horiba HU-200TB-W SS-120-W, Инструкция по эксплуатации

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Data
80

Kaolin standard solution
Tip
Immediately after Kaolin is dissolved with water, the Kaolin particles contain air and the dispersion
status is imperfect, and therefore, turbidity is not stable. For this reason, prepare a highly
concentrated solution in advance, and leave it in water to help assimilation.

Items to be prepared

Reagent: Kaolin

Balance: One that can measure 100 g with an accuracy of 0.01 g

500 mL beaker

1000 mL measuring flask

Magnetic stirrer

Deionized water: Highly filtered ion-exchanged water

Preparation procedure
1.
Add deionized water to 10 g of Kaolin to make 1 L in total and prepare 10000 mg/L
of Kaolin solution (Kaolin of 10000 degrees)
This will be solution A.
2.
Leave solution A for at least a day.
Tip
It is recommended that you add 1 g of dispersant, sodium pyrophosphate, to solution A. Due to the
effect of the dispersant, the Kaolin powder is dispersed to form a solution that is less likely to settle.

Span solution
After collecting 10 mL of well-mixed solution A, add deionized water to make 1 L in total to
prepare 100 mg/L (100 degrees) of span solution.
Or, after collecting 1 mL of solution A, add deionized water to make 1 L in total to prepare 10
mg/L (10 degrees) of span solution.
According to this procedure, adjust the span solution to an arbitrary turbidity (concentration)
by diluting solution A.

About dispersant
When 0.1

of dispersant is added to a highly concentrated Kaolin standard solution (10000
mg/L or more), it becomes easier to handle Kaolin standard solutions. However, the turbidity
properties may change due to the effect of the dispersant. When dispersant is added to
Kaolin, the Kaolin particles are finely dispersed. Due to this, the particles increase from the
Mie scattering region to the Rayleigh scattering region, and the scattered light decreases. As
a result, the turbidity might change to a slightly lower level. However, when a highly
concentrated Kaolin solution is handled without adding dispersant, it settles quickly, and
therefore it is difficult to perform the fixed quantity procedure. In this respect, the addition of
dispersant is effective.