The effect of membrane on the alkaline water production

Abstract

The alkaline ionized water (AIW) produced by the electrolysis process has growing demand due to several health benefits in humans as it hinders the oxidation process caused by free radicals. A batch-mode membrane-aided ionizer is developed in the current research study to produce AIW. Electrodes and cation exchange membrane are the major parts of the device, and the selective penetration of mineral cations into the cathode chamber is governed by the membrane, which further enhances the electrolysis at the cathode to produce more hydroxyl ions, hydrogen, and active hydrogen in the cathode chamber. The produced hydroxyl ions increase the alkalinity of water. Furthermore, the membrane avoids the direct intermixing of the water and gases in between electrode chambers. Four different membranes such as polyvinylidene fluoride (PVDF), cellulose filter paper (CFP), polyethersulfone (PES), and polytetrafluoroethylene (PTFE), were characterized and used in batch ionizer for selective penetration of mineral cations into AIW, and the ionizer performance is investigated against a control experiment without using a membrane. In PVDF and CFP membranes, the pH values were increased and reached the desired 9.5 pH level in 7.2 and 6.4 minutes respectively. However, PES PTFE and control did not achieve desired 9.5 pH. CFP might reach the 9.5 pH level in a short time due to its high ion conductivity (3.8×10-3 S cm-1) than PVDF (9.1×10-5 S cm-1) and larger pore size (~8 µm) than the other membrane types (~0.45 µm). The durability and chemical/physical stability of CFP are lower than PVDF. Furthermore, the membrane is essential for generating AIW without intermixing the water in between the cathode and anode chamber. As a result of that, the present study concluded PVDF is found to be a highly suitable and the best membrane for the proper functioning of the ionizer to produce mineral and antioxidant-enriched AIW.

Full text

ISSN/ISBN ***-****
Young Scientists’ Conference Multidisciplinary Research (YSCMR)-2022
Young Scientists’ Association, National Institute of Fundamental Studies, Sri Lanka
10th of November 2022
Paper ID: CMT-033
The effect of membrane on the alkaline water production
H.M.B.N. Wickramasooriya1*, M.D.Y. Milani2, A.M.K.L. Abeykoon2, R.C.W.
Arachchige2, H.M.B.I. Gunathilaka 2
1Uva Wellassa University, Badulla, Sri Lanka
2Industrial Technology Institute, Colombo, Sri Lanka
*wickramasooriyabhagya96@gmail.com
The alkaline ionized water (AIW) produced by the electrolysis process has growing
demand due to several health benefits in humans as it hinders the oxidation process
caused by free radicals. A batch-mode membrane-aided ionizer is developed in the
current research study to produce AIW. Electrodes and cation exchange membrane
are the major parts of the device, and the selective penetration of mineral cations into
the cathode chamber is governed by the membrane, which further enhances the
electrolysis at the cathode to produce more hydroxyl ions, hydrogen, and active
hydrogen in the cathode chamber. The produced hydroxyl ions increase the alkalinity
of water. Furthermore, the membrane avoids the direct intermixing of the water and
gases in between electrode chambers. Four different membranes such as
polyvinylidene fluoride (PVDF), cellulose filter paper (CFP), polyethersulfone (PES),
and polytetrafluoroethylene (PTFE), were characterized and used in batch ionizer for
selective penetration of mineral cations into AIW, and the ionizer performance is
investigated against a control experiment without using a membrane. In PVDF and
CFP membranes, the pH values were increased and reached the desired 9.5 pH level
in 7.2 and 6.4 minutes respectively. However, PES PTFE and control did not achieve
desired 9.5 pH. CFP might reach the 9.5 pH level in a short time due to its high ion
conductivity (3.8×10-3 S cm-1) than PVDF (9.1×10-5 S cm-1) and larger pore size (~8
µm) than the other membrane types (~0.45 µm). The durability and chemical/physical
stability of CFP are lower than PVDF. Furthermore, the membrane is essential for
generating AIW without intermixing the water in between the cathode and anode
chamber. As a result of that, the present study concluded PVDF is found to be a
highly suitable and the best membrane for the proper functioning of the ionizer to
produce mineral and antioxidant-enriched AIW.
Keywords: electrodes, ionizer, penetration