Abstract:

O/W/O double emulsion was prepared by using hydrophilic fumed silica N20 and hydrophobic fumed silica H30 to compounded surfactants, and polyacrylamide (PAM) porous microspheres were prepared by using this as a template, polymerizing the mesophase and volatilizing the inner phase, while their adsorption properties to methylene blue were tested. The results showed that the water oil ratio had a great influence on the formation of double emulsion, and when the water oil ratio (O₁/W)/O₂ was (1/2)/2, a stable double emulsion can be obtained. Scanning electron microscope (SEM) photos showed that PAM porous microspheres were basically spherical, but the particle size was uneven, the surface of the sphere was rough, and the interior was hollow. The results of Laser Particle Sizer (DLS) showed that the average particle size of PAM microspheres was 356nm, the polydispersity coefficient (PDI) was 0.718, BET surface area was 54.695m²/g, and the particle size distribution was wide. At the adsorption temperature of 35℃, the adsorption rate of methylene blue can reach 98.89% in 5s, which was better than the traditional PAM adsorbent in adsorption rate and adsorption quantity. This study provided a new method for the treatment of dye wastewater.

Key words: multiple Pickering emulsions, polyacrylamide, porous microspheres, adsorption

摘要：

采用亲水性气相二氧化硅N20和疏水性气相二氧化硅H30复配表面活性剂制备O/W/O型双重乳液，以此为模板，聚合中间相，挥发内相制备聚丙烯酰胺（PAM）多孔微球，并用于染料分子亚甲基蓝的吸附。结果表明：乳液显微镜照片显示水油比对双重乳液的形成有很大的影响，当水油比(O₁/W)/O₂为(1/2)/2时，可得到稳定的双重乳液；扫描电镜（SEM）照片显示PAM多孔微球基本呈球形，但粒径不均匀，球体表面粗糙，内部为空心结构；激光粒度仪（DLS）结果表明PAM微球平均粒径为356nm，多分散系数（PDI）为0.718，比表面积为230m²/g，粒径分布宽；在吸附温度35℃、吸附时间5min时对亚甲基蓝的吸附率为98.89%，最大吸附率超过99%，在吸附速率和吸附率上均优于传统PAM吸附剂，本研究为染料废水的处理提供了新方法。

关键词: 双重Pickering乳液, 聚丙烯酰胺, 多孔微球, 吸附