具有氧化性能混凝剂的研发及对有机物的去除效果
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摘要
通过将零价纳米铁(nZVI)与Al_(13)进行复配,研发了兼具原位氧化功能的高电荷聚合态混凝剂nZVI@Al_(13),考察了nZVI、Al_(13)不同配比和pH值等因素对有机物去除效果、分子质量分布及结构组成的影响。结果表明,混凝剂复配后,Al_(13)中高聚合态铝含量增加,提高了混凝剂的混凝效率。中性条件下,腐殖酸(HA)去除率随Al_(13)投量的增加先增大后趋于平缓,Al_(13)的最佳投量为0. 03 mmol/L,此时HA去除率约为70%;单独nZVI对HA的最大吸附去除率仅为10%; nZVI和Al_(13)复配后对HA的去除效果好于单独两种方式的加和,nZVI对Al_(13)的强化混凝起到协同作用。当pH值> 7. 0时,过多的OH~-使得Al_(13)解聚,影响混凝效果,nZVI和Al_(13)对HA的去除效果均有所下降。当pH值<7. 0时,复配混凝剂对HA的去除率均优于单独Al_(13),最大去除率达到84%。复配混凝剂对分子质量<2 000 u的有机物的去除效果较单独Al_(13)提高了约8%。
A novel coagulant (nZVI@ Al_(13)) with oxidizing ability was prepared by combining nZVI and Al_(13). The effects of dosage and p H on the organic matter (OM) removal,the molecular weight distribution and the structure composition of OM were analyzed. The results showed that the concentration of high-polymeric aluminum in Al_(13) increased after the coagulant was reconstituted, which further increased the coagulation treatment efficiency. Under neutral conditions,with the increase of Al_(13) dosage,the HA removal efficiency was firstly increased and then stabilized. The optimal Al_(13) dosage was0. 03 mmol/L,and the HA removal rate was approximately 70%. The adsorption removal rate on HA using nZVI alone was 10%. The removal efficiency of HA by nZVI @ Al_(13) was better than the total efficiency of nZVI and Al_(13) when used separately. The nZVI showed a synergistic effect on Al_(13) enhanced coagulation. At pH > 7. 0,excessive OH~- depolymerized Al_(13) and decreased the coagulation effect of the coagulant,therefore the removal efficiency of HA was reduced. At pH < 7. 0,the removal efficiency of HA by nZVI@ Al_(13) was higher than using Al_(13) separately,and the maximum removal rate reached 84%.The removal efficiency of compounded coagulants on organic matter with a molecular weight less than2 000 u was about 8% higher than that of using Al_(13) separately.
A novel coagulant (nZVI@ Al_(13)) with oxidizing ability was prepared by combining nZVI and Al_(13). The effects of dosage and p H on the organic matter (OM) removal,the molecular weight distribution and the structure composition of OM were analyzed. The results showed that the concentration of high-polymeric aluminum in Al_(13) increased after the coagulant was reconstituted, which further increased the coagulation treatment efficiency. Under neutral conditions,with the increase of Al_(13) dosage,the HA removal efficiency was firstly increased and then stabilized. The optimal Al_(13) dosage was0. 03 mmol/L,and the HA removal rate was approximately 70%. The adsorption removal rate on HA using nZVI alone was 10%. The removal efficiency of HA by nZVI @ Al_(13) was better than the total efficiency of nZVI and Al_(13) when used separately. The nZVI showed a synergistic effect on Al_(13) enhanced coagulation. At pH > 7. 0,excessive OH~- depolymerized Al_(13) and decreased the coagulation effect of the coagulant,therefore the removal efficiency of HA was reduced. At pH < 7. 0,the removal efficiency of HA by nZVI@ Al_(13) was higher than using Al_(13) separately,and the maximum removal rate reached 84%.The removal efficiency of compounded coagulants on organic matter with a molecular weight less than2 000 u was about 8% higher than that of using Al_(13) separately.
引文
[1]艾智慧,贾法龙,张礼知.常温常压纳米零价铁活化分子氧矿化三嗪类除草剂新策略[J].环境化学,2016,35(10):1977-1984.Ai Zhihui,Jia Falong,Zhang Lizhi.New strategy for mineralization of herbicides with s-triazine ring with n ZVI under room pressure and temperature[J].Environmental Chemistry,2016,35(10):1977-1984(in Chinese).
[2]程荣,王建龙,张伟贤.纳米金属铁降解有机卤化物的研究进展[J].化学进展,2006,18(1):93-99.Cheng Rong,Wang Jianlong,Zhang Weixian.The research progress on degradation of halogenated organic compounds by nano iron[J].Progress Chemistry,2006,18(1):93-99(in Chinese).
[3]罗明标,王趁义,刘淑娟,等.聚合Al13晶体的制备及表征[J].无机化学学报,2004,20(1):69-73.Luo Mingbiao,Wang Chenyi,Liu Shujuan,et al.Preparation and characterization of polynuclear Al13species[J].Chinese Journal of Inorganic Chemistry,2004,20(1):69-73(in Chinese).
[4]高宝玉,岳钦艳,王占生,等.聚硅氯化铝(PASC)的形态分布及转化规律Ⅲ.Al-Ferron逐时络合比色法与27Al-NMR法的比较[J].环境化学,2000,19(1):13-17.Gao Baoyu,Yue Qinyan,Wang Zhansheng,et al.Study on the species distribution and transformation of polyaluminum silicate chloride(PASC)Ⅲ.The comparison of species distribution in PASC and PACdetermined by Al-Ferron complexation timed spectrophotometric method with that by27Al-NMRmethod[J].Environmental Chemistry,2000,19(1):13-17(in Chinese).
[5]Agrawal A,Tratnyek P.Reduction of nitro aromatic compounds by zero-valent iron metal[J].Environ Sci Technol,1995,30:153-160.
[6]赵华章,杨宏伟,蒋展鹏,等.混凝沉淀过程中铝系混凝剂的形态转化规律[J].中国环境科学,2005,25(2):183-187.Zhao Huazhang,Yang Hongwei,Jiang Zhanpeng,et al.Transformation rule of aluminum form Al-based coagulantion and sedimentation process[J].China Environmental Science,2005,25(2):183-187(in Chinese).
[7]冯利,栾兆坤,汤鸿霄.铝的水解聚合形态分析方法研究[J].环境化学,1993,12(5):373-378.Feng Li,Luan Zhaokun,Tang Hongxiao.The study on speciation analysis methods for hydrolysis polymerization of aluminum[J].Environmental Chemistry,1993,12(5):373-378(in Chinese).
[8]Jiao R Y,Fabris R,Chow C W K,et al.Roles of coagulant species and mechanisms on floc characteristics and filterability[J].Chemosphere,2016,150:211-218.
[9]王萌萌,高宝玉,曹百川,等.无机-有机复合混凝剂处理夏季引黄水库水的对比研究[J].中国环境科学,2012,32(2):242-248.Wang Mengmeng,Gao Baoyu,Cao Baichuan,et al.Comparison of two inorganic-organic composite coagulants in treating reservoir raw water from the Yellow River[J].China Environmental Science,2012,32(2):242-248(in Chinese).
[10]Yang Z L,Gao B Y,Yue Q Y.Coagulation performance and residual aluminum specitation of Al2(SO4)3and polyaluminum chloride(PAC)in Yellow River water treatment[J].Chem Eng J,2010,165:122-132.
[11]Hu C Z,Liu H J,Qu J H,et al.Coagulation behavior of aluminum salts in eutrophic water:significance of Al13species and p H control[J].Environ Sci Technol,2006,40(1):325-331.
[12]May H M,Helmke P A,Jackson M L.Gibbsite solubility and thermodynamic properties of hydroxy-aluminum ions in aqueous solution at 25℃[J].Geochimica et Cosmochimica Acta,1979,43(6):861-868.
[13]Xu W Y,Gao B Y,Yue Q Y,et al.Effect of shear force and solution p H on flocs breakage and re-growth formed by nano-Al13polymer[J].Water Res,2010,44(6):1893-1899.
[14]曾慎亮,翁秀兰,童玉贵,等.绿色合成纳米铁同时去除水体中的Pb(Ⅱ)和Cd(Ⅱ)[J].环境科学学报,2015,35(11):3538-3544.Zeng Shenliang,Weng Xiulan,Tong Yugui,et al.Simultaneous removal of Pb(Ⅱ)and Cd(Ⅱ)from aqueous solution by green synthesized iron nanoparticle[J].Acta Scientiae Circumstantiae,2015,35(11):3538-3544(in Chinese).
[15]Jiao R Y,Chow C W,Xu H,et al.Organic removal assessment at full scale treatment facilities using advanced organic characterization tools[J].Environ Sci Process Impacts,2014,16(10):2451-2459.
[2]程荣,王建龙,张伟贤.纳米金属铁降解有机卤化物的研究进展[J].化学进展,2006,18(1):93-99.Cheng Rong,Wang Jianlong,Zhang Weixian.The research progress on degradation of halogenated organic compounds by nano iron[J].Progress Chemistry,2006,18(1):93-99(in Chinese).
[3]罗明标,王趁义,刘淑娟,等.聚合Al13晶体的制备及表征[J].无机化学学报,2004,20(1):69-73.Luo Mingbiao,Wang Chenyi,Liu Shujuan,et al.Preparation and characterization of polynuclear Al13species[J].Chinese Journal of Inorganic Chemistry,2004,20(1):69-73(in Chinese).
[4]高宝玉,岳钦艳,王占生,等.聚硅氯化铝(PASC)的形态分布及转化规律Ⅲ.Al-Ferron逐时络合比色法与27Al-NMR法的比较[J].环境化学,2000,19(1):13-17.Gao Baoyu,Yue Qinyan,Wang Zhansheng,et al.Study on the species distribution and transformation of polyaluminum silicate chloride(PASC)Ⅲ.The comparison of species distribution in PASC and PACdetermined by Al-Ferron complexation timed spectrophotometric method with that by27Al-NMRmethod[J].Environmental Chemistry,2000,19(1):13-17(in Chinese).
[5]Agrawal A,Tratnyek P.Reduction of nitro aromatic compounds by zero-valent iron metal[J].Environ Sci Technol,1995,30:153-160.
[6]赵华章,杨宏伟,蒋展鹏,等.混凝沉淀过程中铝系混凝剂的形态转化规律[J].中国环境科学,2005,25(2):183-187.Zhao Huazhang,Yang Hongwei,Jiang Zhanpeng,et al.Transformation rule of aluminum form Al-based coagulantion and sedimentation process[J].China Environmental Science,2005,25(2):183-187(in Chinese).
[7]冯利,栾兆坤,汤鸿霄.铝的水解聚合形态分析方法研究[J].环境化学,1993,12(5):373-378.Feng Li,Luan Zhaokun,Tang Hongxiao.The study on speciation analysis methods for hydrolysis polymerization of aluminum[J].Environmental Chemistry,1993,12(5):373-378(in Chinese).
[8]Jiao R Y,Fabris R,Chow C W K,et al.Roles of coagulant species and mechanisms on floc characteristics and filterability[J].Chemosphere,2016,150:211-218.
[9]王萌萌,高宝玉,曹百川,等.无机-有机复合混凝剂处理夏季引黄水库水的对比研究[J].中国环境科学,2012,32(2):242-248.Wang Mengmeng,Gao Baoyu,Cao Baichuan,et al.Comparison of two inorganic-organic composite coagulants in treating reservoir raw water from the Yellow River[J].China Environmental Science,2012,32(2):242-248(in Chinese).
[10]Yang Z L,Gao B Y,Yue Q Y.Coagulation performance and residual aluminum specitation of Al2(SO4)3and polyaluminum chloride(PAC)in Yellow River water treatment[J].Chem Eng J,2010,165:122-132.
[11]Hu C Z,Liu H J,Qu J H,et al.Coagulation behavior of aluminum salts in eutrophic water:significance of Al13species and p H control[J].Environ Sci Technol,2006,40(1):325-331.
[12]May H M,Helmke P A,Jackson M L.Gibbsite solubility and thermodynamic properties of hydroxy-aluminum ions in aqueous solution at 25℃[J].Geochimica et Cosmochimica Acta,1979,43(6):861-868.
[13]Xu W Y,Gao B Y,Yue Q Y,et al.Effect of shear force and solution p H on flocs breakage and re-growth formed by nano-Al13polymer[J].Water Res,2010,44(6):1893-1899.
[14]曾慎亮,翁秀兰,童玉贵,等.绿色合成纳米铁同时去除水体中的Pb(Ⅱ)和Cd(Ⅱ)[J].环境科学学报,2015,35(11):3538-3544.Zeng Shenliang,Weng Xiulan,Tong Yugui,et al.Simultaneous removal of Pb(Ⅱ)and Cd(Ⅱ)from aqueous solution by green synthesized iron nanoparticle[J].Acta Scientiae Circumstantiae,2015,35(11):3538-3544(in Chinese).
[15]Jiao R Y,Chow C W,Xu H,et al.Organic removal assessment at full scale treatment facilities using advanced organic characterization tools[J].Environ Sci Process Impacts,2014,16(10):2451-2459.