Brunauer-Emmett-Teller analysis – a suitable method for membrane fouling in lignocellulosic biorefineries?

Description

The pulping industry is one of the most important industrial sectors in the Nordic countries and an important industrial sector worldwide. The process and wastewater in the pulping industry contain often valuable and underutilized compounds such as hemicelluloses, lignin and extractives. In the concept of lignocellulosic biorefineries, these compounds could be fully utilised and refined to biochemicals, biofuels and advanced materials.

Efficient recovery of the often diluted wood compounds from aqueous streams in the pulping industry requires energy- and cost-efficient separation/concentration processes. Ultrafiltration (UF) has been proven to be a suitable technology for this task. However, the most common UF membrane materials – polysulfone (PS) and polyethersulfone (PES) - are prone to the adsorption of wood chemicals leading to membrane fouling. Attempts to prevent and minimize membrane fouling requires a deep understanding on the fouling mechanisms and their relative effects.

In this study, Brunauer-Emmett-Teller (BET) nitrogen adsorption/desorption analysis was applied to get new insights into pore-level membrane fouling phenomena occurring during UF of process water from lignocellulosic biorefineries. The fouling of commercial PS and PES membranes by black liquor, thermomechanical pulping process water and pressurized hot-water extract was investigated with BET analysis and infrared spectroscopy. Particular emphasis was given to the applicability of BET analysis for membrane fouling characterization.

The presentation will show that BET analysis is a suitable method to determine the influence of fouling on the inner structure of a membrane. It was possible to observe changes in the cumulative pore volumes and pore areas in the mesopore region. This information, together with data from infrared spectroscopy, provides new insights on the structure of the fouling layer and the chemical nature of the foulants. The gained knowledge deepens the understanding of membrane fouling and will support the further dissemination of membrane processes in lignocellulosic biorefineries.

Period	2020 Dec 7 → 2020 Dec 11
Event title	12th International Congress on Membranes and Membrane Processes
Event type	Conference
Location	London, United KingdomShow on map
Degree of Recognition	International