Nguyen Tan Tai, Ma Hoa Thai, Avti Pramod, Bashir Mohammed J K, Ng Choon Aun, Wong Ling Yong, Jun Hieng Kiat, Ngo Quang Minh, Tran Ngoc Quyen
Department of Materials Science, School of Applied Chemistry, Tra Vinh University, Tra Vinh City 87000, Vietnam.
Department of Active Polymers and Nanomaterials Applications, School of Applied Chemistry, Tra Vinh University, Tra Vinh City 87000, Vietnam.
J Anal Methods Chem. 2019 Jun 2;2019:6210240. doi: 10.1155/2019/6210240. eCollection 2019.
In this work, SiO nanoparticles were prepared by the sol-gel method after sodium silicate was extracted from rice husk ash (RHA) under various experimental conditions such as types of acids, NaOH concentration, dissolved time, and temperature and used for removal of Fe ions from aqueous solutions. The extracted SiO was morphologically and chemically characterized and showed a surface area of 78 m/g and uniform pores of 2.71 nm, offering high adsorption capacity for Fe ions. The influence of pH, contact time, and amount of adsorbent was studied in order to establish the best conditions for the Fe adsorption and removal. Furthermore, the adsorption data were fitted with an exponential shape curve for all the three variable parameters that affect the adsorption process. The best results were obtained for pH 5, 20 min contact time, and 0.5 g adsorbent dose. The loading adsorption capacity was 9 mg of Fe ions/g SiO in the concentration range 0.1-1.0 mgL. In addition, the synthesized SiO with the size of around 50 nm can be used for specific heavy metal removal and drug delivery, after modification of the SiO surface with various functional groups.
在本研究中，通过溶胶 - 凝胶法制备了二氧化硅纳米颗粒，其中硅酸钠是在不同实验条件（如酸的类型、氢氧化钠浓度、溶解时间和温度）下从稻壳灰（RHA）中提取得到的，并用于从水溶液中去除铁离子。对提取的二氧化硅进行了形态和化学表征，其表面积为78 m²/g，孔径均匀为2.71 nm，对铁离子具有较高的吸附容量。研究了pH值、接触时间和吸附剂用量的影响，以确定铁吸附和去除的最佳条件。此外，针对影响吸附过程的所有三个可变参数，将吸附数据拟合为指数形状曲线。在pH值为5、接触时间为20分钟和吸附剂剂量为0.5 g时获得了最佳结果。在0.1 - 1.0 mg/L的浓度范围内，负载吸附容量为9 mg铁离子/g二氧化硅。此外，通过用各种官能团修饰二氧化硅表面，合成的尺寸约为50 nm的二氧化硅可用于特定重金属的去除和药物递送。
