Factors affecting the Faradaic efficiency of Fe(0) electrocoagulation

Abstract

(0) (0) (0) oxidation and O 2 evolution in the EC system. These molar ratios were supported by experiments in synthetic groundwater solutions. We also found that the E A vs i curves for solutions with poor Faradaic efficiency overlapped but were situated 2-4 V vs Ag/AgCl higher than those of solutions with high Faradaic efficiency. Therefore, the position of the E A vs i curve, rather than the E A alone, can be used to determine unambiguously the reaction occurring on the Fe(0) anode during EC treatment.

Iron Transformation and Its Role in Phosphorus Immobilization in a UCT-MBR with Vivianite Formation Enhancement

“…The size of the vivianite crystals in the sludge ranged from 50 to 100 μm, with the shape and transparency suggesting that crystal growth was significant rather than simple precipitation that produces amorphous aggregates (Figure ). In the SEM image (Figure S3), well-ordered crystals growing from approximately the same origin but in all three crystallographic directions were observed in the sludge sampled from the vUCT-MBR, with the resulting crystal morphology similar to that of natural vivianite . At the edges of the crystals, screw dislocations, where spiral growth (BCF growth) commenced, were clearly seen.…”

Enzyme-Assisted Microbial Electrosynthesis of Poly(3-hydroxybutyrate) via CO2 Bioreduction by Engineered Ralstonia eutropha

“…As a result, 0.78 ± 0.03 mM NAD + was reduced within 8 h in the presence of NR, which proved that NR was an efficient electron mediator for NADH regeneration, while Rh achieved 0.59 ± 0.01 mM NADH regeneration at 8 h and riboflavin was unable to regenerate NADH due to its redox potential (−0.4 V vs Ag/AgCl) being higher than that of the NAD + /NADH (−0.52 V vs Ag/AgCl). The Faradaic efficiency of the NADH formation could be calculated by eq : where n is the amount of product (mol), z is the number of transferred electrons ( z = 2 for NADH formation from NAD + ), F is the Faraday constant (96485 C/mol), i is the current (A), and t is the time (s). Thus, according to Figure S3 and eq , the Faradaic efficiencies of NADH regeneration mediated by the shuttle NR and Rh complex were 45.0 ± 1.2% and 34.8 ± 0.4%, respectively.…”

Enhanced electrocoagulation process for natural organic matter removal from surface drinking water sources: coagulant dose control & organic matter characteristics

“…Using these Al EC doses determined for each experiment and using the Faraday constant (i.e., ∼96 500 C per eq., representing the amount of electric charge (Q) as coulombs (C) carried by one mole of electrons or an equivalent of any electro-active chemical species in electrochemical reactions [like Al 3+ in the En-EC process]), the required Q (C) to achieve the selected Al EC dose through the En-EC process can be then calculated (for example, to release each 1 mg L −1 Al 3+ dose, we needed to apply 10.7 C L −1 electricity on the electrodes). 33 From the Q (C) values determined to achieve the selected Al EC dose for each experiment, the EC stage (stage 1) process time can be calculated using the formula, Q (C) = I EC (amperes) × t (s) (for example, in the case of 10.7 C L −1 and for a two litre jar experiment, we need an ∼214 s EC time if the I EC is maintained at 100 mA). 33 The impact of I EC on the En-EC process was investigated over the range of 25 to 750 mA with the Al EC and pH EC maintained under constant conditions.…”