Hoshizaki ROX-20TB2-U service manual

Salt water contains four kinds of ions; sodium ions (Na+), chlorine ions (Cl-), hydrogen ions (H+) and hydroxide ions (OH-).

NaCl + H2O	→	Na+ + Cl- + H+ + OH-
(Mix water and salt)		Salt water (4 kinds of ions)

When two electrodes are inserted into salt water and voltage is applied:

Negative ions (Cl-) are drawn to the anode, and

Positive ions (Na+) are drawn to the cathode.

At the anode, hydrogen chloride (HCl) and hypochlorous acid (HOCl) are generated.

2Cl- + H2O → HCl + HOCl + 2e-

Electrons (2e-) are emitted to the anode, which means the acidic water (HCl + HOCl) causes

oxidization. [As electrons are emitted, the oxidization/reduction potential becomes positive (+mV).]

Chlorine ions also emit electrons and become chlorine gas (Cl2).

2Cl- →	Cl2 + 2e-
	(Cl2 = chlorine gas)

At the cathode, sodium hydroxide (NaOH) and hydrogen gas (H2) are generated.

Na+ + H2O + H+ + 2e- → NaOH + H2

Electrons (2e-) are received from the cathode, which means the alkali water (NaOH) causes reduction. [As electrons are received, the oxidization/reduction potential becomes negative (-mV).]

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