纳米Fe_2O_3与纳米SiO_2对石英砂表面改性的制备工艺优化研究  

Investigation on the optimum preparation process conditions of nano-iron oxide and nano-silicon oxide coated sand

作　　者：李冬梅[1] 庞治星[1] 赵向阳 李国浩[1] 刘贝[1] 秦梓源 李绍秀[1] 

机构地区：[1]广东工业大学土木与交通工程学院,广州510006 [2]佛山水业集团高明供水有限公司,佛山528500 [3]华南师范大学附属中学国际部,广州510630

出　　处：《环境科学学报》2013年第6期1598-1604,共7页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.51108094);广东省科技计划项目(No.2012B030900003)~~

摘　　要：以普通石英砂滤料为原材料,纳米Fe2O3、纳米SiO2为改性剂,环氧树脂为粘结剂,表面负载量和附着强度为评价指标,通过正交试验与固定因素不同水平连续性试验等方法,制备了两种纳米氧化物改性石英砂(Nano-oxide coated sand,Nano-OCS).同时,研究了不同制备因素对Nano-OCS表面氧化铁负载量和附着强度的影响,并探讨Nano-OCS制备工艺的最佳优化条件.结果表明,水浴加热过程对改性剂和粘结剂进行慢速搅拌,最佳转速为50r·min-1,时间为45min,烘干时间1h,温度(120±5)℃,纳米Fe2O3(65.8g·L-1)与未改性石英砂(RQS)的最佳投加比(体积质量比,下同)为C=0.23mL·g-1,改性剂环氧树脂(99%)溶液与RQS的最佳投加比为C1=0.035mL·g-1,纳米SiO2(10g·L-1)与RQS的最佳投加比为C2=0.17mL·g-1,在最优条件下制备的样品负载量和有机物吸附率均达到92%.投加过量时,有机物吸附率明显减小.与传统的低温碱性沉积法或高温煅烧制得的Nano-OCS相比,加入了粘结剂环氧树脂,用低温水浴固化的方法所制得的Nano-OCS,负载量提高了约8倍,脱附率降低70%以上.本法采用无添加剂的粘结剂,表面改性后不会对水体产生二次污染.The nano-iron oxide and nano-silicon oxide coated sand （Nano-OCS） are prepared with ordinary quartz sands as the raw material, nano-Fe2O3 and nano-SiO2 as the modifiers, and epoxy resin as the adhesive agent. By using the orthogonal test method, morphological properties analysis and semiquantitative analysis method by EDS, effects of different factors on surface loading and adherent strength of nano-OCS are analyzed. These factors include stirring frequency N, dosage ratio of nano-Fe2O3 , nano-SiO2 and epoxy resin, drying temperature T, time t, appearance of nano-OCS, etc. The optimum preparation conditions are obtained. In the process of water bath heating, modifiers and binders are mixed at a slow stirring speed, with the rotating speed of 50 r· min ^- 1 for 45 min, drying time of 1 hour with temperature at 120 ℃＋ 5 ℃. The optimal dosage ratios of nano-Fe2 03 （65.8 g· L^- 1 ） , the epoxy resin solution 99%, and nano-SiO2（10 g·L^-1） to raw quartz sand （RQS） is 0.23 mL·g^-1, 0.035 mL·g^-1 and 0.17 mL·g^-1, respectively. Both surface loading capacity and adsorption rate of Nano-OCS to organic mattress can be up to 92%. When the dosage is excessive, the adsorption rate is significantly reduced. As compared with Nano-OCS prepared by the alkaline deposition method at low temperature （T〈~ 110 ℃ ） and Nano-OCS which is prepared by calcining at high temperature （ T^300 ℃ ） , the loading capacity of Nano-OCS prepared by the addition of binder epoxy resin and the low- temperature water bath curing method increases by 8 times approximately, and the desorption rate decreases by more than 70%. The preparation method takes the binder without additives thus secondary pollution of Nano-OCS can be avoided.

关 键 词：纳米Fe2O3 纳米SIO2 环氧树脂 石英砂改性 表面负载量 附着强度 形态学 

分 类 号：X703[环境科学与工程—环境工程]