Preparation and characterization of organic polymer modified composite polyaluminum chloride

Compared with traditional aluminum salts, polyaluminum chloride （PACI） has better coagulation-flocculation performance in turbidity removal. However, it is still inferior to organic polymers in terms of bridging function. In order to improve the aggregating property of PACl, different composite PACl flocculants were prepared with various organic polymers. The effect of organic polymer on the distribution or Al（Ⅲ） species in composite flocculants was studied using ^27TAl NMR and Al-ferron complexation methods. The charge neutralization and surface adsorption characteristics of composite flocculants were also investigated. Jar tests were conducted to evaluate the turbidity removal efficacy of organic polymer modified composite flocculants. The study shows that cationic polymer and anionic polymer have significant influences on the coagulation-flocculation behaviors of PACl. Both cationic and anionic polymers can improve the turbidity removal performancc of PACl but the mechanisms arc much different： cationic organic polymer mainly increases the charge neutralization ability, but anionic polymer mainly enhances the bridging function.

Advances in controlled-release fertilizer encapsulated by organic-inorganic composite membranes

Heavy use of conventional fertilizers can lead to negative environmental concerns.Controlled-release fertilizers(CRFs)can effectively reduce the amounts of fertilizers used,improve the availability of fer-tilizers,and which is conducive to the protection of the ecological environment and sustainable devel-opment of agriculture.Therefore,it is imperative to develop and use CRFs as an alternative to traditional fertilizers.This review aims to present the classification,raw material composition,benefits,release process,release mode,and manufacturing methods of fertilizers coated with organic-inorganic com-posite membranes(OICMs)in order to provide an overall update and summarize CRFs encapsulated by OICMs and provide an insight for future trends in the field of fertilizers.It is expected that utilizing CRFs encapsulated by OICMs and their characteristics for agricultural applications can provide innovative ideas and suggestions for developing novel CRFs suitable for modern and sustainable agriculture.

Aqueous-Phase Sorption Behaviors of Cs⁺, Co²⁺, Sr²⁺and Cd²⁺ions on some Composite Ion Exchangers

A two new hybrid “organic-inorganic” composite ion exchangers (SAM and FAM), was synthesized by the combination of inorganic ion exchanger tin (IV) silicate and tin (IV) antimonate respectively with organic polymer polyacrylamide (PAm). The sorption isotherms for Cs+, Co2+, Sr2+ and Cd2+ ions on composite ion exchanger were investigated in the range (0.0005 - 0.01M) at different reaction temperature (30℃, 45℃ and 60℃ ± 1℃). The sorption data were subjected to different sorption isotherms and the results verified that Langmuir isotherm is the best model to be applied, and the monolayer sorption capacity were calculated and was found to increase as the reaction temperature increases.

Preparation and PerformanceAnalysis of Inorganic Polymer Flocculant PZFSiC

A new inorganic polymer flocculant-PZFSiC (zinc-iron-silicate polymer composite) is prepared by adding acid into a high modulus solution of water glass and introducing appropriate metallic ions(M) including Zn and Fe. The influence on flocculability of factors such as the mole ratios of M to SiO2,stirring time and pH are discussed .And the optimal preparing technical parameters are obtained by orthogonal tests. The optimum technical conditions of flocculation are determined. The result shows that when less PZFSiC is added into troubled water or waste water, turbidity removal can hit 98%, COD removal can exceed 93%. The water sample treated is clear and of good quality. These results also indicate that PZFSiC is a highly effective, nontoxic and benign to the enviroment.

Recent Advances and Progress for the Fabrication and Surface Modification of AIE-active Organic-inorganic Luminescent Composites

Organic dyes based hybrid organic-inorganic luminescent nanomaterials with high quantum efficiency, good physical or chemical stability, and favorable biocompatibility, have attracted growing attention recently because of their important applications in the areas of biomedical imaging, chemical sensors, and light-emitting diodes(LEDs). Nevertheless, conventional fluorescence molecules suffer from aggregation-caused quenching(ACQ) when they are doped into inorganic nanomaterials. Aggregation-induced emission(AIE) is an abnormal and intriguing fluorescent phenomenon that has aroused increasing interest for various applications especially in biomedical fields. Compared with conventional organic dyes, the AIE-active molecules will emit more intense fluorescence in their aggregates or solid states. It provides an elegant route to overcome the drawbacks of conventional organic molecules. Over the past few decades, the fabrication and surface modification of various organic-inorganic luminescent composites doped with AIE-active molecules have been reported. Therefore, it is highly desirable to summarize these advances. In this review, recent advances and progress in constructing various AIEgens-doped organic-inorganic hybrid nanocomposites and their subsequent surface modification were summarized. We hope this review could further promote the research of AIE-active functional materials.

Study and Application of a Novel Tap Water Flocculant

By using polyaluminum chloride (PAC), chitosan (CTS) and montmorillonite (MM) as the main raw materials, a novel tap water flocculant had been prepared. The optimal mass proportion of this flocculant was 1 g·L–1 chitosan:50 g·L–1 PAC:3g·L–1 MM = 30:11:7. Compared with the traditional polyaluminum chloride (PAC), the concentration of aluminum ion (Al3+) and suspended solids (SS) in the exit dropped 66.19% and 5.80% respectively, moreover, the cost was decreased by 9.95%. This flocculant was not only cheaper, but also provided improved flocculating function compared with traditional flocculant. The concentration of Al3+ in exit water was decreased greatly so the drinking water would be much safer.

Preparation and Application of an Low-Aluminium Tap Water Flocculant

A kind of environmental friendly novel composite flocculants which are used to treat raw water is prepared. It is made with chitosan (CS), iron modified polyaluminium chloride (CF-PAC) and modified montmorillonite on the principle of “the combination of organic and inorganic”. Under the optimum best compound formula and flocculation process, the turbidity of the waste water reduced by 0.62%, the chemical cost decreased by 12.43% and the content of aluminium ions dropped by 70.65%. There is an excellent characteristic and higher efficiency on the composite flocculant which can adsorb the organic matter in the water and chelate the heavy metal ions in the water.

PREPARATION AND PROPERTIES OF EXTRACELLULAR BIOPOLYMER FLOCCULANT

The biopolymer flocculant （named PS-2） producing by Pseudomonas fluorescens was investigated. The PS-2 had high efficiency with small dosage, when dealing with kaolin suspension, formed larger floc, with big sedimentation rate, over a wide range of temperatures. Distributing of flocculating activity test showed that the biopolymer flocculant was an extracellular product. The composition analysis of purified biopolymer flocculant showed that it composed mainly of polysaccharide and nucleic acid. The content of polysaccharide was 86. 7%, which determined by using phenol-vitriol method, and the content of nucleic acid was 7.8%, which determined by UV absorption method. The biopolymer flocculant as a powder form showed much better stability than that as a supernatant. The character of biopolymer flocculant was stable even it was heated to 100℃ when it in acidic condition. The optimal conditions to flocculate kaolin suspension were as follows： pH 8-12, flocculant dosage lmL/L, and Ca^2＋ as the optimal cation.

Optimal Evaluation of Coag-Flocculation Factors for Alum-Brewery Effluent System by Response Surface Methodology

This work investigates coag-flocculation optimization treatment of alum-brewery effluent system via response surface methodology (RSM). To minimize suspended and dissolved particles (SDP), experiments were carried out using nephelometric jar test and 23-factorial design with three star-points, six-center-points and two replications. A central composite design, which is the standard design of RSM, was used to evaluate the effects and interactions of three major factors (coagulation pH, coagulant dosage, settling time) on the treatment efficiency. Multivariable quadratic model developed for the response studied indicates the optimum conditions to be 9, 500mg/l and 20minutes for coagulation pH, coagulant dosage and settling time, respectively. At optimum, the SDP was reduced from 10831.490mg/l to 801.451mg/l, representing 92.601% removal efficiency. RSM has demonstrated to be appropriate approach for the optimization of the coag-flocculation process by statistical evaluation.

磁性聚硅酸铝镁-淀粉絮凝剂处理刚果红模拟废水

采用Fe_(3)O_(4)、硅酸钠、Al_(2)(SO_(4))_(3)、MgSO_(4)、淀粉(St)制备了磁性聚硅酸铝镁(PSAM)-St絮凝剂(Fe_(3)O_(4)-PSAM-St),通过FTIR,XRD,SEM,VSM,TEM等技术对Fe_(3)O_(4)-PSAM-St的结构进行了表征,研究了Fe_(3)O_(4)-PSAM-St的制备条件及絮凝条件对模拟废水中刚果红去除效果的影响。表征结果显示,该絮凝剂是一种新型磁性聚硅酸复合材料。实验结果表明:Fe_(3)O_(4)-PSAM-St的最佳制备条件为pH=3、n(Mg)∶n(Al)=2∶8、m(St)∶m(Si)=0.6;当Fe_(3)O_(4)-PSAM-St加入量为40 mg/L、模拟废水p H为5~12、絮凝时间为10 min、沉降时间为10 min时,刚果红去除率最高可达95.0%;储存3个月后,Fe_(3)O_(4)-PSAM-St的絮凝性能基本保持不变;以50%(w)絮凝后的磁性絮体和50%(w)Fe_(3)O_(4)-PSAM-St为絮凝剂,重复进行6次絮凝实验后,刚果红去除率仍可达93%左右。

自重及加载条件下絮凝剂调理废弃泥浆的脱水效果

群桩基础、地下连续墙等施工会带来巨量的废弃泥浆,城市地下空间开发利用及盾构掘进过程会产生大量高含水率泥浆状的渣土,常规的堆场处理受限于成本和环境问题,需要对废弃泥浆进行高效脱水处理,减少废弃泥浆量。为研究絮凝剂调理废弃泥浆的脱水效果,提升泥浆脱水效率,采用单一、复合絮凝剂调理废弃泥浆,通过室内量筒沉积和小型堆载预压试验,对比研究絮凝剂类型和掺量配比对泥浆泥水分离效果的影响,并为脱水效果提供判断依据。结果表明:有机絮凝剂能够改善泥浆的脱水性能,提高泥水分离程度,且存在最优掺量;复合絮凝剂能够发挥有机、无机絮凝剂的协同作用,更进一步提升泥浆脱水程度,其中PAM类复合絮凝剂脱水性能优异,PAM与CaO复合絮凝剂组合处理泥浆时,其沉积层含水率降低程度能够达到82.75%。研究成果可为废弃泥浆的合理处置和资源化利用提供参考。

Effect of viscosity,basicity and organic content of composite flocculant on the decolorization performance and mechanism for reactive dyeing wastewater

A coagulation/flocculation process using the composite flocculant polyaluminum chloride-epichlorohydrin dimethylamine （PAC- EPI-DMA） was employed for the treatment of an anionic azo dye （Reactive Brilliant Red K-2BP dye）. The effect of viscosity 01）, basicity （B = [OH]/[Al]） and organic content （Wp） on the flocculation performance as well as the mechanism of PAC-EPI-DMA flocculant were investigated. The η was the key factor affecting the dye removal efficiency of PAC-EPI-DMA. PAC-EPI-DMA with an intermediate η （2400 mPa.sec） gave higher decolorization efficiency by adsorption bridging and charge neutralization due to the co-effect of PAC and EPI-DMA polymers. The Wp of the composite flocculant was a minor important factor for the flocculation. The adsorption bridging of PAC-EPI-DMA with η of 300 or 4300 mPa.sec played an important role with the increase of Wp, whereas the charge neutralization of them was weaker with the increase of Wp. There was interaction between Wp and B on the removal of reactive dye. The composite flocculant with intermediate viscosity and organic content was effective for the treatment of reactive dyeing wastewater, which could achieve high reactive dye removal efficiency with low organic dosage.

A Transparent Photoresist Made of Titanium Dioxide Nanoparticle-Embedded Acrylic Resin with a Tunable Refractive Index for UV-Imprint Lithography

Transparent photoresists with a high refractive index(RI)and high transmittance in visible wavelengths have promising functionalities in optical fields.This work reports a kind of tunable optical material composed of titanium dioxide nanoparticles embedded in acrylic resin with a high RI for ultraviolet(UV)-imprint lithography.The hybrid film exhibits a tunable RI of up to 1.67(589 nm)after being cured by UV light,while maintaining both a high transparency of over 98%in the visible light range and a low haze of less than 0.05%.The precision machining of optical microstructures can be imprinted easily and efficiently using the hybrid resin,which acts as a light guide plate(LGP)to guide the light from the side to the top in order to conserve the energy of the display device.These preliminary studies based on both laboratory and commercial experiments pave the way for exploiting the unparalleled optical properties of nanocomposite resins and promoting their industrial application.

In-situ construction of grass-like hybrid architecture responsible for extraordinary corrosion performance: Experimental and theoretical approach

Despite the engineering potential by the co-existence of inorganic and organic substances to protect vulnerable metallic materials from corrosive environments,both their interaction and in-situ formation mechanism to induce the nature-inspired composite remained less understood.The present work used three distinctive mercaptobenzazole(MB)compounds working as corrosion inhibitors,such as 2-mercaptobenzoxazole(MBO),2-mercaptobenzothiazole(MBT),and 2-mercaptobenzimidazole(MBI)in a bid to understand how the geometrical structure arising from O,S,and N atoms affected the interaction toward inorganic layer.MB compounds that were used here to control the corrosion kinetics would be interacted readily with the pre-existing MgO layer fabricated by plasma electrolysis.This phenomenon triggered the nucleation of the root network since MB compounds were seen to be adsorbed actively on the defective surface through the active sites in MB compound.Then,the molecule with twin donor atoms adjacent to the mercapto-sites affected the facile growth of the grass-like structures with‘uniform’distribution via molecular self-assembly,which showed better corrosion performance than those with having dissimilar donor atoms with the inhibition efficiency(η)of 97%approximately.The formation mechanism underlying nucleation and growth behavior of MB molecule was discussed concerning the theoretical calculation of density functional theory.

污水处理装置排放超标控制措施研究

针对目标污水处理装置采用加药絮凝的方式对污水进行处理,出现了出口系统水质污染物排放超标的现象,在分析进水系统和出水系统水样水质指标的基础上,考察了不同类型絮凝剂对污水处理效果的影响,优选出性能较好的复合絮凝剂FX-1,并考察了污水处理装置的长时间运行效果。结果表明:FX-1的使用能够有效降低目标污水处理装置出口端水样中的各项污染物浓度,且出水系统水样各项污染物浓度在12个月内均能得到有效控制,COD、悬浮物、氨氮、总氮、总磷和石油类含量均能达到GB 18918—2002中“一级A标准”要求,实现了目标污水处理装置高效稳定运行。

复合高分子絮凝剂对工业含铊废水处理的影响因素分析与优化

本文旨在开发一种新型的复合高分子絮凝剂,用于有效处理含铊工业废水。通过粉煤灰和金属废料制备出聚硅酸铝铁溶液,再与二甲基二烯丙基氯化铵(DMDAAC)混合,制备出该复合高分子絮凝剂。通过单一正交实验方法,探讨了不同搅拌时间、反应温度、絮凝剂投加量等因素对絮凝效果的影响。结果显示,该絮凝剂能显著降低含铊废水中铊的含量,具有较好的处理效果。本研究不仅为含铊废水的处理提供了新的思路,也为环境保护和资源再利用提供了技术支持。

复合高分子絮凝剂的制备及研究进展

复合高分子絮凝剂近年来发展迅速并成为研究的热点。对无机复合高分子絮凝剂、有机复合高分子絮凝剂和无机-有机复合高分子絮凝剂的国内外研究现状进行了概述,分析了复合高分子絮凝剂处理废水的优势及其发展面临的问题,指出无机-天然有机复合高分子絮凝剂将是未来研究的重点。

壳聚糖复合絮凝剂在城市生活污水处理中的应用

研究了壳聚糖复合絮凝剂在不同来源的城市生活污水处理中的应用 ,确定了壳聚糖复合絮凝剂在城市生活污水处理中的最佳投加量 ,即 :最佳投加量 (mg·l- 1)∶原水COD (mg·l- 1) =1∶8 2— 8 7和最佳pH =7;它与传统的絮凝剂PAC同比 ,COD去除率提高 7— 1 3% ,SS去除率提高 3— 1 0 % ,[Al3 + ]下降 6 1— 85 % ,药剂加量减少76— 82 % .

壳聚糖絮凝剂处理水源水中有机物的试验研究

研究了壳聚糖絮凝剂的絮凝特性,进行了壳聚糖絮凝剂跟无机絮凝剂复合絮凝对水源水中浊度和有机物去除的试验。实验结果表明,复合絮凝能够相互促进各自的絮凝性能,显著提高有机物的去除效果,并使除浊和去除有机物得到了统一。在壳聚糖絮凝剂分别与三种常用无机絮凝剂(硫酸铝、氯化铁和聚合铝铁)的复合絮凝的效果的实验表明,其中聚合铝铁跟壳聚糖的复合絮凝剂的效果最好,在最佳条件下,其浊度、CODMn和UV254的去除率分别达到了97%、44%和55%。

无机高分子复合絮凝剂PFSS的制备与性能研究

研究了无机高分子复合絮凝剂聚硅硫酸铁 (PFSS)的制备与絮凝性能。通过对SiO2 的质量分数、铁硅量比、PFSS的 pH值、硅酸活化时间等因素的调整和控制 ,制备出性能优异的絮凝剂。研究结果表明 :w(SiO2 ) =1 4 %～ 2 0 % ,n(Fe)∶n(Si) =(0 8～ 1 0 )∶1 0 ,PFSS的pH =1 5～ 1 8,硅酸活化时间 1～ 18h时 ,可获得絮凝性能优异的无机高分子复合絮凝剂。将制备的絮凝剂用于实际废水样品处理 ,其除浊效果明显优于目前常用的絮凝剂PAC、PFS、FeCl3 、Fe2(SO4) 3 。