Determination of activated carbon fiber adsorption capacity for several common organic vapors: applications for respiratory protection

Figures & data

Table 1. ACF media characteristics

Media Name	Precursor	Reported Surface Area (m^2/gram)	Single-layer depth (cm)
ACFF 2000	Rayon	2000	0.30
ACFF 1800	Rayon	1800	0.30
ACFF 1200	PAN	1200	0.25

Table 2. Challenge contaminant properties

Challenge Contaminant	Chemical Class	OSHA PEL	Acute Health Effects
Toluene	Aromatic	200 ppm	Vapors irritate the eyes and upper respiratory tract; exposure can cause dizziness, headache, and neurological impairment
Hexane	Aliphatic	500 ppm	Irritation of respiratory tract, cough, mild depression, cardiac arrhythmias
Methyl Ethyl Ketone	Polar	200 ppm	Vapors irritate the eyes, nose and throat

Figure 1. Simplified experimental set-up.

Figure 2. Plots of 10% toluene breakthrough time in minutes for each ACF media type at successive bed depths. The challenge contaminant was 200 ppm toluene.

Figure 3. Plots of 10% toluene breakthrough time in minutes for each ACF media type at successive bed depths. The challenge contaminant was 200 ppm toluene.

Figure 4. Plots of 10% toluene breakthrough time in minutes for each ACF media type at successive bed depths. The challenge contaminant was 200 ppm toluene.

Figure 5. Plots of 10% MEK breakthrough time in minutes for each ACF media type at successive bed depths. The challenge contaminant was 200 ppm methyl ethyl ketone (MEK).

Figure 6. Plots of 10% MEK breakthrough time in minutes for each ACF media type at successive bed depths. The challenge contaminant was 200 ppm methyl ethyl ketone (MEK).

Figure 7. Plots of 10% MEK breakthrough time in minutes for each ACF media type at successive bed depths. The challenge contaminant was 200 ppm methyl ethyl ketone (MEK).

Figure 8. Plots of 10% hexane breakthrough time in minutes for each ACF media type at successive bed depths. The challenge contaminant was 200 ppm hexane.

Figure 9. Plots of 10% hexane breakthrough time in minutes for each ACF media type at successive bed depths. The challenge contaminant was 200 ppm hexane.

Figure 10. Plots of 10% hexane breakthrough time in minutes for each ACF media type at successive bed depths. The challenge contaminant was 200 ppm hexane.

Table 3. Results of ACF surface area analysis

Parameters	ACFF 1800	ACFF 2000	ACFF 1200
Nominal surface area (m^2/g)	1800	2000	1200
BET Surface Area (m^2/g)	1541.34	1903.55	1205.97
Micropore area (m^2/g)	1056.14	838.89	1015.25
% Micropore by area	68.52	44.06	78.70
Pore Volume (cm^3/g)	0.69	0.90	0.58
Micropore Volume (cm^3/g)	0.41	0.32	0.42
% Micropore by volume (cm^3/g)	59.51	35.71	72.96
Pore Size (nm)	1.80	1.91	1.82

Table 4. Breakthrough experiments with 200 ppm Toluene as challenge contaminant

Adsorbent	Layer	Bed weight (g)	tb10% (min)	Experimental Capacity (mg/g)
ACFF 1200	1	0.167	7.67
	2	0.338	16.83
	3	0.518	25.00	239.26
	4	0.708	30.50
ACFF 1800	1	0.204	10.83
	2	0.390	21.83	344.09
	3	0.591	32.50
	4	0.780	46.50
ACFF 2000	1	0.204	10.42
	2	0.430	21.42	380.59
	3	0.585	34.83
	4	0.729	45.67

Table 5. Breakthrough experiments with 200 ppm MEK as challenge contaminant

Adsorbent	Layer	Bed weight (g)	tb10% (min)	Experimental Capacity (mg/g)
ACFF 1200	1	0.180	5.33
	2	0.356	12.17	168.13
	3	0.561	19.5
	4	0.762	27.67
ACFF 1800	1	0.216	6.17
	2	0.417	12.83	165.61
	3	0.621	18.5
	4	0.769	27.83
ACFF 2000	1	0.195	6.00
	2	0.383	13.67	146.87
	3	0.652	19.83
	4	0.724	25.17

Table 6. Breakthrough experiments with 200 ppm Hexane as challenge contaminant

Adsorbent	Layer	Bed weight (g)	tb10% (min)	Experimental Capacity (mg/g)
	1	0.186	6.00
ACFF 1200	2	0.392	11.17	145.90
	3	0.540	15.83
	1	0.216	6.85
ACFF 1800	2	0.352	12.33	195.50
	3	0.681	24.17
	1	0.180	4.70
ACFF 2000	2	0.364	13.00	220.70
	3	0.515	18.67

Table 7. Maximum ACF bed depths and associated bed weights not in exceedance of 40 mm H₂0 when tested at a 10 cm/s velocity airflow. Also included are extrapolated 10% breakthrough times (T_{b 10%}) for each maximum bed weight

	Maximum Bed Depth (cm)	Maximum Bed Weight (mg)	Toluene Tb 10% (min)	MEK Tb 10% (min)	Hexane Tb 10% (min)
ACFF 1200	2.149	2.119	85.12	79.58	56.97
ACFF 1800	1.553	1.399	71.52	42.44	49.79
ACFF 2000	1.550	1.312	71.61	39.56	43.21