FCCV标准-Talc滑石粉.pdf

464/Talc/ Monographs
FCCV
AppendDetermine as directed in Mercury under Colors, mL of 2 N sulfuric acid to 10 mL of the filurate, evaporat
Merc
Appendix IIIc
to dryness, and ignite to constant weight. The weight of the
Sulfates Determine as directed in Sodium Sulfate under Col- residue does not exceed 12.5 mg
ors, Appendix IIIC
Uncombined Intermediates and Products of Side Reac-
Sample Solution for th
Solution for the Det
rmination of Arseni
ic
Intermediates and Products of Side Reactions under Colors, a reflux condenser to the
eat on a steam bath
Preparation: Transfer 0.25 g of sample, accurately weighed,
for 30 min, cool, and let the undissolved material settle.
Decant the supernatant liquid through Whatman No. 3
into a 100-mL volumetric flask. Dissolve in and dilute to
Daper
filter paper, c
_volumetric
volume with 0. M disodium tetraborate (Na B40).
Water-Insoluble Matter Determine as directed in Water-
flask, retaining as much as possible of the insoluble
Insoluble Matter under Colors, Appendix IIIC
material in the beaker. Wash the slurry and beaker
with three 10-mL portions of hot water, decanting each
Packaging and Storage Store in well-closed containers
washing through the filter into the flask. Finally, wash
the filter paper with 15 mL of hot water, cool the filtrate
to room temperature, dilute to volume with water,
and mix.
Talc
Arsenic Determine as directed under Arsenic Limit Test,
Appendix IIIB, using a
e Sample Solution
(above).
ins:55)
CAS: [14807-96-61 Free Alkali (as NaOH) Add 2 drops of phenolphthalein TS
to 20 mL of the diluted filtrate prepared in the test for Soluble
Salts (below), representing 1 g of sample. If a pink color
DESCRIPTION
appears, not more
).1 N hydrochloric acid is
required to discharge
Talc occurs as a white to gray-white, unctuous powder. It is Lead Deterr
ected under L.ead Limit Test, Appen-
a naturally occurring form of hydrous magnesium silicate dix IlIB, using a
ion of the Sample Solution
containing varying proportions of such associated minerals (above), and 5 ug of
as alpha-quart, calcite, chlorite, dolomite, kaolin, magnesite,
Loss on Drying D
der Loss on Dry-
and phlogopite. Talc derived from deposits that are known ing, Appendix
to contain associated asbestos is not food grade It is insoluble Loss on Ignition
f sample in
in water and in solutions of alkali hydroxides but is slightly a tared platinum cru
ally apply
soluble in dilute mineral acids.
heat gradually, and
Soluble Salts Boil
ith 150 mL of water
Function Anticaking agent; coating agent; lubricating and for 15 min. Cool
release agent; surface-finishing agent; texturizing agent.
the original
water to restore
and filter until clear
water to 75 mL of the
REQUIREMENTS
clear filtrate. Evaporate 5
his solution, representing
Identification
2.5 g of sample, in a tared platinum dish on a steam bath to
A. The X-ray diffraction pattern of a random powder sample
dryness, and ignite ge
to constant weight. The weight of
exhibits intense reflections at the following d values: 9.34 A
the re