TY - JOUR
T1 - Membraneless water filtration using CO2
AU - Shin, Sangwoo
AU - Shardt, Orest
AU - Warren, Patrick B.
AU - Stone, Howard A.
N1 - Publisher Copyright:
© The Author(s) 2017.
PY - 2017
Y1 - 2017
N2 - Water purification technologies such as microfiltration/ultrafiltration and reverse osmosis utilize porous membranes to remove suspended particles and solutes. These membranes, however, cause many drawbacks such as a high pumping cost and a need for periodic replacement due to fouling. Here we show an alternative membraneless method for separating suspended particles by exposing the colloidal suspension to CO2. Dissolution of CO2 into the suspension creates solute gradients that drive phoretic motion of particles. Due to the large diffusion potential generated by the dissociation of carbonic acid, colloidal particles move either away from or towards the gas-liquid interface depending on their surface charge. Using the directed motion of particles induced by exposure to CO2, we demonstrate a scalable, continuous flow, membraneless particle filtration process that exhibits low energy consumption, three orders of magnitude lower than conventional microfiltration/ultrafiltration processes, and is essentially free from fouling.
AB - Water purification technologies such as microfiltration/ultrafiltration and reverse osmosis utilize porous membranes to remove suspended particles and solutes. These membranes, however, cause many drawbacks such as a high pumping cost and a need for periodic replacement due to fouling. Here we show an alternative membraneless method for separating suspended particles by exposing the colloidal suspension to CO2. Dissolution of CO2 into the suspension creates solute gradients that drive phoretic motion of particles. Due to the large diffusion potential generated by the dissociation of carbonic acid, colloidal particles move either away from or towards the gas-liquid interface depending on their surface charge. Using the directed motion of particles induced by exposure to CO2, we demonstrate a scalable, continuous flow, membraneless particle filtration process that exhibits low energy consumption, three orders of magnitude lower than conventional microfiltration/ultrafiltration processes, and is essentially free from fouling.
UR - http://www.scopus.com/inward/record.url?scp=85026828291&partnerID=8YFLogxK
U2 - 10.1038/ncomms15181
DO - 10.1038/ncomms15181
M3 - Article
C2 - 28462929
AN - SCOPUS:85026828291
SN - 2041-1723
VL - 8
SP - 15181
JO - Nature Communications
JF - Nature Communications
M1 - 15181
ER -