TY - JOUR
T1 - Ranking nano-enabled hybrid media for simultaneous removal of contaminants with different chemistries
T2 - Pseudo-equilibrium sorption tests versus column tests
AU - Custodio, Tomas
AU - Garcia, Jose
AU - Markovski, Jasmina
AU - McKay Gifford, James
AU - Hristovski, Kiril
AU - Olson, Larry
N1 - Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2017/12/15
Y1 - 2017/12/15
N2 - The underlying hypothesis of this study was that pseudo-equilibrium and column testing conditions would provide the same sorbent ranking trends although the values of sorbents' performance descriptors (e.g. sorption capacity) may vary because of different kinetics and competition effects induced by the two testing approaches. To address this hypothesis, nano-enabled hybrid media were fabricated and its removal performances were assessed for two model contaminants under multi-point batch pseudo-equilibrium and continuous-flow conditions. Calculation of simultaneous removal capacity indices (SRC) demonstrated that the more resource demanding continuous-flow tests are able to generate the same performance rankings as the ones obtained by conducing the simpler pseudo-equilibrium tests. Furthermore, continuous overlap between the 98% confidence boundaries for each SRC index trend, not only validated the hypothesis that both testing conditions provide the same ranking trends, but also pointed that SRC indices are statistically the same for each media, regardless of employed method. In scenarios where rapid screening of new media is required to obtain the best performing synthesis formulation, use of pseudo-equilibrium tests proved to be reliable. Considering that kinetics induced effects on sorption capacity must not be neglected, more resource demanding column test could be conducted only with the top performing media that exhibit the highest sorption capacity.
AB - The underlying hypothesis of this study was that pseudo-equilibrium and column testing conditions would provide the same sorbent ranking trends although the values of sorbents' performance descriptors (e.g. sorption capacity) may vary because of different kinetics and competition effects induced by the two testing approaches. To address this hypothesis, nano-enabled hybrid media were fabricated and its removal performances were assessed for two model contaminants under multi-point batch pseudo-equilibrium and continuous-flow conditions. Calculation of simultaneous removal capacity indices (SRC) demonstrated that the more resource demanding continuous-flow tests are able to generate the same performance rankings as the ones obtained by conducing the simpler pseudo-equilibrium tests. Furthermore, continuous overlap between the 98% confidence boundaries for each SRC index trend, not only validated the hypothesis that both testing conditions provide the same ranking trends, but also pointed that SRC indices are statistically the same for each media, regardless of employed method. In scenarios where rapid screening of new media is required to obtain the best performing synthesis formulation, use of pseudo-equilibrium tests proved to be reliable. Considering that kinetics induced effects on sorption capacity must not be neglected, more resource demanding column test could be conducted only with the top performing media that exhibit the highest sorption capacity.
KW - Arsenic
KW - Granular activated carbon
KW - Media screening
KW - Methyl Orange
KW - Sorption
KW - Titanium dioxide
UR - http://www.scopus.com/inward/record.url?scp=85021261956&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85021261956&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2017.06.104
DO - 10.1016/j.scitotenv.2017.06.104
M3 - Article
C2 - 28666171
AN - SCOPUS:85021261956
SN - 0048-9697
VL - 605-606
SP - 166
EP - 171
JO - Science of the Total Environment
JF - Science of the Total Environment
ER -