Screen Analysis Method of Cellulose Ether
Scope
This method determines the particle size of products of cellulose ether by sieving material through sieve screens with mesh sizes from 40-325
Principle
cellulose ether is sieved through standard sieve screens using an air-jet sieve. The weight of material retained on a sieve screen is measured and used to calculate
the weight percent of material passed through the sieve screen
Apparatus
- Air-jet sieve: Hosokawa Micron Air Jet Sieve, available from Hosokawa Micron Powder Systems or equivalent AIR-200 Air Jet Sieve
Screen Analysis Method of Cellulose Ether-515pic
AIR-200 Air Jet Sieve-515pic
Air jet sieving machine-515pic-336pic
- Sieve screens and gasket: U.S. standard stainless steel screens, 40, 70, 100, 140, 230, and 325 mesh, available from Hosokawa Micron Powder Systems
- Sieve screen lid: Plexiglas lid, available from Hosokawa Micron Powder Systems, or equivalent AIR-200 Air Jet Sieve
- Balance: Mettler PC440, available from VWR International, 1310 Goshen Parkway West Chester, PA 19380, or equivalent AIR-200 Air Jet Sieve
- Talcum powder: with no particles greater in size than can pass through the finest-mesh sieve screen used in the analysis, Fisher Lab Grade, catalog number T4-10, available from Fisher Scientific, or equivalent AIR-200 Air Jet Sieve
Procedure
- Locate all necessary sieve screen mesh sizes required for the sample analysis. Inspect each screen for tears. Discard any structurally-compromised screens and replace with new screens.
- Weigh one of the clean sieve screens, with gasket, and record the weight to the nearest 0.01g. Place the sieve screen on to the air-jet sieve, sliding the gasket down to seal against the air-jet sieve.
- Weigh 20.0 ± 0.1 g of sample into a metal bowl and record the weight to the nearest 0.01 g.
- Add 2.0 ± 0.5 g of talcum powder (Section 5.5) to the metal bowl and record the weight to the nearest 0.01g.
- Mix the talcum powder thoroughly with the sample using a metal spoon .
Note: The talcum powder will minimize the build-up of a static charge during the vacuum sieving process (Section 6.7). The talcum powder will be removed by the vacuum and will not affect the final sample weight retained on the sieve screen. Use of talcum powder is not needed for the analysis of granular samples with bulk density <250g/L.
- Transfer the contents of the metal bowl to the sieve screen. Place lid on the sieve screen.
- Set the air-jet timer to 360 sec. and press start to sieve the sample for 6 minutes at a vacuum of 300-mm (12.3-inches) water.
- After sieving stops, remove the sieve screen from the air-jet sieve. Remove the lid and reweigh the sieve screen with gasket. Record the weight to the nearest 0.01 g.
- Repeat for each required sieve screen .
- Clean any remaining sample from the sieve screens and lid.
Calculation
Calculate the weight percent of sample material passed through a sieve screen
Air jet sieve https://www.aimsizer.com