11
electrode line with lotus plug separately insert into the electrolytic electrode
interface (Figure 4-1 7) and the measuring electrode interface (Figure 4-1, 8).
V
．
Working principle
Reagent solution is made up of dominant iodine, pyridine with sulfur dioxide
and methanol. Carl, -- Hugh reagent with water reaction principle is: based on
water, the Iodine is restituted by sulfur dioxide; in the presence of pyridine and
methanol, generate hydroiodic acid pyridine and methyl hydrogen sulfate.
Reaction is:
H20+I2+SO2+3C5H5N → 2C5H5N·HI+C5H5N·SO3 …………(1)
C5H5N·SO3+CH3OH → C5H5N·HSO4CH3 ……………… (2)
In the process of electrolysis, the electrode reaction is as follows:
Anode: 2I- - 2e
→
I2 ……………………………………………..(3)
Cathode: 2H+ + 2e
→
H2
↑
…………………………………….…(4)
Iodine (produced by anode) reacts with water to produce hydroiodic acid, until
all the water reacted completely; the reaction end is instructed by a pair of
detection unit which composed of platinum electrodes. Based on Faraday's
law of electrolysis, number of molecules of iodine in the reaction is equal to
number of molecules of water, and it has a proportional relationship with
charge. The equation of water and charge as follows:
W=Q/10.722 ……………………………………………
（
5
）
Wherein:
W --
Moisture content in the sample
Unit: MCG
Q --
Electrolytic power
Unit: Milli-Coulomb
VI. Menu and key operation instructions
Instrument uses a large-screen LCD display, with touch keys, key functions
defined; users learn to use the instrument easier.
Instrument with five menus
