1070-4272/05/7802-0329 + 2005 Pleiades Publishing, Inc.
Russian Journal of Applied Chemistry, Vol. 78, No. 2, 2005, pp. 329!332. Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 2, 2005,
Original Russian Text Copyright + 2005 by Sagdullaev.
AND POLYMERIC MATERIALS
Cleaning of Microfiltration Membranes for Filtration
of Aqueous Extract of Marsh Mallow
B. T. Sagdullaev
Yunusov Institute of Chemistry of Vegetable Compounds, Academy of Sciences of the Republic of Uzbekistan,
Received January 20, 2004
Abstract-Cleaning of a microfiltration membrane was studied using various chemicals. The activation
energy and cleaning constant were estimated for alkaline cleaning.
Baromembrane filtration methods (microfiltration,
ultrafiltration, nanofiltration, and reverse osmosis) are
widely used in processing of synthetic and natural
high-molecular-weight compounds for their concentra-
tion, desalination (removal of low-molecular-weight
compounds from solutions of macromolecules), and
Among the most important problems arising in
using membrane filtration in biotechnology and food
and pharmaceutical industries is that the membrane
throughput decreases in the course of filtration ,
which is caused by such factors as increase in the con-
centration of components retained at the membrane
surface [5, 6] and adsorption of colloids, microor-
ganisms, and organic compounds on the surface and
in the pores of the membrane [6, 7]. Both these factors
reduce the effective pore size, thus increasing the re-
sistance of the membrane to the flux .
The problems arising from membrane fouling start-
ed to be manifested in full measure upon accumula-
tion of data on operation of industrial units . Foul-
ing with organic contaminants plays an especially
significant role in filtration of macromolecular com-
pounds, which can form a gel layer on the membrane
surface . Studies concerned with the problem of
fouling are being conducted in various areas including
development of cleaning methods . Chemical clean-
ing involves treatment of filters with various agents,
allowing regeneration of a membrane without disas-
sembling of a membrane unit (cleaning-in-place) .
To optimize chemical cleaning, specific features of
a given process and the type of the membrane used
should be taken into account.
The goal of this study was to optimize the chemical
cleaning of a membrane contaminated during micro-
filtration of the extract of marsh mallow.
In the study we used an Alpma microfiltration sys-
tem (Germany) (Fig. 1) equipped with two mem-
brane units (Kerasep, France). Each unit consisted
of nine cylindrical membranes fabricated from TiO
with the Al
active layer (nominal pore size
0.2 mm). Membranes of this type are thermally and
chemically resistant over the pH range 1314 at
The water flux across an unused membrane at a trans-
membrane pressure P
= 85 kPa was 1650 l m
and the resistance, R
= 1.96 0 10
Fig. 1. Microfiltration flowsheet.