【作者】 尚宏周；

【导师】 郑玉斌；

【作者基本信息】 大连理工大学 ， 高分子材料， 2009， 博士

【摘要】 在染料和印染废水脱色处理中,絮凝沉降法是当前国内外重点研究的方向之一,而絮凝脱色法的效果关键取决于絮凝剂的性能。近年来,随着絮凝理论和化学工业的发展,水处理絮凝剂在我国发展十分迅速。絮凝剂从无机低分子到有机高分子,从功能单一型到多功能型,从单独使用到复配使用,形成了品种系列化、功能多样化、使用成本经济化等特点,引起了科研和水处理工业的广泛关注。近年来的研究认为,阳离子型有机高分子絮凝剂由于其分子链段上带有正电荷基团,对废水或污水中带有负电荷的有机物质具有较好的去除效果,特别是对毒害性较大、难于脱除的染料分子具有较好的絮凝效果。在研究中发现,阳离子絮凝剂具有脱色效果好、适用范围广、受pH影响小、用量少、絮凝速度快等特点,所以,目前国内外积极研发新型高效的阳离子型有机高分子絮凝剂。丙烯酰胺类阳离子絮凝剂无疑是研究最多的品种。目前聚合所用的阳离子单体主要依赖进口,成本较高,而絮凝剂分子中阳离子密度较低时,对染料脱色效果又很不理想,为了解决生产成本和絮凝能力之间的矛盾,本论文在保持阳离子度较低的条件下,对目前流行的阳离子型高分子絮凝剂进行了疏水改性。通过在分子结构中引入功能型基团,增强絮凝剂分子和有机物分子之间的相互作用,降低絮凝剂分子和絮体的水溶性,从而使染料分子快速地从水中分离出来,提高阳离子型絮凝剂的絮凝效果。论文首先以丙烯酰胺(AM)和二烯丙基二甲基氯化铵(DADMAC)为共聚单体,利用反相乳液聚合法合成了共聚物P(AM-DADMAC),考察了复合乳化剂、分散介质、引发剂种类、油水体积比、引发剂浓度、单体浓度等因素对乳液稳定性和共聚物特性粘度的影响,确定了较理想的反相乳液体系。在此基础上,以煤油为分散介质、Va-044为引发剂,Span80/Tween80为复合乳化剂、乙烯基三甲氧基硅烷(VTMS)为疏水改性单体、丙烯酰胺(AM)和二甲基二烯丙基三甲基氯化铵(DADMAC)为主要共聚单体进行三元共聚,利用反相乳液聚合法制备了疏水改性阳离子型絮凝剂P(AM-DADMAC-VTMS),克服了水溶液聚合的不足。考察了VTMS和DADMAC单体投料率对产物性能的影响。利用红外谱图(FT-IR)证实了三元共聚物的结构。利用扫描电镜(SEM)对乳液中颗粒和聚合固体粉末进行了形貌观察。利用合成的P(AM-DADMAC-VTMS)对活性艳红X-3B进行了脱色研究,结果表明,随着VTMS含量的增加,改性絮凝剂的脱色能力提高,当共聚摩尔比为AM/DADMAC/VTMS=79.2/19.8/1.0时,最大脱色率为94.24%;随着DADMAC含量的增加,改性絮凝剂的最佳剂量降低,但脱色率也降低;改性絮凝剂最佳的pH使用范围为2-5,VTMS含量越高,脱色率受pH的影响越小;P(AM-DADMAC-VTMS)的脱色效果随NaCl浓度的增加而下降,但随VTMS含量的增高,脱色率受NaCl浓度的影响减小。甲基丙烯酰氧乙基三甲基氯化铵(DMC)也是常用的阳离子聚合单体,因此我们以AM、DMC和VTMS为共聚单体,通过反相乳液聚合法制备了疏水改性阳离子聚丙烯酰胺P(AM-DMC-VTMS)。通过对活性艳红X-3B的脱色研究发现:在DMC投料率相近的条件下,P(AM-DMC-VTMS)的脱色能力优于P(AM-DMC),且随着VTMS含量的增加,活性染料的脱色率提高;随着DMC含量的增加,P(AM-DMC-VTMS)脱色能力提高;最佳pH使用范围为2-5;VTMS含量越高,脱色率受pH影响越小,脱色率受NaCl浓度的影响越小。对分散橙30的脱色研究显示,VTMS的引入大大提高了絮凝剂对分散染料的去除能力,且随着VTMS的增加,最佳脱色率增加。当共聚摩尔比为AM/DMC/VTMS=79.2/19.8/1.0时,共聚物对活性艳红X-3B的最大脱色率为89.3%,对分散橙30的最大脱色率为98.1%,而P(AM-DMC)在共聚摩尔比AM/DMC=80/20时,对活性艳红X-3B的最大脱色率为41.7%,对分散橙30的最大脱色率为46.9%。为进一步研究疏水单体对染料废水脱色的影响,选择了甲基丙烯酰氧丙基三甲氧基硅烷(MPMS)作为疏水改性单体,以AM,DMC为主要聚合单体,制备了P(AM-DMC-MPMS)。P(AM-DMC-MPMS)的水溶性略差于P(AM-DMC-VTMS),对活性艳红M-8B有较好的脱色效果,当共聚摩尔比为AM/DMC/MPMS=79.2/19.8/1.0,最佳剂量为180mg/L时,染料分子被完全脱除;阳离子度增加,最佳剂量减小。在对分散染料、高岭土悬浮液的絮凝实验中,P(AM-DMC-MPMS)的絮凝效果均优于P(AM-DMC)。对实际染织废水脱色时,P(AM-DMC-MPMS)的脱色能力优于PFS。P(AM-DMC-MPMS)对M-8B的脱色机理表明,染料分子的脱除是靠电性中和、疏水相互作用和分子间氢键共同作用完成的。在阳离子度相对较低时,分子间氢键和疏水相互作用是染料脱色的最关键因素。P(AM-DMC-MPMS)/PFS是复合相容体系,能够形成互相穿插的网状结构。对M-8B和分散橙染料废水进行脱色研究,结果显示:最佳剂量分别为15.45mg/L和30.9mg/L,脱色率分别为99.8%和99.39%;最佳pH使用范围为3-6。对实际染织废水脱色时,P(AM-DMC-MPMS)/PFS的脱色效果优于PFS,P(AM-DMC-MPMS)/PFS在最佳剂量为55.68mg/L,最大脱色率为82.57%,而PFS在74.24mg/L时,脱色率也只有59.52%。更多还原

【Abstract】 The removal of dye and dissolved organic matter by flocculation is one of important research areas in textile wastewater treatments.The color removal efficiency mainly depends on the properties of flocculants.In recent year,flocculants develop rapidly along with the development of the flocculants’ theory and chemical industry.Various flocculants categories have been developed including inorganic flocculants,organic flocculants,low molecular weight flocculants,organic polymer flocculants and composite flocculants.Wide attention has been drawn in science research and water-treatment industry.Due to positive charge in molecular chain,cationic organic-polymer flocculants can remove organics with negative charge efficiently from waste-water,especially,dye wastewater,which is toxical and hard to remove from water.It has been found that cationic flocculants have the advantages that high decolorization efficiency,wide application areas, small pH effect,low dosage and quick flocculation speed,etc.Therefore,cationic organic-polymer flocculants have been extensively studied and applied to waste-water treatment in the world.Cationic polycarylamide is one of most popular flocculants.At present, cationic monomers used to polymerize mainly depend on import,so that cost is high.In order to solve the contradiction between cost and flocculability,popular cationic-polymer flocculants were hydrophobically modified by introducing functional groups into flocculants molecular chain in this paper.This enhanced the intermolecular interaction between flocculant and dye,reduced water-solubility of floccutant and floes.And so floes dye molecules were removed from water quickly and flocculation efficiency rose.Firstly,P(AM-DADMAC) was synthesized in inverse emulsion.The effects of composite emulsifier、disperse medium,kind of initiator,volume ratio of oil and water、concentration of initiator and monomer on stability of inverse emulsion and intrinsic viscosity of copolymer.The suitable polymeric system was chosen by studying the polymerization of AM and DADMAC in inverse emulsion.On the basis,a flocculant of P(AM-DADMAC-VTMS) was synthesized in inverse emulsion,with kerosene as disperse phase,Va-044 as an initiator,Span80/Tween80 as composite emulsifier,VTMS as a hydrophobically modified monomer,AM and DADMAC as main comonomers,overcoming the shortage of aqueous solution polymerization.The effects of feed ratio of VTMS and DADMAC on characteristics of polymer were investigated.The structure of terpolymer is confirmed by FT-IR.Particles in inverse emulsion and polymer powders were investigated by the scanning electronic microscopy(SEM).The color removal of reactive brilliant red X-3B (X-3B) by P(AM-DADMAC-VTMS) has been studied.The results showed that removal ratio of X-3B increased largely with increasing the content of VMS,and when AM/DADMAC/VTMS=79.2/19.8/1.0,the largest removal ratio is 94.28%;optimal dose and removal ratio decrease with DADMAC increase;modified flocculant has better flocculability when pH is 2-5;the addition of NaCI to waste-water shield the function of charge neutralization between flocculant and dye,but the more the content of VTMS is,the less the effects ofpH and NaC1 on color removal are.Methacryloxyethyltrimethyl ammonium chloride(DMC) is also a typical cationic monomer used to synthesize cationic flocculant.Therefore,the paper synthesized a novel flocculant P(AM-DMC-VTMS),with DMC、AM and VTMS as comonomerso The color removal of X-3B and dispersion orange 30 were investigated by P(AM-DMC-VTMS).It is found that the decolorization efficiency of P(AM-DMC-VTMS) is better than that of P (AM-DMC).With the content of VTMS increase,removal ratio of reactive dye and dispersion dye increase.With the content of DMC,removal ratio of reactive dye increase. Optimal pH ranges is 2-5.When molar ratio of trepolymer is AM/DMC/VTMS=79.2/19.8/1.0, maximum decolorization of X—3B is 89.3%and that of dispersion organe 30 is 98.1%. While P(AM-DMC) with similar molar ratio,maximum decolorization is only 41.7%and 46.9%for X-3B and dispersion organe 30,respectively.In order to further study the effect of hydrophobically modified monomer on decolorization,the paper choose another monomer-methacryloxypropyltrimethoxy silane (MPMS) as a modified agent and synthesized a novel flocculation P(AM-DMC-MPMS). Water-solubility of P(AM-DMC-MPMS) is lower than that of P(AM-DMC-VTMS).when molar ratio of terpolymer is AM/DMC/MPMS=79.2/19.8/1.0,optimal dose is 180mg/L and M-8B was removed completely.With the content of DMC increase,optimal dose decreases. P(AM-DMC-VTMS) is better efficiency than P(AM-DMC) as flocculant to treat waste-water of dispersion dye and suspension of kaolin.The study on the decolorization of printing and dyeing wastewater showed that decolorizing performance of P(AM-DMC-MPMS) is better than that of PFS.Decolorization mechanism showed that dye molecules removal of M-8B depend on the cooperation of charge neutralization、hydrophobic interaction and intermolecular hydrogen bond.Intermolecular hydrogen bond and hydrophobic interaction are key factors of decolorization when their cationicity are low.P(AM-DMC-MPMS)/PFS is compatible system and can form network structure.The color removal of M-8B and dispersion organ 30 by composite flocculant was investigated. Removal ratio of M-8B by P(AM-DMC-MPMS)/PFS and P(AM-DMC)/PFS is 99.8%and 99.39%,respectively,and for dispersion organ 30,removal ratios are both above 98%when pH is 3-6.P(AM-DMC-MPMS)/PFS have more efficiency than PFS when as flocculation for printing and dyeing waste-water.Optimal dose and removal ratio of the former are 55.68mg/L and 82.57%,respectively.However,for the latter,when dose is 74.24mg/L,removal ratio only is 59.29%.更多还原