The use of carbon flow electrodes has significantly impacted electrochemical energy storage and capacitive deionization (CDI). We here introduce flowable fluidized bed with exceptionally high loading, apply these to water desalination by CDI.

Understanding the salt–water separation mechanisms of reverse osmosis (RO) membranes is critical for further development and optimization RO technology. The solution-diffusion (SD) model widely used to describe water salt transport in RO, but it does not intricate molecules ions through membrane. In this study, we develop an ion referred as solution-friction model, by rigorously considering partitioning interactions among water, ions, Ion membrane described extended Nernst–Planck equation,...

Reverse osmosis (RO) and electrodialysis (ED) are the two most important membrane technologies for water desalination treatment. Their modes of operation transport mechanisms very different, but on a closer look also have many similarities. In this concise version our tutorial review, we describe state-of-the-art theory both processes, focusing simple examples that helpful non-specialist useful classroom teaching. Both processes described by solution (SF) which combines ion across membranes...

Hydrophilic organic micropollutants are commonly detected in source water used for drinking production. Effective technologies to remove these from include adsorption onto granular activated carbon fixed-bed filters. The rate-determining step using is usually the adsorbate diffusion inside porous adsorbent. presence of mesopores can facilitate diffusion, resulting higher rates. We two different types carbon, with and without mesopores, study rate hydrophilic micropollutants. Furthermore,...

In the field of Capacitive Deionization (CDI), it has become a common notion that constant current (CC) operation consumes significantly less energy than voltage (CV). Arguments in support this claim are CC endpoint is reached only at end charging step, and thus average cell during lower voltage, we can recover part invested discharge. Though these arguments correct, present work based on experiments theory, conclude well-defined CDI cycle, does not lead, for case analyze, to general...

Membrane capacitive deionization (MCDI) is a technique for water desalination by adsorbing ions in charged porous electrodes. In the present experimental and theoretical study, we analyze performance, terms of energy consumption, salt rejection recovery, MCDI operated intermittent flow mode. With this mode, recovery increased reducing ratio during regeneration. Both results show that high values can be achieved with lab-scale system feed salinity 40 mM. Importantly, find requirement factor...

Water reuse is one of the possible solutions to prevent depletion freshwater resources; however, it often limited by accumulation specific ions in recirculating water. Ion selective desalination technologies can increase potential for water reuse. Electrodialysis a treatment technology that able selectively remove from In order enhance and further develop selectivity process, fundamental understanding various mechanisms governing multi-ion transport electrodialysis essential. present study,...

We analyze selective removal of anions in electrodialysis (ED) from a multicomponent ion mixture where all ions are monovalent, both experimentally, and by modified theory. The theory makes use the Nernst-Planck equation to describe transport across ion-exchange membranes combination with affinity, which is parameter that accounts for preference membrane materials adsorb one more than another. For NO3- Cl- anions, affinity was measured an adsorption experiment, it found adsorbs...

Electrodialysis is a water desalination technology that enables selective separation of ions, making it promising solution for sustainable reuse. The selectivity the process mainly determined by properties ion exchange membranes can vary depending on composition ions in water, such as uptake and charge density. In this work, we studied adsorption Na

Ion-exchange membranes (IEMs) are essential components of several electrochemical water technologies where they promote the transport certain ionic species over others. A characteristic property IEMs concerns their charge density (ICD) which is a key parameter for modeling ion transport. In literature, significant variations in ICD similar reported. We analyzed sources this and traced those back to content measurement. manuscript, we developed new technique measuring content, i.e., via...

Capacitive deionization (CDI) typically uses one porous carbon electrode that is cation adsorbing and anion adsorbing. In 2016, Smith Dmello proposed an innovative CDI cell design based on two cation-selective electrodes a single anion-selective membrane, thereafter this was experimentally validated by various authors. design, anions pass through the membrane once, desalinated water continuously produced. present work, idea extended, it shown also choice for electrodes, in combination with...

Activated carbon is the most common electrode material used in electrosorption processes such as water desalination with capacitive deionization (CDI). CDI a cyclic process to remove ions from aqueous solutions by transferring charge one another. When multiple salts are present solution, removal of each ionic species can be different, resulting selective ion separations. This selectivity result combined effects, differences hydrated size and valence ions. In work, we study salt mixtures two...

Capacitive deionization (CDI) is a desalination technique that can be applied for the separation of target ions from water streams. For instance, mono- and divalent cation selectivities were studied by other research groups in context softening. Another focus on removing Na+ recirculated irrigation (IW) greenhouses, aiming to maintain nutrients. This important as an excess has toxic effects plant growth decreasing uptake In this study, we investigated selective sodium (Na+) magnesium (Mg2+)...

In nanofiltration (NF), solution and membrane chemistry determine the charge density. multi-component electrolytes solutions, it is important to consider interaction between ions NF membranes. For instance, in presence of divalent ions, reversal can take place due counterions with charged functional groups membrane. This paper presents a model based on state-of-the-art mean-field theory that includes effect By using Langmuir equation two parameters, we adsorption (e.g., Ca2+ Mg2+) polyamide...

Bioelectrochemical systems recover valuable components and energy in the form of hydrogen or electricity from aqueous organic streams. We derive a one-dimensional steady-state model for ion transport bioelectrochemical system, with ions subject to diffusional electrical forces. Since most ionic species can undergo acid-base reactions, is combined our infinitely fast equilibrations. The describes current-induced ammonia evaporation recovery at cathode side system that runs on an stream...

Recently we showed that membrane capacitive deionization (MCDI) can be used to capture CO2, but found the performance decreases with decreasing current density. In present study, investigate effect of electrodes and ion exchange membranes by performing experiments two (CO2-MCDI), one (cation or anion membrane), without (CO2-CDI). We find is essential keep high CO2 absorption efficiencies ( [Formula: see text] /ncharge), while efficiency CO2-CDI cell was lower than expected (Λa≈0.5 for...

Membrane capacitive deionization (MCDI) is a water desalination technology employing porous electrodes and ion-exchange membranes. The are cyclically charged to adsorb ions discharged desorb ions. During MCDI operation, difference in pH between feed effluent observed, changing over time, which can cause the precipitation of hardness consequently affect long-term stability These changes be attributed different phenomena, divided into two distinct categories: Faradaic non-Faradaic. In present...

Reverse osmosis (RO) is the most important membrane technology for desalination of water. Measured water and salt fluxes are traditionally analyzed in context solution-diffusion (SD) model which leads to a permeability, A, B. However, this parametrization flux not correct by RO membranes, because these membranes show markedly different retentions feed concentrations, classical observation literature, effect captured SD model. Thus, traditional permeability B an intrinsic property membranes....

Increasing global water stress motivates a growing interest in seawater desalination by reverse osmosis. Boron is typically weakly removed osmosis membranes at pH, necessitating expensive post-processes such as caustic agent dosing of the permeate followed additional filtration steps. It has been previously demonstrated that membraneless capacitive deionization can enable chemical-free boron removal from permeate, with basic design rules established. However, level electrosorption per cell...