作者簡介| 李曉東(1980—),男,副教授,吉林建築大學材料科學與工程學院,主要從事納米材料及環境化學方面的研究工作,研究方向為光催化材料、水分析化學等方面。
本文研究了納米介孔MCFs分子篩作為吸附劑,對Ni2+的優化吸附條件、吸附動力學性質、吸附等溫線、吸附熱力學性質。
Nano mesocellular foam silica (MCFs): An effective adsorbent for removing Ni2+ from aqueous solution
Xiao-dong Li a,*, Qing-zhou Zhai b
a Department of Basic Science, Jilin Jianzhu University, Changchun 130118, China
b Research Center for Nanotechnology, Changchun University of Science and Technology, Changchun 130022, China
* Corresponding author.
E-mail address: rcnrcn1@163.com (Xiao-dong Li).
Abstract
Nano mesocellular foam silica (MCFs) was synthesized through the hydrothermal method in this study. Powder X-ray diffraction and scanning electron microscopy were used to characterize the MCFs sample. The sample presented spherical particles and regular morphology. The results of transmission electron microscopy showed that synthesized MCFs has a three-dimensional honeycomb pore structure, which aids in the adsorption of nickel ion (Ni2+). The results of low-temperature nitrogen gas adsorption-desorption showed that the pore diameter of the synthesized MCFs was 19.6 nm. The impacts of pH, temperature, amount of adsorbent, initial concentration of Ni2+, and contact time on the adsorption effect of Ni2+ by MCFs were studied. Under the optimized adsorption conditions, the adsorption rate reached 96.10% and the adsorption capacity was 7.69 mg/g. It has been determined through the study of kinetics and adsorption isotherms that the adsorption of Ni2+ by MCFs follows the pattern of the pseudo-second-order kinetic model, simultaneously belonging to the Freundlich adsorption type. The thermodynamic results of adsorption showed that, when the temperature is between 25°C and 45°C, the adsorption is a spontaneous exothermic reaction.
Keywords
Wastewater treatment
納米介孔二氧化矽MCFs: 一種從水溶液中去除鎳(II)的有效吸附劑
李曉東, 翟慶洲
摘要:本研究採用水熱法成功製備出納米介孔泡沫二氧化矽(Mesocellular foams silica) 材料MCFs,並對其進行粉末X-射線衍射和掃描電子顯微鏡等表徵,樣品呈球形顆粒,形貌規則,其平均顆粒直徑為2.2 μm。透射電鏡結果表明,合成的MCFs具有3維蜂窩狀結構孔道,有利於重金屬離子Ni2+的吸附。低溫氮氣吸附-解吸附實驗結果表明,合成的MCFs具有19.62 nm的孔徑。本文研究了MCFs對重金屬離子Ni2+的吸附,研究了pH, 溫度, 吸附劑用量, 鎳(II)初始濃度, 接觸時間參量對吸附效果的影響。在優化吸附條件下,吸附率可達到96.10%,吸附容量為7.69 mg/g。通過研究動力學和吸附等溫線發現MCFs吸附Ni2+屬於準二階動力學模型,同時屬於Freundlich吸附類型。吸附熱力學結果表明,當溫度為25℃~45℃時,該吸附為自發進行的放熱反應。
關鍵詞:鎳; 吸附; MCFs; 動力學; 熱力學; 水熱法; 廢水處理
Fig. 1. Effect of pH on adsorption of Ni(II) (m = 0.050 g, C0 = 1.0 mg/mL, t = 40 min, and T = 25°C).
Fig. 2. Effect of adsorbent amount on adsorption of Ni(II) (pH = 2.0, C0 = 1.0 mg/mL, t = 40 min, and T = 25°C).
Fig. 3. Effect of adsorption temperature on adsorption of Ni(II) (pH = 2.0, C0 = 1.0 mg/mL, m = 0.050 g, and t = 40 min).
Fig. 4. Effect of initial concentration of Ni2+ on adsorption of Ni(II) (pH = 2.0, m = 0.050 g, t = 40 min, and T = 25°C).
Fig. 5. Effect of contact time on adsorption of Ni(II) (pH = 2.0, C0 = 1.0 mg/mL, m = 0.050 g, and T = 25°C).
Table 1. Comparison of adsorption capacity of Ni(II) from aqueous medium by various adsorbents.
Fig. 6. Pseudo-first-order and pseudo-second-order adsorption kinetic curves.
Table 2. Corresponding parameters of adsorption kinetic equations.
Fig. 7. Fitting curves of Langmuir and Freundlich adsorption isotherm equations.
Table 3. Langmuir isothermal equation data.
Table 4. Freundlich isothermal equation data.
Fig. 8. Adsorption thermodynamic curve.
Table 5. Adsorption thermodynamic data.
Fig. 9. XRD pattern of MCFs and MCFs-Ni(II) samples.
Fig.10. TEM and SEM images of MCFs sample.
Fig.11. Nitrogen gas adsorption-desorption pattern of MCFs sample.
Table 6. Parameter list of MCFs properties.
Fig.12. Fourier transform infrared spectrum of MCFs sample.
➤ Treatment of hydroxyquinone-containing wastewater using precipitation method with barium salt
https://doi.org/10.1016/j.wse.2019.03.003
➤ Biosorption of Ni(II) ions from aqueous solution using modified Aloe barbadensis Miller leaf powder
https://doi.org/10.1016/j.wse.2019.04.003
➤ Evaluation of copper removal efficiency using water treatment sludge
https://doi.org/10.1016/j.wse.2019.04.001
➤ Simulation of denitrification in groundwater from Chaohu Lake Catchment, China
https://doi.org/10.1016/j.wse.2018.07.004
➤ Effects of elevated atmospheric CO2 and nitrogen fertilization on nitrogen cycling in experimental riparianwetlands
https://doi.org/10.1016/j.wse.2017.05.005