高疏水纤维生物炭处理含油废水特性与机制  

Profiles and mechanism of highly hydrophobic fiber biochar for oily wastewater treatment

作　　者：陈金辉 CHEN Jinhui(China Railway Siyuan Survey and Design Group Co.,LTD.,Wuhan 430063,China)

机构地区：[1]中铁第四勘察设计院集团有限公司武汉430063

出　　处：《环境工程学报》2025年第3期636-645,共10页Chinese Journal of Environmental Engineering

摘　　要：以模拟含油废水为对象,本研究制备了高疏水纤维生物炭,并探究了该材料的主要除油工艺参数以及除油机制。结果表明,在相同条件下,纤维生物炭的除油率达94.3%,显著优于其他材料;当投加量为0.3 g·L^(−1)、反应pH为2.4~11.6、温度11~25℃、初始油浓度为50~2000 mg·L^(−1)时,纤维生物炭对油类污染物的去除率达87.5%~95.3%。表征结果显示,纤维生物炭表面具有典型的沟槽和转曲特征,以及无定型炭结构,其C−C和C−O基团比例高于原始棉基材料。此外,纤维生物炭与水的平均接触角达145.2°,其表面自由能(71.36 mN·m^(−1))低于原始材料(77.8 mN·m^(−1)),说明该材料具有较强的疏水亲油性,有利于其吸附除油过程。纤维生物炭除油机制主要包括3个步骤:1)当分散的油滴接近纤维生物炭或接近已附着在纤维生物炭表面的油滴时,通过多种物理作用以及化学作用实现对油滴的高效吸附去除;2)然后黏附在纤维表面或聚集于已附着在纤维表面的液滴,经过拦截、惯性碰撞、捕获、融聚、聚结等作用而持续长大;3)纤维生物炭表面的油滴继续进行迁移聚结以及纤维表面更新等异化过程。In this study,a novel fiber biochar with high hydrophobicity was prepared and applied to treat synthetic oily wastewater,and the effects of main parameters on the oil removal efficiency by fiber biochar were investigated.The results showed that under the same conditions,the efficiency of oil removal by fiber biochar reached 94.3%,which was significantly better than that of other four materials.When the dosage of fiber biochar was 0.3 g·L^(−1),the pH was 2.4~11.6,the temperature was 11~25℃,and the initial oil concentrations were 50~2000 mg·L^(−1),the removal efficiencies of oily pollutants were 87.5%~95.3%.Moreover,the contact angle between fiber biochar and water was 145.2°,and the surface free energy of fiber biochar(71.36 mN·m^(−1))was lower than that of original cotton-based material(77.8 mN·m^(−1)),which indicated that the fiber biochar had strong hydrophobicity.Hence,a three-stage sorption mechanism of oil removal by fiber biochar was speculated:1)When fine drops of oil were close to the fiber biochar or close to oil droplets that had already been attached on the surface of the material,a large number of oil droplets could be adsorbed through physical and chemical process;2)These slightly larger oil droplets were continued to grow through interception,inertial collision,capture,fusion,and coalescence;3)The oil droplets on the surface were continued to migrate and agglomerate and the surface of fiber biochar was renewed in the process of alienation.

关 键 词：含油废水 纤维生物炭 除油效率 疏水性能 除油机制 

分 类 号：X703[环境科学与工程—环境工程]