Formation of framework supported pore for PVA/ZnO composite and Pb(Ⅱ) adsorption

doi:10.11949/j.issn.0438-1157.20181339

Abstract

Abstract:

PVA/tetra-ZnO composite was prepared by in-situ chemical crosslinking reaction which was used as the absorbent of Pb(II) in waste water. The FTIR and TGA results indicated the successful grafting of APTES on the tetra-ZnO particles surface and the tetra-ZnO particles dispersed uniformly after modification. A special “framework supported” structure was formed around the pore-channel wall of PVA/tetra-ZnO composite due to the interlocking characteristic of the tetra-ZnO particle s four whisker arms and which was beneficial for the diffusion and adsorption of heavy metal ions solution. The Pb(II) adsorption capacity reached to the maximum at 7% tetra-ZnO content, and the adsorption effect was most significant at pH 4.0. Contrary to the distribution of pore size, the absorbed Pb(II) on PVA/tetra-ZnO composite was graded distribution from the out to inside with a gradual decease trend. The Langmuir model was better fitted the Pb(II) adsorption isotherm process which revealed the homogeneous monolayer adsorption mechanism. The adsorption kinetics indicated the stepwise adsorption process due to the perfect fitting degree of pseudo-first-order model as well the pseudo-first-order model. The intraparticle diffusion kinetics model indicated that the chemical adsorption and intraparticle diffusion played the important role during the whole adsorption process. Besides, the stress stability and thermo stability of PVA/tetra-ZnO composites were improved than neat PVA.

Key words: gel, tetrapod-shaped ZnO whiskers, framework supported structure, heavy metal ions, adsorption, stability

摘要：

通过原位共交联方法制备了多孔型PVA/tetra-ZnO(聚乙烯醇/四针状氧化锌)复合材料作为废水中Pb(II)的脱除吸附剂，研究发现，由于tetra-ZnO四条晶须臂具有互锁特性使其孔壁处形成了“骨架支撑”型孔道结构，从而有利于Pb(II)的传输扩散和吸附络合。复合材料在tetra-ZnO含量为7%时具有最大Pb(II)吸附量，随pH增大，吸附量逐渐增大，复合材料的吸附效应在pH为4.0左右时最为明显。与复合材料的孔径分布相反，吸附的Pb(II)在复合材料中由外至内呈逐渐递减的梯度分布。等温吸附线表明Langmuir模型具有更好的拟合性，其吸附机理为单分子层均质吸附。动力学过程拟合表明其吸附分多步进行，化学吸附和内扩散均具有重要作用。与纯PVA相比，复合材料的应力吸附稳定性和热稳定性得到大幅提高。

关键词: 凝胶, 四针状ZnO晶须, “骨架支撑”结构, 重金属离子, 吸附, 稳定性

CLC Number:

X 131

Sheng XU, Lingli LIU, Meng CAO, Shangxi ZHANG, Xin DAI, Yang LIU, Zhenxi WANG. Formation of framework supported pore for PVA/ZnO composite and Pb(Ⅱ) adsorption[J]. CIESC Journal, 2019, 70(S1): 130-140.

徐胜, 刘玲利, 曹锰, 张尚玺, 戴欣, 柳阳, 王振希. PVA/ZnO复合材料“骨架支撑”型孔道构建及铅离子吸附[J]. 化工学报, 2019, 70(S1): 130-140.

Figures/Tables 12

Fig.1 Modification mechanism of tetra-ZnO by APTES (a), TGA curves after modification (b)

Fig.2 Macroscopic and microscopic morphology of PVA/tetra-ZnO composite

Fig.3 Mechanism of material preparation and formation of “framework supported” structure

Fig.4 Effect of tetra-ZnO content on Pb(Ⅱ) adsorption of PVA/tetra-ZnO composite

Fig.5 Adsorption isotherm behavior of PVA/tetra-ZnO composite for Pb(Ⅱ)

Table 1 Adsorption isotherm parameter of PVA/tetra-ZnO composite for Pb(II)

Adsorption isotherm model	Adsorption isotherm parameter		R ²
Langmuir	q _m	116.28 mg/g	0.9993
Langmuir	K _L	5.0 L/mg	0.9993
Freundlich	K _F	24.47 (mg/g)(mg/L) ⁿ	0.8603
Freundlich	n	2.85	0.8603
Tempkin	A _T	3.38 L/mg	0.9612
	B _T	19.35 mg/g
	b _T	128.14 (J/mol)/(mg/g)

Fig.6 Effect of pH on Pb(Ⅱ) adsorption of PVA/tetra-ZnO composite for Pb(Ⅱ)

Fig.7 Effect of contact time on Pb(Ⅱ) adsorption of PVA/tetra-ZnO composite and fitting of adsorption kinetic models

Table 2 Parameters of pseudo-first and pseudo-second order kinetic models

C ₀/(mg/L)	Pseudo-first-order			Pseudo-second-order
C ₀/(mg/L)	K _l/min^?1	q _e/(mg/g)	R ²	K ₂/(g/(mg·min))	q _e/(mg/g)	R ²
300	3.33×10^-3	93.82	0.9919	2.63×10^-5	116.28	0.9969

Fig.8 Microstructure of PVA/tetra-ZnO composite and distribution of absorbed Pb(II)

Fig.9 Microstructure and adsorption capacity of Pb(II) for neat PVA and PVA/tetra-ZnO composite under stress

Fig.10 Thermostability of PVA/tetra-ZnO composite

References 30

1	丁凡, 黄立勇, 王锐, 等 . 中国2004-2015年突发水污染事件监测数据分析[J]. 中国公共卫生, 2017, 33(1): 59-62.
	Ding F , Huang L Y , Wang R , et al . Water pollution emergencies in China, 2004—2015 :monitoring data analysis[J]. Chinese Journal of Public Health, 2017, 33(1): 59-62.
2	梁兴唐, 钟书明, 刘子杰, 等 . 甲壳素/聚乙烯亚胺复合物对水溶液中Cr(Ⅵ)的吸附[J]. 化工学报, 2018, 69(5): 2255-2262.
	Liang X T , Zhong S M , Liu Z J , et al . Chitin/polyethyleneimine composite as an adsorbent of aqueous Cr(Ⅵ)[J]. CIESC Journal, 2018, 69(5): 2255-2262.
3	Islam M S , Choi W S , Nam B , et al . Needle-like iron oxide@CaCO₃ adsorbents for ultrafast removal of anionic and cationic heavy metal ions[J]. Chemical Engineering Journal, 2017, 307: 208-219.
4	王耀强, 赵怡琳, 李玲慧, 等 . 海胆状Fe₃O₄@TiO₂磁性纳米介质对Pb²⁺的选择吸附特性[J]. 化工学报, 2018, 69(1): 446-454.
	Wang Y Q , Zhao Y L , Li L H , et al . Selective adsorption of Pb²⁺ by sea urchin magnetic nano-Fe₃O₄@TiO₂ [J]. CIESC Journal, 2018, 69(1): 446-454.
5	Ajitha P , Vijayalakshmi K , Sarany M , et al . Removal of toxic heavy metal lead (II) using chitosan oligosaccharide-graft-maleic anhydride/polyvinyl alcohol/silk fibroin composite[J]. International Journal of Biological Macromolecules, 2017, 104: 1469-1482.
6	Eligwe C A , Okolue N B , Nwambu C O , et al . Adsorption thermodynamics and kinetics of mercury (Ⅱ), cadmium (Ⅱ) and lead (Ⅱ) on lignite[J]. Chemical Engineering & Technology, 2015, 22(1): 45-49.
7	张越, 林珈羽, 刘沅, 等 . 生物炭对铅离子的吸附性能[J]. 化工环保, 2015, 35(2): 177-181.
	Zhang Y , Lin J Y , Liu Y , et al . Adsorption capability of biochar to lead ion[J]. Environmental Protection of Chemical Industry, 2015, 35(2): 177-181.
8	Yang R , Aubrecht K B , Ma H Y , et al . Thiol-modified cellulose nanofibrous composite membranes for chromium (Ⅵ) and lead (Ⅱ) adsorption[J]. Polymer, 2014, 55(5): 1167-1176.
9	Wu X , Luo L , Chen Z , et al . Syntheses, characterization and adsorption properties for Pb²⁺ of silica-gel functionalized by dendrimer-like polyamidoamine and 5-sulfosalicylic acid[J]. Applied Surface Science, 2016, 364(1): 86-95.
10	Bagher H , Afshin M , Farhood N , et al . Super high removal capacities of heavy metals (Pb²⁺ and Cu²⁺) using CNT dendrimer[J]. Journal of Hazardous Materials, 2017, 336: 146-157.
11	Reza T , Nader B , Mohammad R Z , et al . Nanospace engineering and functionalization of MCM-48 mesoporous silica with dendrimer amines based on [1,3,5]-triazines for selective and pH-independent sorption of silver ions from aqueous solution and electroplating industry wastewater[J]. Powder Technology, 2017, 321: 44-54.
12	Madadrang C J , Kim H Y , Gao G , et al . Adsorption behavior of EDTA-graphene oxide for Pb(Ⅱ) removal[J]. ACS Appl. Mater. Inter., 2012, 4(3): 1186-1193.
13	Drweesh S A , Fathy N A , Wahba M A , et al . Equilibrium, kinetic and thermodynamic studies of Pb(Ⅱ) adsorption from aqueous solutions on HCl-treated Egyptian kaolin[J]. Journal of Environmental Chemical Engineering, 2016, 4(2): 1674-1684.
14	Luo X B , Liu L L , Deng F , et al . Novel ion-imprinted polymer using crown ether as a functional monomer for selective removal of Pb(II) ions in real environmental water samples[J]. Journal of Materials Chemistry A, 2013, 1(28): 8280-8286.
15	Yang S , Hu J , Chen C , et al . Mutual effects of Pb(Ⅱ) and humic acid adsorption on multiwalled carbon nanotubes/polyacrylamide composites from aqueous solutions[J]. Environmental Science & Technology, 2011, 45(8): 3621-3627.
16	Lian Z , Ye L . Structure and properties of PVA/PEO hydrogel prepared by freezing/thawing method[J]. Journal of Applied Polymer Science, 2013, 128(5): 3325-3329.
17	Hui B , Zhang Y , Ye L . Structure of PVA/gelatin hydrogel beads and adsorption mechanism for advanced Pb(Ⅱ) removal[J]. Journal of Industrial and Engineering Chemistry, 2015, 21(1): 868-876.
18	李鲁中, 肖建霞, 王竹, 等 . 聚乙烯醇/壳聚糖/氧化石墨烯复合水凝胶的制备及对Pb(II)吸附性能研究[J]. 化工新型材料, 2016, (4): 112-115.
	Li L Z , Xiao J X , Wang Z , et al . Preparation of polyvinyl alcohol/chitosan/grapheme oxide composite hydrogel and application in removal of Pb(II) from aqueous solution[J]. New Chemical Materials, 2016, (4): 112-115.
19	Hui B , Ye L . Structure of Polyvinyl alcohol-g-acrylic acid-2-acrylamido-2-methyl-1-propanesulfonic acid hydrogel and adsorption mechanism for advanced Pb(Ⅱ) removal[J]. Journal of Industrial & Engineering Chemistry, 2016, 35: 309-317.
20	Xu S , Zhao X W , Ye L . Mechanical and crystalline properties of monomer casting nylon-6/SiO₂ composites prepared via in-situ polymerization[J]. Polymer Engineering & Science, 2013, 53(9): 1809-1822.
21	Zhang Y , Ye L . Structure and property of polyvinyl alcohol/precipitated silica composite hydrogels for microorganism immobilization[J]. Composites: Part B, 2014, 56: 749-755.
22	He J , Chen J P . Cu(Ⅱ)-imprinted poly(vinyl alcohol)/poly(acrylic acid) membrane for greater enhancement in sequestration of copper ion in the presence of competitive heavy metal ions: material development, process demonstration, and study of mechanisms[J]. Industrial & Engineering Chemistry Research, 2017, 53(52): 20223-20233.
23	王红, 夏雯, 卢平, 等 . 生物炭对土壤中重金属铅和锌的吸附特性[J]. 环境科学, 2017, 38(9): 3944-3952.
	Wang H , Xia W , Lu P , et al . Adsorption characteristics of biochar on heavy metals (Pb and Zn) in soil[J]. Environmental Science, 2017, 38(9): 3944-3952.
24	刘玲利, 徐胜, 肖慧如, 等 . 大孔型PVA/ZnO 复合凝胶制备及重金属离子选择性吸附研究[J]. 南昌工程学院学报, 2018, 37(4): 44-47.
	Liu L L , Xu S , Xiao H R , et al . Preparation of macroreticular PVA/ZnO plural gel and selective adsorption research of heavy metal ion[J]. Journal of Nanchang Institute of Technology, 2018, 37(4): 44-47.
25	Gopal R M R , Govindharajan C , Sudha P N , et al . Adsorption studies on the removal of chromium onto chitosan-g-maliec anhydride-g-ethylene dimethacrylate[J]. Journal of Chemical and Pharmaceutical Research, 2015, 7(1): 467-476.
26	王吟, 熊扬, 孙凤玲, 等 . 超声辅助高吸附型复合凝胶的制备及对水中Pb(II)的响应和去除性能[J]. 物理化学学报, 2016, 32(10): 2563-2573.
	Wang Y , Xiong Y , Sun F L , et al . Ultrasonic-assisted synthesis of a superabsorbent composite hydrogel for the responsive and removal properties of Pb(II)[J]. Acta Physico-Chimica Sinica, 2016, 32(10): 2563-2573.
27	胡秀沂 . 改性菠萝皮渣金属吸附剂及水凝胶的制备与表征[D]. 广州: 华南理工大学, 2010.
	Hu X Y . Preparation and characterization of modified pineapple peel adsorbent for metal ion and pineapple peel cellulose hydrogel[D]. Guangzhou: South China University of Technology, 2010.
28	朱倩倩, 熊春华, 厉炯慧, 等 . 吗啡啉螯合树脂对水中钨离子的吸附及解吸性能[J]. 化工学报, 2017, 68(8): 3119-3125.
	Zhu Q Q , Xiong C H , Li J H , et al . Adsorption and desorption of tungsten ions in water by morpholine chelate resin[J]. CIESC Journal, 2017, 68(8): 3119-3125.
29	Li X , Zhou H , Wu W , et al . Studies of heavy metal ion adsorption on chitosan/sulfydryl-functionalized graphene oxide composites[J]. Journal of Colloid and Interface Science, 2015, 448: 389-397.
30	Yi Z , Yao J , Chen H , et al . Equilibrium and kinetic studies on adsorption of Pb(Ⅱ) by activated palm kernel husk carbon[J]. Desalination & Water Treatment, 2016, 57(16): 7245-7253.

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