改性加拿大一枝黄花去除水中Cr(Ⅵ)的特性分析
Adsorption of Cr(Ⅵ) from aqueous solution by modified Solidago canadensis
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摘要: 以生物入侵植物加拿大一枝黄花为原料,利用环氧氯丙烷、氢氧化钠和三乙胺对其进行化学改性,制备出含季铵基的吸附剂.采用元素分析、扫描电镜、X射线衍射、红外光谱、氮气吸附和X射线光电子能谱等手段对改性前后加拿大一枝黄花物理化学性质进行表征,并通过批实验的方法探讨了改性前后加拿大一枝黄花对Cr(Ⅵ)的吸附行为及热力学性质.结果表明,加拿大一枝黄花改性后纤维素内部产生了爆裂式膨胀,含氮量增加,引入了季铵基,吸附Cr(Ⅵ)离子能力显著提高.吸附实验结果表明,改性加拿大一枝黄花吸附去除Cr(Ⅵ)的平衡时间约为3 h,pH值为1—7范围内吸附效果较好.吸附过程符合准二级动力学模型,并均能较好地符合Langmuir和Freundlich等温吸附模型(R2> 0.95),298 K时最大吸附量为29.62 mg·g-1.应用van't Hoff 方程对吸附热力学参数进行了计算,结果表明Cr(Ⅵ)在改性加拿大一枝黄花上的吸附为熵加的自发物理吸热过程.Abstract: Solidago canadensis was modified with epichlorohydrin, sodium hydroxide and triethylamine for the removal of hexavalent chromium from aqueous solution. The modified Solidago Canadensis (MSC) was characterized by element analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD), infrared spectroscopy (FTIR), nitrogen adsorption and X-ray photoelectron spectroscopy (XPS). The adsorption of hexavalent chromium from aqueous solutions with MSC which contained amine groups was investigated under several conditions in batch methods. The results showed that the hollow shape was formed along the longitudinal cellulose strongly, and nitrogen content in MSC was increased. Batch adsorption experimental results indicated that adsorption behavior of MSC was significantly depending on pH, contact time, and initial concentration of Cr(Ⅵ). The adsorption equilibrium time was about 3 hours, and the proper pH range was 1—7. Kinetic data were best fitted with the pseudo-second-order kinetic model. The batch equilibrium data was fitted well to both Langmuir and Freundlich adsorption model (R2> 0.95). Maximum adsorption capacity of MSC for Cr(Ⅵ) was 29.62 mg·g-1 at 298 K. Thermodynamic parameters such as standard Gibbs free energy (ΔG0), standard enthalpy (ΔH0), and standard entropy (ΔS0) were evaluated by applying the van't Hoff equation. The obtained thermodynamic parameters showed that the adsorption of Cr(Ⅵ) onto MSC was a spontaneous and endothermic process.
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Key words:
- modified Solidago Canadensis /
- Cr(Ⅵ) /
- adsorption /
- isotherms /
- kinetics /
- thermodynamics.
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[1] [2] WANG J H, ZHANG X, ZHANG B, et al. Rapid adsorption of Cr(Ⅵ) on modified halloysite nanotubes [J]. Desalination, 2010, 259(1-3): 22-28. [3] CHEN S H, YUE Q Y, GAO B Y, et al. Removal of Cr(Ⅵ) from aqueous solution using modified corn stalks: Characteristic, equilibrium, kinetic and thermodynamic study [J]. Chemical Engineering Journal, 2011, 168(2): 909-917. [4] 李荣华,张增强,孟昭捐,等.玉米秸秆对Cr(Ⅵ)的生物吸附及热力学特征研究[J].环境科学学报,2009, 29(7): 1434-1441. LI R H, ZHANG Z Q, MENG Z J, et al. Biosorption of Cr(Ⅵ) by corn stalk biomass: thermodynamics and mechanism [J]. Acta Scientiae Circumstantiae, 2009, 29(7): 1434-1441 (in Chinese).
[5] 曹威.改性稻草去除水中SO42-和Cr(Ⅵ)的特性和机理研究[D]. 广州:华南理工大学博士学位论文, 2012. CAO W. Study on the removal of sulphate and Cr(Ⅵ) from water by modified rice straw: Characteristics and mechanism [D]. Guangzhou: Dissertation for Doctoral Degree, South China University of Technology, 2012 (in Chinese). [6] 高悦,许醒,高宝玉,等. 生物质阴离子树脂的合成、表征及吸附性能[J]. 化工学报, 2012, 63(1): 301-306. GAO Y, XU X, GAO B Y, et al. Preparation, characteristics and adsorption properties of anion resin prepared from biomass [J]. CIESC Journal, 2012, 63(1): 301-306 (in Chinese).
[7] 杨如意,昝树婷,唐建军,等. 加拿大一枝黄花的入侵机理研究进展[J]. 生态学报, 2011, 31(4): 1185-1194. YANG R Y, ZAN S T, TANG J J, et al. Invasion mechanisms of Solidago canadensis L.: A review [J]. Acta Ecologica Sinica, 2011, 31(4): 1185-1194 (in Chinese).
[8] SUN B Y, TAN J Z, WAN Z G, et al. Allelopathic effect of ectracts from Solidago canadensis against seed germination and seeding growth of some plants [J].Journal of Environmental Science, 2006, 18(2): 304-309. [9] ZHANG S S, JIN Y L, TANG J J. The invasive plant Solidago canadensis suppresses local soil pathogens through allelopathy [J]. Applied Soil Ecology, 2009, 41(2): 215-222. [10] ŠUTOVSKÁ M, CAPEK P, KOCMÁLOVÁ M, et al. Characterization and biological activity of Solidago canadensis complex[J]. International Journal of Biological Macromolecules, 2013, 52:192-197. [11] 罗来盛. KOH活化制备加拿大一枝黄花微孔活性炭及表征[J].上海环境科学, 2013, 32(3):120-124. LUO L S. Preparation and characterisation of microporous activated carbon from Solidago canadensis by potassium hydroxide activation [J]. Shanghai Environmental Sciences, 2013, 32(3):120-124 (in Chinese).
[12] 罗来盛,孙利红,余阳,等. 微波活化法制备加拿大一枝黄花活性炭及其性能表征[J].环境工程学报, 2011, 5(5):1161-1165. LUO L S, SUN L H, YU Y, et al. Preparation and characterization of activated carbon from Solidago canadensis by means of microwave irradiation activation [J]. Chinese Journal of Environmental Engineering, 2011, 5(5):1161-1165 (in Chinese).
[13] 杨再福,曾钰.加拿大一枝黄花纤维素合成吸油材料的工艺条件与吸附性能[J]. 化学反应工程与工艺, 2012, 28(2):138-142. YANG Z F, ZENG Y. Synthesis conditions and oil adsorption of oil sorbents synthesized from cellulose of Solidago canadensis L [J]. Chemical Reaction Engineering and Technology, 2012, 28(2):138-142 (in Chinese).
[14] 黄色燕,刘云凤,曹威,等.改性稻草对Cr(Ⅵ)的吸附动力学[J].环境化学, 2013, 32(2):240-248. HUANG S Y, LIU Y F, CAO W, et al. Adsorption kinetics of Cr(Ⅵ) onto modified rice straw [J]. Environmental Chemistry, 2013, 32(2):240-248 (in Chinese).
[15] CHEN S H, YUE Q Y, GAO B Y, et al. Preparation and characteristics of anion exchanger from corn stalks[J].Desalination, 2011,274(1-3): 113-119. [16] ANIRUDHAN T S, JALAJAMONY S, SUCHITHRA P S. Improved performance of cellulose based anion exchange with tertiary amine functionality for the adsorption of Cr(Ⅵ) from aqueous solution [J].Colloids and surfaces A: Physicochemical and Engineering Aspects, 2009, 335(1-3): 107-113. [17] XU X, GAO B Y, TANG X, et al. Characteristics of cellulosic amine-crosslinked copolymer and its sorption properties for Cr(Ⅵ) from aqueous solutions [J]. Journal of Hazardous Materials, 2011,189 (1-2): 420-426. [18] 曹威,党志. 季铵化改性稻草吸附去除水中 SO42-的特性研究[J].环境科学学报, 2013, 33(9):2466-2472. CAO W, DANG Z. Adsorption of sulphate from aqueous solution by quaternary amine-modified rice straw [J]. Acta Scientiae Circumstantiae, 2013, 33(9):2466-2472 (in Chinese).
[19] CHEN S H, YUE Q Y, GAO B Y, et al. Equilibrium and kinetic adsorption study of the adsorptive removal of Cr(Ⅵ) using modified wheat residue [J]. Journal of Colloid and Interface Science, 2010, 349:256-264. [20] BARAL S S, DAS S N, CHAUDHUIY G R, et al. Adsorption of Cr(Ⅵ) using thermally activated weed Salvinia cucullata [J]. Chemical Engineering Journal, 2008, 139(2):245-255. [21] 曹玉娟,张扬,夏军,等. ε-聚赖氨酸生产废菌体对六价铬吸附影响的研究[J].环境科学, 2012, 33(2): 499-504. CAO Y J, ZHANG Y, XIA J, et al. Biosorption of chromium (Ⅵ) by waste biomass of ε-poly-L-lysine fermentation [J]. Environmental Science, 2012, 33(2): 499-504 (in Chinese).
[22] 陈云,于永鲜,张金利,等.铁氧化物改性黏土对Cr(Ⅵ)的吸附性能研究[J].环境科学学报, 2011, 31(5): 905-911. CHEN Y, YU Y X, ZHANG J L, et al. Adsorption of Cr(Ⅵ) by iron oxide-modified clay [J]. Acta Scientiae Circumstantiae, 2011, 31(5): 905-911 (in Chinese).
[23] 唐文清,冯泳兰,李小明.掺硅碳羟基磷灰石的制备及其对Pb2+的吸附性能[J].中国环境科学, 2013, 33(6): 1017-1024. TANG W Q, FENG Y L, LI X M. Adsorption characteristics of Pb2+ from aqueous solution and synthetic silicon-substituted carbonate hydroxyapatite particles [J]. China Environmental Science, 2013, 33(6): 1017-1024 (in Chinese).
[24] 李爱民,张全兴,刘富强,等.一种亲水的酚羟基修饰聚苯乙烯树脂对酚类化合物的吸附热力学[J].离子交换与吸附, 2001, 17(6): 515-525. LI A M, ZHANG Q X, LIU F Q, et al. Thermodynamic study of adsorption of phenolic compounds on a phenol hydroxyl modified polystyrene [J]. Ion Exchange and Adsorption, 2001, 17(6): 515-525 (in Chinese).
[25] 舒月红,贾晓珊. CTMAB-膨润土从水中吸附氯苯类化合物的机理——吸附动力学与热力学[J].环境科学学报, 2005, 25(11): 1530-1536. SHU Y H, JIA X S. The mechanisms for CTMAB-bentonites to adsorb CBs from water in the adsorption kinetics and thermodynamics view [J]. Acta Scientiae Circumstantiae, 2005, 25(11): 1530-1536 (in Chinese).
[26] 程华丽,李瑾,王涵,等. 壳聚糖/蒙脱土插层复合物对活性红染料的吸附动力学及解吸性能[J].环境化学, 2014, 33(1): 115-122. CHENG H L, LI J, WANG H, et al. Adsorption kinetics of chitosan/montmorillonite intercalation composites for Reactive Red dye and desorption properties [J]. Environmental Chemistry, 2014, 33(1): 115-122 (in Chinese).
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