HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

Impact of mechanical and thermo-chemical pretreatments to enhance anaerobic digestion of poly(lactic acid)

Abstract : To date, the introduction of biodegradable plastics such as PLA in anaerobic digestion systems has been limited by a very low rate of biodegradation. To overcome these limitations, pretreatment technologies can be applied. In this study, the impact of pretreatments (mechanical, thermal, thermo-acid, and thermo-alkaline) was investigated. Mechanical pretreatment of PLA improved its biodegradation rate but did not affect the ultimate methane potential (430–461 NL CH4 kg−1 VS). In parallel, thermal and thermo-acid pretreatments exhibited a similar trend for PLA solubilization. Both of these pretreatments only achieved substantial solubilization (>60%) at higher temperatures (120 and 150 °C). At lower temperatures (70 and 90 °C), negligible solubilization (between 1 and 6%) occurred after 48 h. By contrast, coupling of thermal and alkaline pretreatment significantly increased solubilization at the lower temperatures (70 and 90 °C). In terms of biodegradation, thermo-alkaline pretreatment (with 5% w/v Ca(OH)2) of PLA resulted in a similar methane potential (from 325 to 390 NL CH4 kg−1 VS) for 1 h at 150 °C, 6 h at 120 °C, 24 h at 90 °C, and 48 h at 70 °C. Reduction of the Ca(OH)2 concentration (from 5% to 0.5% w/v) highlighted that a concentration of 2.5% w/v was sufficient to achieve a substantial level of biodegradation. Pretreatment at 70 and 90 °C using 2.5% w/v Ca(OH)2 for 48 h resulted in biodegradation yields of 73% and 68%, respectively. Finally, a good correlation (R2 = 0.90) was found between the PLA solubilization and its biodegradation.
Complete list of metadata

Contributor : Sylvie Blanc Connect in order to contact the contributor
Submitted on : Monday, March 14, 2022 - 10:59:23 AM
Last modification on : Friday, May 20, 2022 - 9:04:17 AM



G. Cazaudehore, Remy Guyoneaud, C. Vasmara, Paul Greuet, Emmanuelle Gastaldi, et al.. Impact of mechanical and thermo-chemical pretreatments to enhance anaerobic digestion of poly(lactic acid). Chemosphere, Elsevier, 2022, 297, pp.133986. ⟨10.1016/j.chemosphere.2022.133986⟩. ⟨hal-03607711⟩



Record views