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聚硅氯化铝(PASC)的形态分布及转化规律——Ⅱ.27Al-NMR法研究PASC溶液中铝的形态分布  [PDF]
高宝玉,岳钦艳,王占生,汤鸿霄
环境化学 , 2015,
Abstract: 采用27Al-NMR法比较研究了PASC与PAC中铝的形态分布.实验结果表明,在PASC中,由于聚硅酸与铝水解聚合产物间的相互作用,使得铝的水解聚合形态分布及转化情况发生了变化.在相同B值条件下,PASC中Al单和Al13的含量低于PAC中相应Al单和Al13的含量,而PASC中Al其它的含量却大于PAC中Al其它的含量,其差值随着碱化度(B)和Al/Si摩尔比的减小而增大.共聚法制备的PASC(共)与复合法制备的PASC(复)相比较,PASC(复)具有较高的Al单和Al13含量,较低的Al其它.含量、这说明制备工艺对PASC中铝的形态分布具有一定的影响.
聚硅氯化铝(PASC)的形态分布及转化规律——Ⅰ.Al-Ferron逐时络合比色法研究PASC溶液中铝的形态分布及转化规律  [PDF]
高宝玉,岳钦艳,王占生,汤鸿霄
环境化学 , 2015,
Abstract: 采用Al-Ferron逐时络合比色法比较研究了PASC与PAC中铝的形态分布及转化规律.实际结果表明,在PASC中,由于聚硅酸与铝水解聚合产物间的相互作用,使得铝的水解聚合形态分布及转化情况发生了变化.在相同B值条件下,PASC中Ala和Alb的含量低于PAC中相应Alc和Alb的含量,而PASC中Alc的含量却大于PAC中Alc的含量.共聚法制备的PASC(共)与复合法制备的PASC(复)相比较,PASC(复)具有较高的Ala和Alb含量,较低的Alc含量.这说明制备工艺对PASC中铝的形态分布具有一定的影响.
高浓度聚硅氯化铝(PASC)中铝的水解-聚合特性研究  [PDF]
高宝玉,刘莉莉,周维芝,岳钦艳,李倩
环境科学学报 , 2005,
Abstract: 以铝酸钠为碱化剂,采用缓慢滴碱法合成了高浓度(2.0mol.L-1左右)具有不同Si/Al摩尔比的聚硅氯化铝复合混凝剂(PASC).采用Al-Ferron逐时络合比色法、碱式滴定法和红外光谱分析,研究了铝的形态分布、水解-聚合历程及铝硅间的相互作用.实验结果表明,Al-Ferron络合动力学符合At=A0+A11-exp(-kb1t+A2-exp(-kb2t);在PASC中,硅酸钠和铝的水解产物间存在着相互作用,这种作用对铝的水解-聚合历程和形态分布有不同程度的影响.用铝酸钠制备PASC时有利于Al的形态由低聚物向中、高聚物转化,且随着PASC中Si/Al比的增加生成多核羟铝配合物的能力逐渐增强.
Speciation of the reactive hydroxyl-Al polymers with Al-Ferron reaction kinetics and 27Al NMR spectroscopy
活性羟基铝聚合体形态的AlFerron反应动力学与核磁共振光谱分析

FENG Chenghong,TANG Hongxiao,
冯成洪
,汤鸿霄

环境科学学报 , 2007,
Abstract: 依据不同形态结构铝与Ferron络合反应动力学差异,采用A1-Ferron络合反应动力学曲线拟和计算模式将不同温度下(25℃和80℃)制备的不同碱化度(B=0.5~2.5)的羟基聚合铝溶液中羟基铝分成单体铝(A1a)、活性羟基聚合铝(A1b)和惰性凝胶高聚体铝(A1c)3种形态.此外,结合NMR光谱,Alb进一步分成六圆环结构的快速反应聚合铝(Alb1)和以Al13为主体的慢速反应聚合铝(Alb2).A1bl和Alh2与Ferron络合反应动力学差异明显,动力学常数分别为(1-3)×10-2和(0.6~3)×10-3.Al-Ferron络合反应动力学拟和计算模式可替代核磁共振光谱对溶液中的Al13含量进行测定分析.
Preparation of Polyaluminum Silicate Chloride (PASC) from Tetraethylorthosilicate (TEOS) and Its Physicochemical Characteristics
以TEOS为硅源的聚硅氯化铝絮凝剂的制备及其物化特征

ZHAO Hua zhang,WANG Hong yu,ZUO Hu,LUAN Zhao kun,PEI Yuan sheng,
赵华章
,王红宇,左华,栾兆坤,裴元生

环境科学 , 2004,
Abstract: A new type of polyaluminum silicate chloride PASC(A)] was prepared by employing tetraethylorthosilicate (TEOS) as silicon source. By comparing PASC(A) with the conventional product PASC(B)], the effects of B value and Si/Al molar ratio on the pH value and the Zeta potential of PASC(A) were investigated. The influence of the incorporation of silicon into PASC on the molecular structure and aluminium species was also studied by acidification method and 27Al NMR spectroscopy. The results show that the PASC(A) has higher polymerization degree, narrow distribution of molecular weight and symmetrical distribution of aluminium and silicon in PASC molecule. It is more difficult to be acidified, and moreover, it can reduce the loss of Al13 species. All the above advantages of PASC(A) are due to its special synthesis method.
Study on the hydrolysis-polymerization process of aluminum in polyaluminum silicate chloride(PASC) flocculant
高浓度聚硅氯化铝(PASC)中铝的水解-聚合特性研究

GAO Baoyu,LIU Lili,ZHOU Weizhi,YUE Qinyan,LI Qian,
高宝玉
,刘莉莉,周维芝,岳钦艳,李倩

环境科学学报 , 2005,
Abstract: Using NaAlO2 as basification agent, the high-concentration (about 2.0 (mol·L-1)) flocculants polyaluminum silicate chloride (PASC) with different Si/Al molar ratio were prepared by feeding the alkali slowly. The species distribution and transformation were detected by Ferron timed complexation spectrophotometry. And the hydrolysis-polymerization process of aluminum in PASCsolution was investigated by NaOHtitration method. And the interaction between hydrolyzed aluminum species and polysilicic acid in PASCwere studied by IRmeasurements. It was found that the kinetics curve of Al-Ferron timed complexation accorded with At=A0+A11-exp(-k-b1t]+A2-exp(-kb2t)] equation. It was also found that there were interactions between polysilicic aid and hydrolyzed aluminum species in PASC, and these interactions could partially affect the hydrolysis-polymerization processes and the aluminum species distribution. The aluminum species could change from low polymer into high polymers easily when NaAlO2 was used as basification agent. The higher the Si/Al ratio was, the more the polymerize aluminum species were.
新型复合无机高分子混凝剂——聚硅氯化铝(PASC)的净水效果研究  [PDF]
高宝玉,岳钦艳,张玲,王媛
环境科学学报 , 2002,
Abstract: 采用共聚方法制备了系列具有不同碱化度(B)和Al/Si摩尔比的聚硅氯化铝(PASC),比较了它们与聚合氯化铝(PAC)的混凝效果及在处理后水中的残留铝含量,研究了B值和pH值对其残留铝含量的影响情况.探讨了PASC的混凝效果和残留铝含量与Al/Si摩尔比之间的关系.结果表明,PASC较PAC具有更好的混凝效果和较低的残留铝含量.对于高浊度水而言,具有适宜Al/Si摩尔比的PASC才具有良好的混凝效果,但对中、低浊度的地表水和含油废水而言,在实验的Al/Si摩尔比范围内,其值越小,混凝效果就越好.PASC在水体中的残留铝含量随着Al/Si摩尔比的降低和B值的升高而下降.PASC和PAC在中性pH条件下具有最低的残留铝含量.
聚硅氯化铝混凝剂的形态及带电特性研究  [PDF]
高宝玉,岳钦艳,李振东,王艳,于慧,王淑仁
环境科学 , 1998,
Abstract: 以AlCl3·6H2O、NaOH、盐酸和水玻璃为原料制备了不同碱化度(B)及不同Si/Al摩尔比的系列聚硅氯化铝混凝剂(PASC),采用Al-Ferron逐时络合比色法和微电泳技术研究了PASC中铝的水解产物形态分布及铝的水解沉淀物的带电特性,考察了B及Si/Al摩尔比对PASC中铝水解产物形态分布及带电特性的影响情况,并与聚合氯化铝(PAC)进行了比较。实验结果表明,B对PASC的形态分布有较大影响。Si/Al摩尔比对PASC的形态分布有一定的影响;B和Si/Al摩尔比影响PASC水解沉淀物的带电特性,随B升高及Si/Al摩尔比增大,PASC的零电位向低pH方向移动。
高浓度PASC复合混凝剂的混凝动力学研究  [PDF]
刘莉莉,周维芝,高宝玉,许鹏举,李倩
环境化学 , 2015,
Abstract: 以铝酸钠为碱化剂,合成了具有不同Si/Al摩尔比的聚硅氯化铝复合混凝剂(PASC),采用透光率脉动检测技术并结合混凝效能和Zeta电位的测定结果,对PASC以及聚合氯化铝(PAC)、参比PACref在混凝过程中絮集物形成和增长的变化差异作了对比研究.结果表明,混凝过程中,Zeta电位、剩余浊度以及混凝指数密切相关.采用铝酸钠为碱化剂合成并引入硅酸钠的混凝剂,有利于提高凝聚速度和絮集物颗粒大小.在Si/Al摩尔比为0.10时处理效果达到最佳.
Ferron Type of Coductivity in Metal CuFeSe2  [PDF]
A. M. Polubotko
Physics , 2011, DOI: 10.1134/S0031918X11060093
Abstract: It is pointed out, that the charge transfer in the compound in paramagnetic region has a ferron type of transport with ferrons of a small radius, predicted by N. Mott. For some another specimen the charge transfer may be carried out by ferrons of a large radius at very low temperatures. The results are well confirmed by the temperature dependence of resistivity and by metal type of the compound.
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