Study on adsorption capacity of VOCs on activated carbon at medium-high temperature

doi:10.11949/0438-1157.20190669

Abstract

Abstract:

A total of 5 kinds of activated carbons were selected, including 3 kinds of commercial activated carbons, one of which was impregnated with HCl solution and KOH solution, to study the influence of space velocity and adsorption temperature on the adsorption of volatile organic compounds (VOCs), and the influence of types of VOCs and characteristics of adsorbents on the adsorption and desorption of VOCs at high temperature and low concentration. It was found that the space velocity had a great effect on the adsorption penetration time, but did not affect the adsorption capacity. Adsorption temperature and the concentration of VOCs was found to have a great influence on the adsorption capacity, and when the adsorption temperature was 150℃, adsorption capacity of adsorbent to toluene can only reach 40% of that at 90℃. High-boiling adsorbates are more easily adsorbed and more difficult to desorb.

Key words: VOCs, activated carbon, adsorption, boiling point, desorption

摘要：

选用3种商用活性炭及其分别经HCl溶液和KOH溶液浸渍改性的商用活性炭，研究中高温烟气环境下，反应空速、吸附温度对挥发性有机物（VOCs）吸附性能的影响，以及VOCs种类、吸附剂特性等与VOCs吸脱附效果的关系。研究发现：空速对吸附穿透时间影响较大，但对饱和吸附量影响不显著。吸附温度与VOCs浓度对饱和吸附量存在较大影响，150℃时甲苯的饱和吸附量仅能达到90℃时的40％。高沸点吸附质更易被吸附，更难被脱附。

关键词: VOCs, 活性炭, 吸附, 沸点, 脱附

CLC Number:

X 51

Zhi ZHANG, Xiuwei MA, Jinjin LI, Linjun YANG. Study on adsorption capacity of VOCs on activated carbon at medium-high temperature[J]. CIESC Journal, 2019, 70(12): 4811-4820.

张智, 马修卫, 李津津, 杨林军. 中高温环境下VOCs在活性炭上的吸附性能研究[J]. 化工学报, 2019, 70(12): 4811-4820.

Figures/Tables 10

References 30

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吸附质	分子量	沸点/℃	偶极矩/D^①	相对介电常数	分子最大横截面积/nm²
苯	78.11	80.1	0	2.274~2.292	0.4946
甲苯	92.14	110.6	0.375	2.364~2.385	0.5189
对二甲苯	106.167	138.5	0	2.22~2.273	0.5681
对二氯苯	147	174	0	2.394	0.6354
苯酚	94.11	181.9	1.224	9.78~12.40	0.5053

吸附质	分子量	沸点/℃	偶极矩/D^①	相对介电常数	分子最大横截面积/nm²
苯	78.11	80.1	0	2.274~2.292	0.4946
甲苯	92.14	110.6	0.375	2.364~2.385	0.5189
对二甲苯	106.167	138.5	0	2.22~2.273	0.5681
对二氯苯	147	174	0	2.394	0.6354
苯酚	94.11	181.9	1.224	9.78~12.40	0.5053

吸附剂	比表面积/(m²/g)		孔容/(cm³/g)		平均孔径/nm
吸附剂	总比表面积	微孔	总孔容	微孔	平均孔径/nm
HYK	931.09	911.56	0.44	0.38	1.90
KYK	932.60	917.12	0.42	0.38	1.93
YK	937.59	928.81	0.45	0.39	1.91
MU	148.14	140.73	0.09	0.06	2.41
MEI	803.1	749.51	0.47	0.33	2.33

吸附剂	比表面积/(m²/g)		孔容/(cm³/g)		平均孔径/nm
吸附剂	总比表面积	微孔	总孔容	微孔	平均孔径/nm
HYK	931.09	911.56	0.44	0.38	1.90
KYK	932.60	917.12	0.42	0.38	1.93
YK	937.59	928.81	0.45	0.39	1.91
MU	148.14	140.73	0.09	0.06	2.41
MEI	803.1	749.51	0.47	0.33	2.33

吸附剂	元素含量/%			官能团含量/%
吸附剂	C	O	N	石墨碳	C—O	CO	COOH
HYK	90.46	8.26	1.28	60.98	11.59	10.98	7.93
KYK	91.36	7.15	1.49	63.29	12.03	9.50	7.59
YK	91.12	7.74	1.14	64.52	10.32	6.45	8.39
MU	85.52	13.32	1.16	59.17	15.98	7.69	8.88
MEI	87.12	10.77	2.11	60.98	12.80	6.71	9.15