聚苯乙烯微球功能化及其定向控制造纸白水中DCS的研究

More attention was paid to the large amount of accumulated dissolved and colloidal substances (DCS) in the papermaking whitewater, due to its complicated components and negative effect on the papermachine runnability and paper quality. Thus how to oriented control the DCS efficiently has been the focused issue for many years. So a series of macroporous polystyrene (PS)spheres with high strength and high specific surface area will be firstly manufactured by suspension copolymerization. Then the oriented and efficient adsorption of DCS will be realized by respectively grafting the multilayer calcium ions, long chain β-cyclodextrin, poly (methyl acryloyl oxygen ethyl trimethyl ammonium chloride) and polyacrylic acid onto the PS sphere surface through atom transfer radical polymerization combined with multistage adsorption. The adsorption behavior of functionalized PS sphere for DCS components will be studied. The suitable eluant will be screened out and the elution curve will be built. The effect of PS sphere structure on the functionalization and adsorption of PS sphere will be investigated, and the influencing mechanism weill be revealed. The functionalized PS spheres will be utilized to adsorb the DCS models statically and dynamically, and the adsorption rules will be cleared. Thus the adsorption mechanism will be further revealed based on the adsorption isotherm and adsorption models. The research achievement will provide strong theoretical basis for improving the water recirculation and achieving energy conservation and emissions reduction.

造纸封闭循环白水中积累的大量溶解与胶体物质（DCS）因其组分复杂以及引起的纸机运行和纸页质量问题而备受关注，如何定向、高效对其进行控制成为人们多年来关注的热点。鉴于此，项目首先采用悬浮共聚合成系列高强度和高比表面积的大孔聚苯乙烯（PS）微球；之后通过原子转移自由基聚合在PS微球表面分别接枝多层钙离子、长链β-环糊精、聚甲基丙烯酰氧乙基三甲基氯化铵和聚丙烯酸，结合逐级吸附流程，实现对DCS中不同组分的定向、高效吸附。探究功能化PS微球对DCS不同组分的吸附行为，筛选洗脱液，建立洗脱曲线。研究PS微球结构对其功能化改性和吸附作用的影响行为和机制。利用功能化PS微球对DCS模型物进行静态和动态吸附，明确吸附规律，建立吸附等温线和吸附模型，进一步阐明吸附机理。研究成果为促进造纸系统用水封闭循环和实现节能减排奠定坚实理论基础。

随着我国造纸工业的迅速发展，纸机白水封闭循环回用被认为是实现造纸清洁生产、节能减排的重要途径之一。但是，随着纸机白水封闭循环程度增加，纸机系统中会积累大量有害的溶解与胶体物质（Dissolved and colloidal substances，简称DCS），给纸机运行和纸张质量带来严重不利影响。如何高效控制纸机白水中的DCS日益受到重视。本项目以大粒径聚苯乙烯树脂（Polystyrene，简称PS）白球为基体，采用原子转移自由基聚合或傅克反应或氧化还原自由基聚合，率先制备出表面分别负载阳离子基团、磺酸基团和金属离子、β-环糊精以及羧基和醛基的功能化PS树脂，解决了上述功能化基团难以在大粒径PS树脂表面进行高度聚合的难题，阳离子基团、磺酸基团和镁离子的固载量分别达到9.48 mmol/g、58 mmol/g和10.03 mmol/g，β-环糊精改性的PS树脂的增重率达到49.3%。并将负载阳离子基团的PS树脂用于DCS中阴离子杂质果胶的定向高效吸附和果胶酶的固定化，将负载金属离子和β-环糊精的功能化PS树脂分别成功应用于纸机白水DCS中糖类组分和树脂抽出物的定向高效吸附分离。优化了PS树脂功能化改性和功能化PS树脂对DCS的吸附工艺，明确了对造纸白水中DCS的吸附规律与效果。利用模型物的方法结合吸附模型，进一步阐明了吸附机理。阳离子化PS树脂对果胶的吸附为単分子层吸附，吸附动力学适合于颗粒内扩散；负载镁离子的PS树脂对木糖的吸附为单分子层吸附，吸附动力学适合于一级吸附动力学；β-环糊精改性的PS树脂对DCS的吸附为多分子层吸附，吸附动力学适合于一级吸附动力学。研究成果为PS树脂的功能化改性及造纸白水的高效处理奠定了坚实的理论基础和技术支撑，对于促进造纸工业清洁生产和节能减排具有重要理论意义和应用价值。