Development of a sustainable process for the production of polymer grade lactic acid
Tóm tắt
Lactic acid is a commonly occurring substance in nature, ranging from existence in micro-organisms to the human body. Traditionally, lactic acid has applications in industries such as food, chemicals, pharmaceuticals and textiles. In this work, a sustainable process for the production of polymer grade lactic acid (99 wt. % on dry basis) from crude lactic acid was simulated. The simulation was performed using Aspen Plus® version 8.2. The thermodynamic model used for the process was NRTL – Hayden O’Connell due to the polar nature and non-ideal behavior of the species involved. The process was carried out in three stages. First, crude lactic acid was obtained by reacting calcium lactate with sulfuric acid. The second stage consisted of esterification of lactic acid by reactive distillation. A RadFrac column was used for this purpose which also facilitated easy separation of methyl lactate from methanol and water. Pure methyl lactate obtained from the second stage was then hydrolyzed in the third stage using pure lactic acid as an auto-catalyst to obtain the desired product. Use of pure lactic acid as an auto-catalyst helped to achieve the required purity as it minimized contamination. The process was optimized using sensitivity analysis in Aspen Plus®.
Tài liệu tham khảo
Datta R, Henry M: Lactic acid: recent advances in products, processes and technologies — a review. J Chem Technol Biotechnol. 2006, 81 (7): 1119-1129. 10.1002/jctb.1486. doi:10.1002/jctb.1486
Guilherme A, Silveira M, Fontes C, Rodrigues S, Fernandes F: Modeling and optimization of lactic acid production using cashew apple juice as substrate. Food Bioprocess Technol. 2012, 5 (8): 3151-3158. 10.1007/s11947-011-0670-z. doi:10.1007/s11947-011-0670-z
Södergård A, Stolt M: Industrial Production of High Molecular Weight Poly (Lactic Acid). Poly (Lactic Acid): Synthesis, Structures, Properties, Processing, and Applications. Edited by: Auras R, Lim L-T, Selke SEM, Tsuji H. 2010, Hoboken, NJ, USA: John Wiley & Sons, Inc, doi:10.1002/9780470649848.ch3
Garlotta D: A literature review of poly(lactic acid). J Polym Environ. 2001, 9 (2): 63-84. 10.1023/A:1020200822435. doi:10.1023/A:1020200822435
Qin J, Zhao B, Wang X, Wang L, Yu B, Ma Y, Xu P: Non-sterilized fermentative production of polymer-grade L-lactic acid by a newly isolated thermophilic strain Bacillussp. PLoS ONE. 2009, 4 (2): e4359-10.1371/journal.pone.0004359. doi:10.1371/journal.pone.0004359
John R, Nampoothiri K, Pandey A: Fermentative production of lactic acid from biomass: an overview on process developments and future perspectives. Appl Microbiol Biotechnol. 2007, 74 (3): 524-534. 10.1007/s00253-006-0779-6. doi:10.1007/s00253-006-0779-6
Mehta R, Kumar V, Bhunia H, Upadhyay S: Synthesis of poly(lactic acid): a review. J Macromol Sci Part C. 2005, 45 (4): 325-349. 10.1080/15321790500304148. doi:10.1080/15321790500304148
Tolinski M: Plastics and Sustainability - Towards a Peaceful Coexistence between Bio-Based and Fossil Fuel-Based Plastics. 2012, Salem, Massachussetts: Wiley-Scrivener
Tabone M, Cregg J, Beckman E, Landis A: Sustainability metrics: life cycle assessment and green design in polymers. Environ Sci Technol. 2010, 44 (21): 8264-8269. 10.1021/es101640n.
Henry W: United States Patent 2334524. Purifying hydroxyl-aliphatic acids. 1943, New York
Schopmeyer H, Arnold C: Lactic Acid Purification. 1944, Maine: United States Patent 2350370
Weisberg S, Stimpson E: United States Patent 2290926. Preparation of Lactic Acid. 1942, Baltimore, Maryland
Barve P, Kulkarni B, Nene S, Shinde R, Gupte M, Joshi C, Thite G, Chavan V, Deshpande T: Process for Preparing L(+)-Lactic Acid. 2010, Maharashtra, India: United States Patent 7820859 B2
Stichlmair J, Frey T: Reactive distillation processes. Chem Eng Technol. 1999, 22 (2): 95-103. 10.1002/(SICI)1521-4125(199902)22:2<95::AID-CEAT95>3.0.CO;2-#. doi:10.1002/(SICI)1521-4125(199902)22:2<95::AID-CEAT95>3.0.CO;2-#
Hauan S, Lien K: A phenomena based design approach to reactive distillation. Chem Eng Res Des. 1998, 76 (3): 396-407. 10.1205/026387698524820.