Using microwaves to accelerate ageing of an ultrafiltration PES membrane by NaOCl to obtain a similar ageing state to that for membranes working at the industrial scale
Résumé
Looking for a lab. scale protocol that leads to aged membranes that could be representative of the aged state obtained at the industrial scale, this paper proposes a systematic study of the degrdn. of a polyethersulfone (PES)/ polyvinylpyrrolidone (PVP) flat membrane by sodium hypochlorite. Different protocols are compared: ageing by immersion in static conditions with or without the coupling of applied microwaves as well as in dynamic conditions, namely directly on an ultrafiltration (UF) pilot. Regardless of the protocol, the physico-chem. evolution of the pristine membrane always highlights the progressive removal of PVP and slow degrdn. of the PES matrix itself. The use of microwaves appears a very interesting way to significantly decrease the duration of the treatment required to damage a membrane close to the aged state at the industrial scale. Nevertheless, some limitations are also evident thanks to UF behavior in terms of both water flux and protein filtration.