Enhanced Permeability and Removal Efficiency for Phenol and Perfluorooctane Sulphonate by a Multifunctional CNT/Al2O3 Membrane with Electrochemical Assistance

Membrane separation is recognized to be a promising technology for addressing water crisis. Unfortunately, the emergence of membrane fouling and low removal efficiency makes it unattractive for practical application. Herein, an electrochemical multifunctional CNT/Al2O3 membrane was designed coupled multiple electrochemical functions with pore sieving, which could maintain high permeability and achieve good removal efficiency simultaneously, even for those molecules with size smaller than pore size. The multifunctional CNT/Al2O3 membrane possessing a pore size of 140 nm and pure water flux of 869.6 L · m-2 · h-1 · bar-1 was prepared. The results show that the multifunctional CNT/Al2O3 membrane exhibited a good anti-fouling properties for both bio-fouling and chemical fouling under electrochemical assistance with a permeability 3.6 and 1.5 times higher than those of CNT/Al2O3 membrane alone for the treatment of E. coli and humic acid, respectively. In addition, the CNT/Al2O3 membrane with electrochemical assistance also shows a high removal efficiency for the treatment of perfluorooctane sulphonate (PFOS) and phenol whose sizes are smaller than pore size. As for the treatment of surface water, it also presented a good performance. Finally, the regeneration of the membrane was investigated and the fouled membrane was reused through an electrochemical assisted back-wash method.

A Study on Microturning with Electrochemical Assistance of the Cutting Process

The paper investigated an electrochemically-assisted microturning process. Depending on the variant of electrochemical assistance, material can be removed with simultaneous electrochemical and mechanical action or electrochemical assistance can change the conditions of the cutting by changing the mechanical properties of the machined material. The experimental part includes discussion of the study methodology and a comparison of straight turning results in the case of machining 1.4301 stainless steel with and without electrochemical assistance. Based on this study, we can confirm that electrochemical assistance brings significant benefits in both variants, especially when the depth-of-cut is in the range of 1 µm.

Enhancement of the Donnan effect through capacitive ion increase using an electroconductive rGO-CNT nanofiltration membrane

Enhanced Donnan repulsion through increase in capacitive ions contributes to the remarkable salt rejection ability of the GCM under electrochemical assistance.