An experimental investigation into the pre-treatment of synthetic membranes using sodium hydroxide solutions

• Published in: Journal of food engineering Vol. 105; no. 1; pp. 128 - 137
• Main Authors: Jones, Sarah A., Bird, Michael R., Pihlajamäki, Arto
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.07.2011; Elsevier
• Subjects: artificial membranes; Biological and medical sciences; brix; cleaning; Conditioning; Cut off; Drying; feeds; filtration; Fluoropolymers; Food engineering; Food industries; Foods; fouling; Fundamental and applied biological sciences. Psychology; General aspects; Membrane pre-treatment; Membranes; Molasses; molecular weight; Polysulphone; Preconditioning; Sodium hydroxide; Spent sulphite liquor; Sugar industries; Zeta potential; Molasses; Membrane pre-treatment; Spent sulphite liquor; Zeta potential; Membrane; Pretreatment; Solution; Sodium hydroxide
• ISSN: 0260-8774; 1873-5770
• DOI: 10.1016/j.jfoodeng.2011.02.015

In this paper the effect of two pre-treatment methods are compared experimentally for the filtration of (i) a spent sulphite liquor (17.8 wt.% dry solids) using a 20 kg mol −1 molar mass cut off (MMCO) fluoropolymer membrane and (ii) a molasses solution (45° Brix) using a polysulphone (Ps f) membrane (1.5 μm pore size). Both feeds are industrially relevant, and subject to severe fouling issues when membranes are used in their subsequent processing. The pre-treatment methods evaluated were: (i) conditioning with water at 60 °C only [Protocol 1], and (ii) conditioning with water at 60 °C followed by cleaning with 0.5 wt.% NaOH [Protocol 2]. Results are presented that confirm the benefits of sodium hydroxide preconditioning upon performance, supporting the suggestion by some membrane manufacturers that this step be included as part of the pre-treatment protocol.