PEI改性纸基材料的制备及其对水体主要污染物的去除

Preparation of PEI-modified Paper-based Material and Its Removal Performance on Major Pollutants in Water

中文关键词:  纸基材料  麦草浆  金属离子  染料  吸附  油水分离

Key Words:paper-based materials  wheat straw pulp  metal ions  dye  adsorption  oil-water separation

中文摘要:

      以麦草高得率浆为原料，戊二醛和聚乙烯亚胺为改性试剂，通过造纸工艺制得低成本、高湿强、具有优异吸附性能和油水分离性能的多功能纸基材料。改性纸基材料表面引入了大量氨基，含量可达3.33 mmol/g；其内部纤维间形成了共价键交联网络结构，湿抗张指数达到干抗张指数的29%。吸附实验研究表明，该纸基材料对吸附质的吸附动力学和热力学分别较好地拟合了准二级方程和Langmuir模型，其对刚果红和Pb²⁺的实际吸附容量分别为89.26和190.1 mg/g；理论最大吸附容量分别为91.04和232.4 mg/g。聚乙烯亚胺改性纸基材料对大豆油和正己烷的水下油接触角分别为152.5°和151.7°，具有水下超疏油性；此外，其对水包油乳液（平均粒径50 μm）的分离效率达到99.4%，膜通量达到12560 L/（m²·h）。

Abstract:

      A multi-functional paper-base material with low cost， high wet strength， excellent adsorption and oil-water separation performance was prepared by papermaking process using wheat straw high yield pulp as raw material， glutaraldehyde and polyethylene imine as modification reagents. A large amount of amino groups （3.33 mmol/g） were introduced onto the surface of the as-modified paper-based material and a covalent bond cross-linked network structure was formed between its internal fibers， resulting in a wet tensile index reaching 29% of the corresponding dry tensile index. The adsorption experimental show that the quasi-second-order equation and Langmuir model are well fitted to the adsorption kinetics and thermodynamics of the as-prepared paper-based material towards adsorbates （Congo red and Pb²⁺） with practical adsorption capacity of 89.26 and 190.1 mg/g， respectively， and the calculated maximum adsorption capacity of 91.04 and 232.4 mg/g， respectively. The under-oil contact angle of the modified paper-based material on soybean oil and n-hexane are 152.5° and 151.7°， respectively， indicating its super-hydrophobicity under water. Moreover， separation efficiency of the modified paper‍-‍based material on oil-in-water emulsion with average particle size of 50 μm reaches 99.4% and its film flux is up to 12560 L/（m²·h）.