磷酸改性纳米黑碳的制备及对Cd的吸附研究

为提高纳米黑碳(BC)对Cd的吸附钝化效果,以磷酸为改性剂对BC进行改性,通过单因素实验探究不同改性条件对吸附性能的影响,分别改变磷酸浓度、反应温度、反应时间3个要因素,以Cd2+污染模拟水样为研究对象,确定最佳改性参数,同时使用Zeta电位仪、扫描电子显微镜(SEM)、X射线衍射(XRD)仪对磷酸改性纳米黑碳(MBC)进行表征,并且通过吸附等温线和吸附动力学实验研究MBC对于Cd^2+的吸附过程。研究结果表明,MBC改性最佳条件为2mol/L磷酸55℃水浴加热1.0h。吸附在20min后达到平衡,对Cd^2+的最大吸附量为345.329mmol/kg,为优惠吸附,等温吸附拟合更符合Langmuir方程。MBC表面孔隙度、比表面积、结晶度以及表面电荷数较改性前均明显增加,对Cd^2+有很强的吸附能力,适用于Cd污染治理。

Preparation of phosphoric acid modified nano black carbon and its adsorption of Cd

Nano-carbon black(BC)was modified with phosphoric acid.Through the single factor experiment respectively changing the phosphoric acid concentration,reaction temperature and reaction time,and simulated Cd2+ water sample as research object,the best parameters of the phosphoric acid modified nano-black carbon(MBC)production were determined.MBC was characterized by Zeta potentiometer,electronic scanning microscope(SEM)and X-ray diffraction(XRD).The adsorption process of MBC for Cd^2+ was obtained by adsorption isotherm and adsorption kinetic experiments.Research results showed that optimal parameters for the MBC was phosphoric acid concentration of 2 mol/L,55℃ water bath heating for 1.0 h.Adsorption reached equilibrium after 20 min.Maximum adsorption amount of Cd^2+ by MBC was 345.329 mmol/kg and a preferential adsorption,according with Langmuir equation.The characterization results indicated that the surface porosity,specific surface area,crystallinity and surface charge of the MBC were significantly increased.It was indicated that MBC had a strong passivation ability to Cd^2+ and suitable to repair Cd pollution.