Properties of polyferric-silicate-sulfate(PFSS) coagulant

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聚硅硫酸铁絮凝剂的研制及性能研究

以Fe2(SO4)3,H2SO4和Na2SiO3为原料,采用复合共聚生产工艺,制备了聚合硅酸硫酸铁（PFSS）絮凝剂。研究了SiO2含量、Fe^3 /SiO2摩尔比、pH值等因素对硅酸聚合和PFSS稳定性的影响。正交试验结果表明,当SiO2含量为2.0%,Fe^3|/SiO2洋比为1．0时,PFSS具有最佳混凝效果,较宽的pH范围和保持期。与聚合氯化铝（PAC）进行了性能对比试验。结果表明,PFSS比PAC具有更好的去浊、脱色、除油的效果和残留硅、铁量少的特点。     

聚硅酸硫酸铁絮凝剂的制备及应用

制备了不同 Fe/Si含量比的聚硅酸硫酸铁 (PSFS)。比较了不同 Fe/Si的 PSFS的絮凝效果及稳定性 ,实验了 p H值及絮凝剂用量对絮凝效果的影响。研究表明 ,当 p H=3左右 ,Fe/Si含量比为 1∶ 2时制备的PSFS具有较好的絮凝效果。在实验条件下 ,絮凝剂的最佳用量为 8mg/L。     

高浓度聚合氯化铁(PFC)中铁的形态分布与转化研究

以氯化铁和无水碳酸钠为原料,加入稳定剂W,采用共聚工艺,制备了稳定高浓度的聚合氯化铁(PFC)混凝剂.采用Fe-Ferron逐时络合比色法研究了PFC中铁的形态分布情况,考察了熟化时间、碱化度(B)及n(W)/n(Fe)(W/Fe摩尔比)对PFC中铁的形态分布的影响.研究结果表明,在PFC中,由于稳定剂W与铁的水解产物间的相互作用,使得铁的水解聚合形态分布及转化情况发生了变化.碱化度(B)、n(W)/n(Fe)和熟化时间均对铁的形态分布有重要的影响.      

活性硅酸聚合硫酸铁的研究

以硅酸钠，硫酸和聚合硫酸铁为原料制备活性硅酸合硫酸铁，测定了ＡＳＰＦＳ红外光谱，了Ｆｅ／Ｓｉ摩尔比和水样ＰＨ值等因素对产品和除浊效果的影响当Ｆｅ／Ｓｉ摩尔比为１．５时产品稳定性和除浊效果均较好。     

聚硅酸金属盐复合絮凝剂形貌结构及性能研究

以硅酸钠、硫酸和硫酸盐为原料制备聚硅酸金属盐(PSMS)复合絮凝剂,通过红外光谱研究了金属元素与聚硅酸(PS)的相互作用情况,采用电子显微镜观察了PS、PSMS和相应简单金属盐(MS)的形貌,利用激光粒度分析仪分析了絮体粒径变化及破碎与恢复情况,并考察了PSMS在不同投加量下处理腐植酸模拟废水的效果。结果表明:PSMS的红外光谱图中有M—O—Si振动峰出现,扫描电镜显示PSMS的聚集单元表面异于PS的平滑,为细小不规整的晶体颗粒,并与相应硫酸盐(MS)形貌有一定关联。此外,无论是所形成絮体的粒径还是对腐植酸的去除效果,聚硅酸硫酸铝(PSAlS)和聚硅酸硫酸铁(PSFeS)均优于其它聚硅酸金属盐,PSFeS的絮体虽易破碎但破碎后恢复能力最好,且粒径最大而容易沉降。     

聚合硅酸铝铁絮凝剂中铁的形态分布与转化

以AlCl₃·6H₂O ,FeCl₃·6H₂O ,Na₂CO₃,盐酸和硅酸钠为原料制备了不同碱化度B及不同n(Al)∶n(Fe)∶n(Si)摩尔比的系列聚合硅酸铝铁絮凝剂 (PAFSC) ,采用Fe -Ferron逐时络合比色法研究了PAFSC中铁的形态分布情况 ,考察了熟化时间、制备工艺及n(Al)∶n(Fe)∶n(Si)对PAFSC中铁的形态分布的影响情况。研究结果表明 :随着熟化时间的延长 ,铁和聚硅酸摩尔数的增加 ,PAFSC中铁的形态由低聚物向高聚物转化.      

以TEOS为硅源的聚硅氯化铝中铝及硅形态分布

以正硅酸乙酯 (TEOS)为硅源 ,合成了新型的聚硅氯化铝 (PASC) ,利用Al Ferron逐时络合比色法和Si Mo逐时络合比色法分别研究了其Al形态及Si形态分布 ,并与常规方法 (以硅酸钠为硅源 )合成的聚硅氯化铝做了比较 .实验结果表明 ,新方法合成的PASC具有铝硅分布均匀 ,分子量较大 ,产品重现性好的优点 .两种方法合成的PASC具有相同的Al形态分布规律 ,即高分子量Al形态含量随B值 (碱化度 )和Si Al摩尔比的增大而增加 ,Al形态随Si Al摩尔比的变化程度随B值的增大而增大 .另外通过新方法发现 ,Si形态分布也具有规律性并和Al形态具有相似的分布特征 ,但Si形态随Si Al摩尔比的变化程度随B值的增大而减小 .     

PFS-PS硅铁絮凝剂的合成形态及应用研究

实验采用活化硅酸 ,自制聚合硫酸铁为原料 ,在不同碱化度和Si/Fe摩尔比条件下 ,制备出聚合硅酸硫酸铁 (PFS PS)无机高分子絮凝剂。考察影响产品稳定性的因素 ,分析了产品Fe(Ⅲ ) ,Si(Ⅳ )的形态分布特征。并以炼油厂浮渣为处理对象 ,对影响硅铁絮凝剂絮凝性能的合成因素进行了考察。     

聚合铝形态分布特征及转化规律

采用多种实验方法,对Al(Ⅲ)的水解—聚合—沉淀反应特征及其转化规律、形态分布及规范分子量大小进行了研究,同时应用X-射线衍射光谱仪和红外光谱仪对聚合铝形态进行了表征。由研究结果似可推断,Al(Ⅲ)水解—聚合过程的形态转化过程为线型→环型→体型。其聚合形态分布取决于翔/铝比值或pH值以及其它因素。在一定羟/铝比值时,聚合铝溶液中可划分为三种类型的形态分布。提出了相应的形态转化模式来表达聚合铝的形态及转化规律。     

硫铁矿烧渣制备PFS、PFPS及其除浊效果比较

以硫铁矿烧渣为原料，采用胶体分散法新工艺制备得到聚合硫酸铁（PFS），然后在PFS溶液中加入磷酸钠得到聚磷硫酸铁（PFPS）。研究了影响PFPS盐基度的因素，以及PFS、PFPS的除浊效果。结果表明，采用胶体分散法制备PFS的工艺独特，无污染物氮氧化物的产生。实验还表明，PFPS的絮凝效果明显好于PFS。PFPS投放量以及盐基度适宜时可达到最佳除浊效果。     

从铝形态转化角度分析AlCl3的混凝性能

应用Ferron逐时络合比色法,从铝形态转化角度对AlCl₃混凝性能进行了研究. 结果表明,AlCl₃的混凝性能与其发生二次水解反应后水解产物形态中的Al_b所占比例成正比,而影响AlCl₃水解产物中Al_b所占比例的主要因素是体系中的pH. 混凝过程中的水系组成及浓度和AlCl₃投加量的不同均会引起体系pH变化,从而影响AlCl₃水解产物中Al_b所占比例,最终影响AlCl₃的混凝效果.AlCl₃在混凝过程中所表现出的水解程度大、产生H+多的特征,使其在高碱度体系和高浓度有机酸体系的污水处理中效率更高.      

新型絮凝剂PPFS的制备及其絮凝性能研究

 基于固体聚硫酸铁（PFS）的制备方法,研究了固体聚磷硫酸铁-PPFS-的实验室制法,并对比了PPFS、PAS-聚硫酸铝-、PFS对Cu²⁺、COD_Mn的去除性能.结果表明,在制备条件下,P/Fe 为0.3:1的PPFS溶解性好,对Cu²⁺、COD_Mn的去除率明显优于PFS、PAS;P/Fe为0.4:1的PPFS 总Fe量、碱度及对Cu²⁺、COD_Mn的去除率均低于P/Fe为0.3:1的PPFS.     

聚硅氯化铝混凝剂的形态及带电特性研究

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     

Chemical species distribution and transformation in polyaluminum chemical solutions

The hydrolysis polymerization precipitation process of Al(III) was studied with pH titration method, and the prepared polyaluminum solutions were characterized by various experimental methods: acid depolymerization, timed complex-colorimetric procedure, ultrafiltration, X-ray diffraction and infrared absorption spectrum. The results showed that the chemical species transformation and distribution of Al(III) in the hydrolysis-polymerization process depended on B=(OH/Al) ratio, pH and other factors. By their structures, the chemical species can be divided into three categories of monomeric (Ala), polymeric (Alb), sol or gel precipitates (Alc) and the polymeric species may be further divided into three groups such as linear low polymer (Alb1), linear high polymer (Alb2) and high polymer with cyclic structure (Alb3). The nominal molecular weight of polymeric species obtained by ultrafiltration was about 1000-50000 and most of them failed into a range around 10000. A scheme for the chemical speciation model     

聚硅酸铁(PSF)混凝剂硅铁反应过程研究

以水玻璃、硫酸亚铁及氯酸钠为原料,用共聚法制备不同Si/Fe比的聚硅酸铁(PSF)混凝剂(PSF0.5、PSF1、PSF3分别指Si/Fe摩尔比为0.5、1、3),同时监测制备过程中pH的变化,并就不同共聚反应时间的样品,分别采用X-射线衍射法(XRD)、紫外吸收(UVA)扫描法、透射电镜法(TEM)、光子相关光谱法(PCS)及红外光谱法(IR)对其反应过程的微观品质进行多方面表征.结果表明,PSF是硅铁反应的共聚物,而不是简单的原料复配.不同Si/Fe比的PSF具有不同的硅铁成键速度、成键方式及成键稳定性,低Si/Fe比主要生成以Si—O—Fe—O—Fe—O—Si键络合的物种,而高Si/Fe比主要生成以Si—O—Fe—O—Si—O—Si键络合的物种,Fe—O—Fe键的形成速度快并且与Si—O—Fe键的形成可能有相互促进作用,而Si—O—Si键(硅酸聚合)形成速度慢并且与Si—O—Fe键的形成可能有相互阻碍作用,Fe—O—Fe键的稳定性比Si—O—Fe或Si—O—Si键差.对于PSF中硅铁不同成键模式的分析为合成高性能、高稳定性的硅酸铁类混凝剂以及为优势形态控制提供了一定的理论基础.     

Removal of total cyanide in coking wastewater during a coagulation process：Significance of organic polymers

Whether a cationic organic polymer can remove more total cyanide （TCN） than a non-ionic organic polymer during the same flocculation system has not been reported previously. In this study, the effects of organic polymers with different charge density on the removal mechanisms of TCN in coking wastewater are investigated by polyferric sulfate （PFS） with a cationic organic polymer （PFS-C） or a non-ionic polymer （PFS-N）. The coagulation experiments results show that residual concentrations of TCN （Fe（CN）6^3-） after PFS-C flocculation （TCN 〈 0.2 mg/L） are much lower than that after PFS-N precipitation. This can be attributed to the different TCN removal mechanisms of the individual organic polymers. To investigate the roles of organic polymers, physical and structural characteristics of the floes are analyzed by FT-IR, XPS, TEM and XRD. Owing to the presence of N＋ in PFS-C, Fe（CN）3- and negative flocs （Fe（CN）63- adsorbed on ferric hydroxides） can be removed via charge neutralization and electrostatic patch flocculation by the cationic organic polymer. However, non-ionic N in PFS-N barely reacts with cyanides through sweeping or bridging, which indicates that the non-ionic polymer has little influence on TCN removal.     

聚硅酸硫酸铁强化混凝去除微污染水源水中天然有机污染物

应用强化混凝技术,降低原水中有机物含量,是控制消毒副产物生成的有效途径之一。通过混凝搅拌试验,评价了聚硅酸硫酸铁混凝剂对原水中有机污染物的去除效果,考察了混凝剂投加量、pH值等对去除效果的影响。结果表明：聚硅酸硫酸铁去除有机物和除浊能力明显优于硫酸铁、聚合硫酸铁,其适宜的投药量范围和pH值范围宽;聚硅酸硫酸铁在混凝过程中形成的矾花较大,沉降速度快,因而可缩短处理水在构筑物中的停留时间,提高系统的处理能力;此外,通过正交实验确定了聚硅酸硫酸铁混凝剂的最佳水力条件。     

Preparation and coagulation efficiency of polyaluminium ferric silicate chloride composite coagulant from wastewater of high-purity graphite production

The aim of the present work was to produce a polyaluminium ferric silicate chloride (PAFSiC) coagulant from acidic and alkaline wastewater of purifying graphite by roasting, and subsequently to evaluate coagulation efficiency of the reagent by treating surface water from the Yellow River as well as municipal wastewater in comparison with the conventional coagulant polyaluminium chloride (PAC). The PAFSiC coagulant was prepared by co-polymerization. The effects of (Al+Fe)/Si molar ratio, OH/(Al+Fe) molar ratio (i.e., value), coagulant dosage and pH value of test suspension on the coagulation behavior of FAFSiC and the stability of the PAFSiC were also examined. Results showed that PAFSiC performed more efficiently than PAC in removing turbidity, chemical oxygen demand (COD), and total phosphate (TP). The PAFSiC with a value of 2.0 and (Al+Fe)/Si ratio of 5 (PAFSiC 2.0/5) showed excellent coagulation effect for both turbidity and COD, while PAFSiC 1.0/5 was the best for TP. The optimum coagulation pH range of PAFSiC 2.0/5 was 5.0–9.0, slightly wider than that of PAC (6.0–8.0). The process can be easily incorporated into high-purity graphite production plants, thereby reducing wastewater pollution and producing a valuable coagulant.     

Reaction mode between Si and Fe and evaluation of optimal species in poly-silicic-ferric coagulant

A kind of Fe-polysilicate polymer, poly-silicic-ferric （PSF） coagulant was prepared by co-polymerization （hydroxylation of mixture of Fe^3＋ and fresh polysilicic acid （PS））, in which PSF0.5, PSF1 or PSF3 denotes Si/Fe molar ratio of 0.5, 1 or 3, respectively. The effects of Si/Fe ratio and reaction time （co-polymerization time or aging time） on the reaction mode between Si and Fe were studies, and the optimal species of PSF was evaluated by pH change during the preparation of PSF and coagulation tests. The results showed that the characteristics of PSF are largely affected by both reaction time and Si/Fe ratio. PSF is found to be a essential complex of Si, Fe, and many other ions. The reaction mode between Si and Fe differs with various Si/Fe ratios. The pH of PSF0.5, PSF1 or PSF3 tended to be stable when reaction time is 10, 25 or 55 rain, respectively, which is almost consistent with the time reaching the relative stable morphology that is just the optimal species of higher coagulation efficiency. The optimal reaction time reaching optimal species can be evaluated by measuring the pH change during the polymerization process.