{"title":"The Thermochemical Conversion of Lactic Acid in Subcritical and Supercritical Water","authors":"Shyh-Ming Chern, Hung-Chi Tu","volume":121,"journal":"International Journal of Chemical and Molecular Engineering","pagesStart":98,"pagesEnd":103,"ISSN":"1307-6892","URL":"https:\/\/publications.waset.org\/pdf\/10006831","abstract":"
One way to utilize biomass is to thermochemically convert it into gases and chemicals. For conversion of biomass, glucose is a particularly popular model compound for cellulose, or more generally for biomass. The present study takes a different approach by employing lactic acid as the model compound for cellulose. Since lactic acid and glucose have identical elemental composition, they are expected to produce similar results as they go through the conversion process. In the current study, lactic acid was thermochemically converted to assess its reactivity and reaction mechanism in subcritical and supercritical water, by using a 16-ml autoclave reactor. The major operating parameters investigated include: The reaction temperature, from 673 to 873 K, the reaction pressure, 10 and 25 MPa, the dosage of oxidizing agent, 0 and 0.5 chemical oxygen demand, and the concentration of lactic acid in the feed, 0.5 and 1.0 M. Gaseous products from the conversion were generally found to be comparable to those derived from the conversion of glucose.<\/p>\r\n","references":"[1]\tB. M. Kabyemela, T. Adschiri, R. M. Malaluan, and K. Arai, \u201cGlucose and fructose decomposition in subcritical and supercritical water: detailed reaction pathway, mechanisms and kinetics,\u201d Industrial & Engineering Chemistry Research, vol. 38, pp. 2888\u20132895, 1999.\r\n[2]\tD. Klingler, and H. Vogel, \u201cInfluence of process parameters on the hydrothermal decomposition and oxidation of glucose in sub- and supercritical water,\u201d The Journal of Supercritical Fluids, vol. 55, pp. 259-270, 2010.\r\n[3]\tD. A. Cantero, L. Vaquerizo, C. Martinez, M. D. Bermejo, and J. M. Cocero, \"Selective transformation of fructose and high fructose content biomass into lactic acid in supercritical water,\" Catalysis Today, vol. 23, in press , 2014.\r\n[4]\tM. Bicker, S. Endres, L. Ott, and H. Vogel, \"Catalytical conversion of carbohydrates in subcritical water: A new chemical process for lactic acid production,\" Journal of Molecular Catalysis A: Chemical, vol. 239, pp. 151-157, 2005.\r\n[5]\tI.G. Lee, M. S. Kim, and S. K. Ihm, \"Gasification of glucose in supercritical water,\" Industrial and Engineering Chemistry Research, vol. 41, pp. 1182-1188, 2002.\r\n[6]\tX. H. Hao, L. J. Guo, X. Mao, X. M. Zhang, and X. J. Chen, \"Hydrogen production from glucose used as a model compound of biomass gasified in supercritical water,\" International Journal of Hydrogen Energy, vol. 28, pp. 55-64, 2003.\r\n[7]\tT. Saito, M. Sasaki, H. Kawanabe, Y. Yoshino, and M. Goto, \"Subcritical water reduction behavior of D-glucose as a model compound for biomass using two different continuous-flow reactor configurations,\" Chemical Engineering and Technology, vol. 32, pp. 527-533, 2009.\r\n[8]\tW. Zeng, D. G. Cheng, H. Zhang, F. Chen, and X. Zhan, \"Dehydration of glucose to levulinic acid over MFI-type zeolite in subcritical water at moderate conditions,\" Reaction Kinetics, Mechanisms and Catalysis, vol. 100, pp. 377-384, 2010.\r\n[9]\tS. M. Chern, and K. T. Hsieh, \u201cThe partial oxidation of acetone in supercritical water,\u201d Super Green 2005 - The 4th International Symposium on Supercritical Fluid Technology for Energy, Environment, and Electronics Applications, Taipei, 2005.\r\n[10]\tH. Tang, and K. Kitagawa, \u201cSupercritical water gasification of biomass: Thermodynamic analysis with direct Gibbs free energy minimization,\u201d Chemical Engineering Journal, vol. 106, pp. 261- 267, 2005.\r\n[11]\tR. L. Smith Jr., T. Adschiri, and K. Arai, \"Energy integration of methane's partial-oxidation in supercritical water and exergy analysis,\" Applied Energy, vol. 71, pp. 205-214, 2002.\r\n[12]\tY. M. Alshammari, and K. Hellgardt, \"Partial oxidation of n-hexadecane through decomposition of hydrogen peroxide in supercritical water,\" Chemical Engineering Research and Design, vol. 93, pp. 565-575, 2015.\r\n[13]\tM. Watanabe, T. Adschiri, and K. Arai, \"Polyethylene decomposition via pyrolysis and partial oxidation in supercritical water,\" Kobunshi Ronbunshu, vol. 58, pp. 631-641, 2001.\r\n[14]\tZ. Y. Ning, Q. Q. Guan, N. Ping, and J. J. Gu, \"Partial oxidation of phenol in supercritical water,\" Advanced Materials Research, vol. 726-731, pp. 2714-2717, 2013.\r\n[15]\tS. N. Reddy, S. Nanda, A. Dalai, and J. A. Kozinski, \"Supercritical water gasification of biomass for hydrogen production,\" International Journal of Hydrogen Energy, vol. 39, pp. 6912-6926, 2014.","publisher":"World Academy of Science, Engineering and Technology","index":"Open Science Index 121, 2017"}