res., 36, 424-429 (1997). https://doi.org/10.1021/ie960364t
  21. I. Mochida, Y. Q. Fei, and K. Sakanishi, Capture and recovery of basic nitrogen species in coal tar pitch using nickel sulfate as adsorbent, Chem. Lett., 515-518 (1990).
  22. S. Hall, R. Tang, J. Baeyens, and R. Dewil, Removing polycyclic aromatic hydrocarbons from water by adsorption on silicagel, Polycycl. Aromat. Compd., 29, 160-183 (2009). https://doi.org/10.1080/10406630903017534
  23. M. Motoyuki, K. Yamamoto, A. V. Sapre, and J. P. McWilliams, Process for preparing dialkylnaphthalene, US Patent 6,011,190 (2000).

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