KOH活化法制备气化稻壳活性炭及其吸附性能

doi:10.3969/j.issn.1673-5854.2021.01.005

摘要/Abstract

摘要：

以气化稻壳炭(GRHC)为原料，KOH为活化剂制备活性炭，研究了不同活化温度和碱炭比对活性炭得率、比表面积、孔径分布以及碘值的影响。利用全自动气体吸附分析仪、X射线衍射仪、傅里叶变换红外光谱仪、扫描电镜等仪器对活性炭的理化性质进行表征，并通过吸附等温线、吸附动力学探讨其对甲基橙的吸附机制。结果表明：活化时间为1 h时，随着活化温度和碱炭比的增加，活性炭得率逐渐下降，比表面积和碘吸附值呈先增加后减少的趋势；气化稻壳炭制备活性炭的最佳工艺为碱炭比2：1、活化温度800℃、活化时间1 h，此条件下制备的活性炭得率41.73%、比表面积1 829.09 m²/g，总孔容1.007 cm³/g、碘吸附值1 984.85 mg/g、甲基橙饱和吸附量为217.87 mg/g。气化稻壳活性炭对甲基橙的吸附过程与Langmuir和Freundlich模型相关性都良好(R²>0.99)，吸附动力学更加符合准二级动力学模型。

关键词: 气化稻壳炭, 氢氧化钾法, 比表面积, 活性炭, 甲基橙, 吸附

Abstract:

Potassium hydroxide (KOH) was used as activating agent to prepare activated carbon with gasified rice husk char (GRHC) as raw material. The effects of activation temperature and mass ratio of KOH to char on the specific surface area, pore diameter distribution and iodine value of activated carbon were investigated. The physicochemical properties of activated carbon were characterized by automatic gas adsorption analyzer, X-ray diffraction, Fourier transform infrared spectrometer, and scanning electron microscope, et al. The adsorption mechanism of methyl orange was studied by adsorption isotherm and adsorption kinetics. The results showed that when the activation time was 1 h, the yield of activated carbon decreased gradually with the increase of activation temperature and alkali-carbon ratio, and the specific surface area and iodine adsorption value increased first and then decreased. The optimal conditions for preparation of activated carbon were mass ratio of KOH to char 2:1 and activation temperature of 800℃. Under these conditions, the specific surface area, total pore volume, iodine value and saturated adsorption value of methyl orange reached their maximum values of 1 829.09 m²/g, 1.007 cm³/g, 1 984.85 mg/g and 217.87 mg/g, respectively and the yield of activated carbon was 41.73%. The adsorption process of methyl orange by activated carbon was highly correlated with Langmuir and Freundlich models (R²>0.99), and the adsorption kinetics was more consistent with the pseudo-second-order kinetic model.

Key words: gasified rice husk char, KOH method, specific surface area, activated carbon, methyl orange, adsorption

中图分类号:

TQ35
TQ424

吴有龙, 徐嘉龙, 马中青, 蔡伟, 刘晓欢, 钱俊. KOH活化法制备气化稻壳活性炭及其吸附性能[J]. 生物质化学工程, 2021, 55(1): 31-38.

Youlong WU, Jialong XU, Zhongqing MA, Wei CAI, Xiaohuan LIU, Jun QIAN. Preparation of Activated Carbon from Gasified Rice Husk Char Activated by KOH and Its Adsorption Properties[J]. Biomass Chemical Engineering, 2021, 55(1): 31-38.

图/表 7

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参考文献 27

1	马中青, 张齐生, 周建斌, 等. 下吸式生物质固定床气化炉研究进展[J]. 南京林业大学学报(自然科学版), 2013, 37 (5): 139- 145.
2	马中青, 叶结旺, 赵超, 等. 基于下吸式固定床的木片气化试验[J]. 农业工程学报, 2016, 32 (增刊): 267- 274.
3	马中青, 吴有龙, 徐佳佳, 等. 两步进气法和水蒸气对竹材下吸式固定床气化性能的影响[J]. 林业工程学报, 2019, 4 (3): 93- 99.
4	蒋剑春, 孙康. 活性炭制备技术及应用研究综述[J]. 林产化学与工业, 2017, 37 (1): 1- 13. doi: 10.3969/j.issn.0253-2417.2017.01.001
5	申朋飞, 朱颖颖, 李信宝, 等. 植物基活性炭的制备及吸附应用研究进展[J]. 化工进展, 2019, 38 (8): 3763- 3773.
6	谭文英, 程晓红, 李硕, 等. KOH活化法制备棉秆基活性炭及其对含苯酚废水的吸附[J]. 生物质化学工程, 2019, 53 (2): 13- 18.
7	杨可, 李海红, 夏禹周, 等. 辣椒秸秆生物质活性炭的制备及其性能表征[J]. 材料科学与工程学报, 2019, 37 (1): 138- 143.
8	FRYDA L , VISSER R . Biochar for soil improvement:Evaluation of biochar from gasification and slow pyrolysis[J]. Agriculture, 2015, 5 (4): 1076- 1115. doi: 10.3390/agriculture5041076
9	PETERSON S C , JACKSON M A . Simplifying pyrolysis:Using gasification to produce corn stover and wheat straw biochar for sorptive and horticultural media[J]. Industrial Crops & Products, 2014, 53, 228- 235.
10	MANEERUNG T , LIEW J , DAI Y J , et al. Activated carbon derived from carbon residue from biomass gasification and its application for dye adsorption:Kinetics, isotherms and thermodynamic studies[J]. Bioresource Technology, 2015, 200, 350- 359.
11	MA Z Q , YE J W , ZHAO C , et al. Gasification of rice husk in a downdraft gasifier:The effect of equivalence ratio on the gasification performance, properties, and utilization analysis of byproducts of char and tar[J]. Bioresources, 2015, 10 (2): 2888- 2902.
12	李大伟, 马腾飞, 田原宇, 等. 碱炭比及活化温度对稻壳活性炭极微孔的影响[J]. 无机材料学报, 2015, 30 (1): 17- 22.
13	赵阳, 高建民, 郝新敏, 等. 基于KOH活化法的核桃壳基活性炭制备及其表征[J]. 安全与环境学报, 2016, 16 (2): 262- 266.
14	高磊, 董发勤, 代群威, 等. 磷酸法活化煤焦油渣制备活性炭研究[J]. 功能材料, 2012, 43 (2): 152- 155.
15	CHEN R F , LI L Q , LIU Z , et al. Preparation and characterization of activated carbons from tobacco stem by chemical activation[J]. Journal of the Air & Waste Management Association, 2017, 67 (6): 713- 724.
16	王秀芳, 田勇, 张会平. 高比表面积煤质活性炭的制备与活化机理[J]. 化工学报, 2009, 60 (3): 733- 737. doi: 10.3321/j.issn:0438-1157.2009.03.029
17	ZHANG B H , REN J W , GU X , et al. A method for the preparation of activated carbon based carbon/carbonaceous composites with controllable surface functionality[J]. Journal of Porous Materials, 2011, 18 (6): 743- 750. doi: 10.1007/s10934-010-9436-7
18	马中青, 支维剑, 叶结旺, 等. 基于TGA-FTIR和无模式函数积分法的稻壳热解机理研究[J]. 生物质化学工程, 2015, 49 (3): 27- 33.
19	刘朝霞, 牛文娟, 楚合营, 等. 秸秆热解工艺优化与生物炭理化特性分析[J]. 农业工程学报, 2018, 34 (5): 196- 203.
20	ZHANG Y M , MA Z Q , ZHANG Q S , et al. Comparison of the physicochemical characteristics of bio-char pyrolyzed from moso bamboo and rice husk with different pyrolysis temperatures[J]. BioResources, 2017, 12 (3): 4652- 4669.
21	彭何欢, 徐佳佳, 吴有龙, 等. 温度对纤维素半纤维素和木质素热解炭理化性能的影响[J]. 农业工程学报, 2018, 34 (增刊): 149- 156.
22	厉悦, 李湘洲, 刘敏. 稻壳基活性炭制备及表征[J]. 中南林业科技大学学报, 2007, 27 (6): 183- 186.
23	史月月, 单锐, 袁浩然. 改性稻壳生物炭对水溶液中甲基橙的吸附效果与机制[J]. 环境科学, 2019, 40 (6): 2783- 2792.
24	徐祺, 王三反, 孙百超. 超声改性生物炭对染料废水的吸附特性[J]. 水处理技术, 2019, 45 (3): 43- 47, 54.
25	王豆, 郭海艳, 李阳, 等. 蚓粪生物炭制备温度对甲基橙吸附性能的影响[J]. 环境工程学报, 2016, 10 (9): 5172- 5178.
26	罗平, 许杨晨, 张辉. 活性炭对印染废水的吸附性能[J]. 印染, 2016, 42 (1): 14- 20.
27	张蕊, 葛滢. 表面活性剂改性活性炭对阳离子染料的吸附[J]. 环境工程学报, 2013, 7 (6): 2233- 2238.

样品sample	工业分析proximate analysis/%			元素分析elemental analysis/%					低位热值/ (MJ·kg^-1) heat value
样品sample	灰分 ash	挥发分 volatile	固定碳 fixed carbon	C	H	O	N	S	低位热值/ (MJ·kg^-1) heat value
稻壳rice husk	31.87	60.03	8.10	37.41	5.73	55.72	0.95	0.19	10.87
气化稻壳炭GRHC	54.38	11.78	33.84	35.46	1.53	62.83	0.01	0.17	12.88

制备条件 preparation condition		得率/% yield	比表面积/ (m²·g^-1) specificsurfa cearea	总孔容积/ (cm³·g^-1) total pore volume	微孔容积/ (cm³·g^-1) micropore volume	中孔容积/ (cm³·g^-1) mesopore volume	微孔率/% micropore ratio	中孔率/% mesopore ratio	碘吸附值/ (mg·g^-1) iodine value
气化稻壳炭GRHC			154.07	0.155	0.013	0.068	8.40	43.96	96.37
碱炭比 mass ratio of KOH/char	1:1	45.16	1166.45	0.590	0.409	0.059	69.28	9.99	1277.05
	2:1	41.73	1829.09	1.007	0.574	0.228	57.00	22.64	1984.85
	3:1	38.64	1380.44	0.762	0.461	0.113	60.54	14.84	1504.85
活化温度 activation temperature	600 ℃	53.21	1058.88	0.479	0.243	0.126	50.73	26.30	923.50
	700 ℃	47.36	1365.75	0.650	0.357	0.153	54.92	23.54	1187.58
	800 ℃	41.73	1829.09	1.007	0.574	0.228	57.00	22.64	1984.85
	900 ℃	33.51	1528.90	0.810	0.434	0.160	53.59	19.76	1449.50

[1]	孙昊, 孙云娟, 缪存标, 孙康, 蒋剑春. 我国活性炭产业发展典型案例分析——以福建元力活性炭股份有限公司为例[J]. 生物质化学工程, 2021, 55(1): 1-9.
[2]	邱子言, 王怀, 罗诗兰, 胡飞龙, 黄钦, 宋湛谦. 松香基表面活性剂调控制备NiO纳米微球及其吸附刚果红[J]. 生物质化学工程, 2021, 55(1): 39-48.
[3]	靳珂, 陆倩, 马来九, 李惠娟, 史正军. 核桃壳炭的制备及其对氨氮废水的吸附性能研究[J]. 生物质化学工程, 2021, 55(1): 63-69.
[4]	王丽娜, 马晓军. 植物纤维素基碳气凝胶的制备及应用研究进展[J]. 生物质化学工程, 2021, 55(1): 83-90.
[5]	江山竹, 王夺, 尹俊钧, 刘运权, 李水荣, 叶跃元. 银基活性炭对废轮胎热解油的吸附脱硫机理研究[J]. 生物质化学工程, 2020, 54(6): 33-38.
[6]	吕鹏,王光辉,王冰,胡德玉. 热解温度和生物质类型对生物炭吸附U(Ⅵ)性能的影响[J]. 生物质化学工程, 2020, 54(5): 15-24.
[7]	建晓朋,许伟,侯兴隆,刘石彩. 活性炭改性技术研究进展[J]. 生物质化学工程, 2020, 54(5): 66-72.
[8]	任杰,万力,陈楠纬,杨帆,孙水裕,任随周. 咖啡渣活性炭的制备、表征及其对Cr(Ⅵ)的吸附机制研究[J]. 生物质化学工程, 2020, 54(4): 1-8.
[9]	徐茹婷,许伟,卢辛成,孙康. 磷酸法木质活性炭除灰新工艺研究[J]. 生物质化学工程, 2020, 54(4): 37-41.
[10]	李瑶,于淼,吕冬,王立娟. 蒲草叶基活性炭的制备及性能研究[J]. 生物质化学工程, 2020, 54(3): 9-17.
[11]	费海燕,田亚萍,李晗,范方宇,王昌命,郑志锋. 油茶壳微孔活性炭的制备及表征[J]. 生物质化学工程, 2020, 54(3): 25-30.
[12]	常帅帅,张学杨,王洪波,李梅,谭珍珍. 木屑生物炭的制备及其对Pb²⁺的吸附特性研究[J]. 生物质化学工程, 2020, 54(3): 37-44.
[13]	王佳楠,羿颖,边勇军,马媛媛,刘志明. 羟甲基化木质素/纤维素气凝胶粒子的制备、表征及吸附性能[J]. 生物质化学工程, 2020, 54(1): 16-22.
[14]	孙万里. 茶皂素提取条件的优化及纯化研究[J]. 生物质化学工程, 2019, 53(6): 39-44.
[15]	邓丛静,马欢欢,周建斌. 改性杏壳活性炭的制备、表征及其吸附乙烯性能[J]. 生物质化学工程, 2019, 53(5): 1-8.