An Experimental Study on the Adsorption of Benzene Utilizing CuO and Alkali⁃Modified Coconut Shell Activated Carbon

doi:10.12422/j.issn.1672-6952.2025.04.004

Abstract

Abstract:

A novel adsorption material,KOH?C/CuO, was synthesized through the impregnation method using coconut shell activated carbon as support. The surface physical and chemical properties of the material were characterized by SEM,BET, FTIR,and XPS analysis. Subsequently, a benzene adsorption experiment was conducted to evaluate its performance. The influence of KOH concentration, modification time, CuO load（mass fraction), and adsorption temperature on the benzene adsorption properties was systematically investigated. Furthermore, a comprehensive evaluation of the materials' adsorption properties was carried out. The results indicated that the adsorption performance of 0.5K?C?4/CuO?3 reached its peak when the KOH concentration was 0.5 mol/L, the modification time was 4 h, the CuO load was 3%, and the temperature was maintained at 25 ℃. The adsorption capacity for benzene achieved a remarkable value of 235.3 mg/g, surpassing unmodified material by 118.88 mg/g.

Key words: CuO loading, Alkali modification, Coconut shell activated carbon, Benzene adsorption, VOCs

摘要：

采用浸渍法制备了CuO负载碱改性椰壳活性炭（KOH?C/CuO）的新型吸附材料，通过扫描电子显微镜（SEM）、比表面积测试（BET）、傅里叶红外光谱（FTIR）和X射线光电子能谱（XPS）等手段表征材料表面物理化学特性，并进行了苯吸附性能测试；考察了KOH浓度、改性时间、CuO负载量及吸附温度对材料苯吸附性能的影响，并对样品的吸附性能进行了综合评价。结果表明，在KOH浓度为0.5 mol/L，改性时间为4 h、CuO负载量（质量分数）为3%、吸附温度为25 ℃时，改性样品0.50KOH?C?4/CuO?3的吸附性能最优，其苯吸附量达235.3 mg/g，较未改性样品提升118.88 mg/g。

关键词: CuO负载, 碱改性, 椰壳活性炭, 苯吸附, VOCs

CLC Number:

O647

Tianqiang LIU, Weiwei JIAN, Qiuyan HAI, Hong ZHANG. An Experimental Study on the Adsorption of Benzene Utilizing CuO and Alkali⁃Modified Coconut Shell Activated Carbon[J]. Journal of Liaoning Petrochemical University, 2025, 45(4): 27-35.

刘天强, 建伟伟, 海秋岩, 张宏. CuO与碱改性椰壳活性炭吸附苯的实验研究[J]. 辽宁石油化工大学学报, 2025, 45(4): 27-35.

Figures/Tables 13

Fig.1 diagram of VOCs adsorption experimental setup

Fig.2 SEM images of AC, 0.50KOH?C?4, 0.50KOH?C?12, 0.50KOH?C?4/CuO amplified 10 000 times

Table 1 BET characterization results of different modified materials

吸附剂	比表面积/（m² $⋅$ g^-1）	孔径/nm	孔体积/（cm³ $⋅$ g^-1）	微孔体积/（cm³ $⋅$ g^-1）
AC	961.07	0.627	0.938	6.808
0.25KOH⁃C⁃4	982.29	0.627	0.944	6.864
0.50KOH⁃C⁃4	1 034.72	0.627	1.011	7.357
2.00KOH⁃C⁃4	830.29	0.627	0.581	5.896
0.50KOH⁃C⁃2	1 006.61	0.627	0.960	7.187
0.50KOH⁃C⁃8	969.84	0.627	0.993	6.818
0.50KOH⁃C⁃12	932.46	0.627	0.937	6.611
0.50KOH⁃C⁃4/CuO⁃3	1 069.40	0.600	1.121	7.405

Table 1 BET characterization results of different modified materials

吸附剂	比表面积/（m² $⋅$ g^-1）	孔径/nm	孔体积/（cm³ $⋅$ g^-1）	微孔体积/（cm³ $⋅$ g^-1）
AC	961.07	0.627	0.938	6.808
0.25KOH⁃C⁃4	982.29	0.627	0.944	6.864
0.50KOH⁃C⁃4	1 034.72	0.627	1.011	7.357
2.00KOH⁃C⁃4	830.29	0.627	0.581	5.896
0.50KOH⁃C⁃2	1 006.61	0.627	0.960	7.187
0.50KOH⁃C⁃8	969.84	0.627	0.993	6.818
0.50KOH⁃C⁃12	932.46	0.627	0.937	6.611
0.50KOH⁃C⁃4/CuO⁃3	1 069.40	0.600	1.121	7.405

Fig.3 XPS image of 0.50KOH?C?4/CuO?3

Fig.4 FTIR images of AC, 0.50KOH?C?4 and 0.50KOH?C?4/CuO

Table 2 Experimental conditions of benzene adsorption on modified coconut shell activated carbon

样品	KOH浓度/（mol $⋅$ L^-1）	改性时间/h	吸附温度/℃	CuO负载量/%
KOH⁃C	0.25	2~12	25	0
KOH⁃C	0.50	2~12	25	0
KOH⁃C	1.00	2~12	25	0
KOH⁃C	2.00	2~12	25	0
0.50KOH⁃C⁃4	0.50	4	25~60	0
0.50KOH⁃C⁃4/CuO	0.50	4	25	1~4
0.50KOH⁃C⁃4/CuO⁃3	0.50	4	25~60	3

Table 2 Experimental conditions of benzene adsorption on modified coconut shell activated carbon

样品	KOH浓度/（mol $⋅$ L^-1）	改性时间/h	吸附温度/℃	CuO负载量/%
KOH⁃C	0.25	2~12	25	0
KOH⁃C	0.50	2~12	25	0
KOH⁃C	1.00	2~12	25	0
KOH⁃C	2.00	2~12	25	0
0.50KOH⁃C⁃4	0.50	4	25~60	0
0.50KOH⁃C⁃4/CuO	0.50	4	25	1~4
0.50KOH⁃C⁃4/CuO⁃3	0.50	4	25~60	3

Fig.5 ffect of KOH concentration on the benzene adsorption performance of the sample

Fig.6 The benzene adsorption capacity of the sample at different KOH concentrations after 4 h modification

Fig.7 Effect of modification time with KOH on the benzene adsorption performance of the sample

Fig.8 The benzene adsorption capacity of the sample at different modification times when the KOH concentration was 0.50 mol/L

Fig.9 Effect of CuO loading amount on the benzene adsorption performance of the sample

Fig.10 The amount of benzene adsorption on the sample under different CuO loadings

Fig.11 The benzene adsorption capacity of 0.50KOH?C?4/CuO?3 and 0.50KOH?C?4 varies with temperature

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