Hach DR/850 - Page 24

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CHEMICAL ANALYSIS INFORMATION, continued
REQUIRED APPARATUS FOR VACUUM FILTRATION
Description Unit Cat. No
.
Filter Discs, glass 47 mm, 1.5 µm ........................................................ 100/pkg............2530-00
Filter Holder, membrane.............................................................................each..........13529-00
Flask, filter, 500 mL....................................................................................each..............546-49
Pump, vacuum, hand operated....................................................................each..........14283-00
OR
Pump, vacuum, portable, 115 V..................................................................each..........14697-00
Pump, vacuum, portable, 230 V .................................................................each..........14697-02
Several procedures in this manual use gravity filtration. The only labware
required is filter paper, a conical funnel and a receiving vessel. This
labware is included under Optional Apparatus at the end of a procedure.
Gravity filtration is better for retaining fine particles. For faster filtering,
add solution until the filter paper cone is three-fourths filled. Never fill
the cone completely. Gravity filter (see Figure 2) as follows:
1. Place a filter paper into the funnel.
2. Wet the filter with deionized water to ensure adhesion to the funnel.
Allow all the deionized water to drain.
3. Place the funnel into an erlenmeyer flask or graduated cylinder.
4. Pour the sample into the funnel.
Figure 2 Gravity Filtration
REQUIRED APPARATUS FOR GRAVITY FILTRATION
Description Unit Cat No.
Cylinder, graduated, 100 mL ......................................................................each..............508-42
Funnel, poly, 65 mm ...................................................................................each............1083-67
Filter Paper, 12.5 cm...................................................................................each............1894-57
Flask, erlenmeyer, 125 mL .........................................................................each..............505-43