GB/T 26900-2011Bamboo charcoal for air-purification (English PDF)

3.1 Appearance. black, odorless, tasteless, amorphous solid.

4.3 Determination of volatile matter content

4.3.1 Method summary

At the temperature of (850±20)°C, test sample with certain mass is heated for 7min with

isolation from the air. The percentage OF lost mass TO the original test sample's mass is

the volatile matter content. If obvious sparks are generated in the experiment, the

experiment shall be redone.

4.3.2 Instruments

4.3.2.1 Porcelain crucible. Height. 40mm; diameter of upper mouth. 30mm; bottom outer

diameter. 18mm; cover outer diameter. 35mm; groove outer diameter. 29mm; external

groove depth. 4mm.

4.3.2.2 High temperature electric furnace. Provided with temperature control device that

can maintain at the temperature of (850±20)°C.

4.3.2.3 Crucible holder. Made of nichrome wire. Crucible's size does not exceed the limit

of constant temperature region in the high temperature furnace. And MAKE the bottom of

the crucible on the shelf of the crucible to be 10mm - 15mm from the bottom of the

furnace.

4.3.2.4 Analytical balance. with sensitivity of 0.1mg.

4.3.2.5 Stopwatch or time clock.

4.3.2.6 Dryer. with desiccant (Not-deliquescent bulk-shape calcium chloride or silica gel)

in it.

4.3.3 Operating methods

WEIGH 1g (accurate to 0.1mg) of test sample that has been crushed and gone through

0.25mm (60-mesh) sieve. PLACE in the porcelain crucible that has been burned to

constant weight at (850±20)°C. COVER the crucible. Gently SHAKE to make the test

sample spread out. PLACE it on the crucible shelf. Then, quickly PLACE it into the high

temperature electric furnace that has been pre-heated to 850°C. The crucible locates

above or below the measurement point of the thermocouple. CONTINUE to heat it for

7min. The temperature of furnace drops at the beginning, but shall be restored to

(850±20)°C within 3min. If there are obvious sparks, it shall be redone.

Finally, TAKE the crucible out and PLACE it on the porcelain plate. COOL it in the air for

5min. PLACE it in a dryer and COOL it to the room temperature. And WEIGH it.

4.3.4 Result calculation

CALCULATE the volatile matter content determination results of bamboo charcoal for

air-purification by formula (3).

Where.

V — Volatile matter content of test sample, %;

m1 — Mass of test sample, in unit of gram (g);

m2 — Mass of test sample after heating, in unit of gram (g);

4.3.5 Allowable errors

The errors of 2 parallel determination results of volatile matters shall not exceed 0.5%.

4.4 Determination of the content of fixed carbon

4.4.1 Method summary

CALCULATE the fixed carbon content BY the mass of dried bamboo charcoal MINUS its

ash content and volatile matter content.

4.4.2 Instruments

4.4.2.1 The ash content test instrument, same as 4.2.2.

4.4.2.2 The volatile matter content test instrument, same as 4.3.2.

4.4.3 Operating methods

4.4.3.1 CRUSH the analysis test sample until all can go through the 0.25mm-sieve (60

meshes). DRY to constant weight at the temperature of 102°C~105°C. The mass of the

test sample shall not be less than 30g, for the use of testing the ash content and volatile

matters.

4.4.3.2 The operating method of determination of ash content is shown in 4.2.3.

4.4.3.3 The operating method of determination of volatile matter content is shown in

4.3.3.

4.4.4 Result calculation

CALCULATE the fixed carbon content determination results of bamboo charcoal for

air-purification by formula (4).

4.5.3.2 Electrothermal constant-temperature drying oven. with automatic temperature

control device, and with blower or natural ventilation device.

4.5.3.3 Climate box. 1m3.

4.5.3.4 Weighing bottle. 60mm × 30mm.

4.5.3.5 Analytical balance. with sensitivity of 0.1mg.

4.5.3.6 Dryer. with desiccant (Not-deliquescent bulk-shape calcium chloride or silica gel)

in it.

4.5.4 Operating methods

WEIGH 1g (accurate to 0.1mg) of test sample that has been crushed and gone through

0.25mm (60-mesh) sieve. PLACE in the weighing bottle that has been constant-eight in

advance. The thickness of the test sample in the bottom of the weighing bottle shall be

well-distributed.

Then PLACE the weighing bottle filled with formaldehyde to the specified location in the

bottom of adsorption instrument. The volatile capacity of formaldehyde shall be larger

than the adsorption capacity of the test sample. Meanwhile, PLACE the weighing bottle

filled with test sample to the grating of adsorption instrument. ABSORB for 24h in the

climate box at the constant temperature of 20°C. WAIT to be tested. Blank test is

conducted simultaneously.

4.5.5 Result calculation

4.5.5.1 The formaldehyde adsorption rate can be expressed by %, and calculated by

formula (5).

Where.

X — Formaldehyde adsorption rate of bamboo charcoal, %;

m1 — Mass of test samples before adsorption AND weighing bottle, in unit of gram (g);

m2 — Mass of test samples after the adsorption of 24h AND weighing bottle, in unit of

Where.

B — TVOC adsorption rate of bamboo charcoal, in unit of milligram per gram (mg/g);

X — TVOC adsorption rate of the bamboo charcoal, %.

4.7.6 Allowable errors

The errors of 2 parallel determination results of the TVOC adsorption rate shall not exceed

0.3%.

5.1 Inspection classification

5.1.1 Ex-factory insp...

......