以丙烯酸(AA)为单体,腐植酸钾(KHA)和壳聚糖(CTS)为原料,过硫酸钾(KPS)为引发剂,N,N-亚甲基丙烯酰胺(MBA)为交联剂,采用水溶液聚合法制备出KHA/CTS/AA水凝胶型吸附剂。采用扫描电子显微镜、傅里叶变换红外光谱仪、X射线衍射仪和物理吸附仪等对吸附剂的形貌、结构进行表征,通过吸附热力学和动力学对吸附阳离子染料亚甲基蓝(MB)的过程进行了研究。结果表明:KHA/CTS/AA对MB的吸附量随着初始质量浓度增大而提高,随着pH的升高先增加后逐渐减小,吸附量随着温度的升高而增加。KHA/CTS/AA用量为50mg,MB溶液为100mL,MB初始质量浓度为1050mg/L,pH=5,温度为318K时,吸附量达到最大值880.246mg/g。KHA/CTS/AA对MB的吸附符合Lagergren准二级动力学方程和Freundlich吸附等温模型。热力学分析结果表明,KHA/CTS/AA对MB的吸附机理主要包括静电引力、氢键、范德华力、离子交换等方式。
Acrylic acid (AA) used as monomer,potassium humate (KHA) and chitosan (CTS) as raw materials,potassium persulfate (KPS) as initiator,and N,N-bis methacrylamide (MBA) as crosslinking agent,KHA/CTS/AA hydrogel type adsorbent was prepared by aqueous solution polymerization.The morphology and structure of the composites were characterized by SEM,FT-IR,XRD and physical adsorber.The adsorption of cationic dye methylene blue (MB) by the composites was researched by adsorption thermodynamics and kinetics.The results shown that the adsorption amount for MB increased with the increase of the initial concentration,increased first and then decreased with the increase of pH value,and increased with the increase of temperature.When the composites was 50mg,the MB dye solution was 100mL,C0=1050mg/L,pH=5 and T=318K,the adsorption amount reached a maximum value of 880.246mg/g.The adsorption for MB conformed to Lagergren quasi-second-order kinetic equation and Freundlich-type adsorption isotherm model.The kinetic results indicated that the main control step for the MB adsorption rate of the composites was intraparticle diffusion.Thermodynamic results shown that the adsorption mechanism of the composites on MB dyes mainly included electrostatic attraction,hydrogen bonding,Van der Waals force and ion exchange.
[1] 刘志雄, 孙琳, 胡洁, 等.CuFeO2的制备、表征及对亚甲基蓝的吸附性能[J].精细化工, 2017, 34(4):444-450.
[2] 成绍鑫, 孙淑和, 李善祥, 等.腐植酸和硝基腐植酸的结构研究[J].燃料化学学报, 1983, 11(2):26-39.
[3] 李威, 邹立壮, 朱全书, 等.近十年腐植酸应用研究综述[J].腐植酸, 2006, 30(3):3-8.
[4] Arroyave J M, Waiman C C, Zanini G P, et al.Effect of humic acid on the adsorption/desorption behavior of glyphosate on goethite.Isotherms and kinetics[J].Chemosphere, 2016, 14(5):34-41.
[5] Giasuddin A B, Kanel S R, Choi H.Adsorption of humic acid onto nanoscale zerovalent iron and its effect on arsenic removal[J].Environmental Science & Technology, 2007, 41(6):2022-2027.
[6] Khansaa Al-Essa, Fawwaz Khalili.Adsorption of humic acid onto jordanian kaolinite clay:effects of humic acid concentration, pH, and temperature[J].Science Journal of Chemistry, 2018, 6(1):1-10.
[7] 靳廷甲, 章祥林, 徐建, 等.铁酸锰/腐植酸复合材料制备及其对亚甲基蓝吸附性能[J].应用化学, 2016, 33(3):336-342.
[8] Islam S, Bhuiyan M A R, Islam M N.Chitin and chitosan:structure, properties and applications in biomedical engineering[J].Journal of Polymers & the Environment, 2016, 20:1-13.
[9] Kumar A S K, Jiang S J.Chitosan-function-alized graphene oxide:a novel adsorbent an efficient adsorption of arsenic from aqueous solution[J].Journal of Environmental Chemical Engineering, 2016, 4(2):1698-1713.
[10] Khan S A, Khan S B, Kamal T, et al.Antibacterial nanocomposites based on chitosan/Co-MCM as a selective and efficient adsorbent for organic dyes[J].International Journal of Biological Macromolecules, 2016, 91:744-751.
[11] 范红伟, 周丽梅, 蒋晓慧, 等.不同微环境有机蒙脱土的制备及吸附亚甲基蓝的研究[J].西华师范大学学报:自然科学版, 2014, 35(1):21-27.
[12] 席永慧, 赵红.粉煤灰及膨润土对Ni2+, Zn2+, Cd2+, Pb2+的吸附研究[J].粉煤灰综合利用, 2004(3):3-7.
[13] 辛琳琳, 王锦, 景传勇, 等.复合吸附材料TLA的制备及其砷氟共除性能的研究[J].环境科学学报, 2010, 30(2):375-382.
[14] Kumar P, Prasad B, Mishra I M, et al.Decolorization and COD reduction of dyeing wastewater from a cotton textile mill using thermolysis and coagulation[J].Journal of Hazardous Materials, 2008, 153(1):635-645.
[15] 吴焕领, 魏赛男, 崔淑玲, 等.吸附等温线的介绍及应用[J].染整技术, 2006, 28(10):12-14.
[16] Garcia-Delgado R A, Cotouelo-Minguez L M, Rodriguez J J, et al.Equilibriumstudy of single soluteadsorption of anionic surfactants with polymeric XAD resins[J].Sep Sci Technol, 1992, 27(7):975-978.
[17] Sableviciene D, Klimaviciute R, Bendoraitiene J, et al.Flocculation properties of high-substituted cationic starches[J].Colloids and Surfaces A:Physicochemical and Engineering Aspects, 2005, 259(1/2/3):23-30.
[18] Yang W C, Liu W P, Liu H J, et al.Adsorption and correlation with their thermo dynamic properties of triazine herbicides on soils[J].Journal of Environmental Sciences, 2003, 15(4):443-448.
[19] Hou W J, Jian Y U.Development of printing and dyeing wastewater treatment processes[J].Industrial Water & Wastewater, 2004, 51(9):925-933.
[20] Georgiou D, Melidis P, Aivasidis A, et al.Degradation of azo-reactive dyes by ultraviolet radiation in the presence of hydrogen peroxide[J].Dyes & Pigments, 2002, 52(2):69-78.
[21] Lim C L, Morad N, Teng T T, et al.Treatment of terasil red R dye wastewater using H2O2/pyridine/Cu(Ⅱ) system[J].Journal of Hazardous Materials, 2009, 168(1):383-389.