| Title |
Insights on the hydrogel-forming ability and post-gelling mechanical properties of structural extracellular polymeric substances (sEPS) from aerobic granular sludge (AGS): A comparison with model biopolymers |
| ID_Doc |
13516 |
| Authors |
Pagliaccia, B; Durieux, S; Bessiere, Y; Bounouba, M; Sarkis, AB; Girbal-Neuhauser, E; Carretti, E; Lubello, C; Lotti, T; Paul, E |
| Title |
Insights on the hydrogel-forming ability and post-gelling mechanical properties of structural extracellular polymeric substances (sEPS) from aerobic granular sludge (AGS): A comparison with model biopolymers |
| Year |
2022 |
| Published |
|
| DOI |
10.1016/j.jwpe.2022.103076 |
| Abstract |
The hydrogel-forming ability and post-gelling mechanical properties of structural extracellular polymeric sub-stances (sEPS) extracted from aerobic granular sludge (AGS) were studied in comparison to well-known bio-polymers (i.e., alginate and kappa/iota-carrageenan) taking advantage of material-saving, reproducible and robust experimental protocols. With respect to alginate and kappa-carrageenan, sEPS and iota-carrageenan hydrogels formed in presence of divalent metal ions M2+ behaved similarly once subjected to consecutive compression-decompression cycles, deforming elastically in all the applied range of deformations. While the overall mechanical response remained almost unchanged varying polymer concentration and ionic cross-linker concentration and nature, the Young's modulus E appeared significantly affected by the applied gelling conditions (E ? 4-20 kPa). As a result of the higher complexity of the extracellular biopolymeric matrix, higher driving forces (sEPS and M2+ concentrations) were needed to form stable and stiff hydrogels with respect to the studied model biopolymers: the establishment of an extended 3D network started for sEPS concentrations around 2.5 wt% (Ca2+ >= 0.1 M). Oscillatory shear ex-periments confirmed that sEPS were able to form hydrogels with solid-like mechanical properties at 1-10 wt% sEPS concentrations. Overall, the optimization of the gelling methods performed might help to overcome many bottlenecks characterizing this research area. The feasibility of forming sEPS hydrogels with mechanical prop-erties comparable to other biopolymer-based systems currently applied for commercial purposes led to an awareness of the potential application and might open new valorisation scenarios able to contribute to a more bio-based and circular economy. |
| Author Keywords |
Extracellular polymeric substances; Aerobic granular waste sludge; Resource recovery; Hydrogel; Methodology; Rheology |
| Index Keywords |
Index Keywords |
| Document Type |
Other |
| Open Access |
Open Access |
| Source |
Science Citation Index Expanded (SCI-EXPANDED) |
| EID |
WOS:000861356500012 |
| WoS Category |
Engineering, Environmental; Engineering, Chemical; Water Resources |
| Research Area |
Engineering; Water Resources |
| PDF |
http://manuscript.elsevier.com/S2214714422005207/pdf/S2214714422005207.pdf
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