Chemical Industry and Engineering Progress ›› 2025, Vol. 44 ›› Issue (11): 6716-6729.DOI: 10.16085/j.issn.1000-6613.2024-1684

• Resources and environmental engineering • Previous Articles    

Preparation and adsorption performance to methylene blue of fly ash based magnesium silicate nanosheets

LIU Qian(), LI Mengru, BAI Shouli, FENG Yongjun(), TANG Pinggui(), LI Dianqing   

  1. State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China
  • Received:2024-10-20 Revised:2024-12-18 Online:2025-12-08 Published:2025-11-25
  • Contact: FENG Yongjun, TANG Pinggui

粉煤灰基硅酸镁纳米片的制备及其亚甲基蓝吸附性能

刘倩(), 李梦茹, 白守礼, 冯拥军(), 唐平贵(), 李殿卿   

  1. 北京化工大学化工资源有效利用全国重点实验室,北京 100029
  • 通讯作者: 冯拥军,唐平贵
  • 作者简介:刘倩(2000—),女,硕士研究生,研究方向为无机功能材料。E-mail:2022201016@buct.edu.cn
  • 基金资助:
    国家重点研发计划(2022YFA1503400);国家重点研发计划(2023YFC3903700);国家自然科学基金(U1507119);国家自然科学基金(21627813)

Abstract:

The utilization of fly ash is of great significance to the sustainable development of society and environment. NaOH alkali fusion method was adopted to extract SiO2 from the silicon slag derived from fly ash after extraction of alumina. It was found that the SiO2 extraction rate reached 72.26% after reaction at 300℃ for 2h with the NaOH and ash mass ratio of 2∶1. Subsequently, MgSiO3 nanosheets were prepared by hydrothermal reaction using the obtained Na2SiO3 solution and MgO as raw materials. The effects of Na2SiO3 concentration, Si and Mg molar ratio, reaction temperature and time on the MgSiO3 product were investigated. XRD, SEM and low temperature N2 adsorption desorption instrument were used to analyze the composition and structure of the prepared MgSiO3, and its adsorption performance towards methylene blue (MB) was investigated. MgSiO3 with high purity, preferable crystallinity and a specific surface area of 240.6m2/g was prepared by reacting at 220℃ for 10h with Na2SiO3 concentration of 0.50mol/L and Si and Mg molar ratio of 1.25∶1. The as-prepared MgSiO3 nanosheets showed fast adsorption rate towards MB with an adsorption capacity of 285.0mg/g. Its adsorption behavior towards MB conformed to the quasi-second-order kinetic model and Langmuir isothermal adsorption model.

Key words: adsorbents, fly ash, silicon dioxide, magnesium silicate, hydrothermal synthesis

摘要:

粉煤灰的资源化利用对社会和环境的可持续发展具有重要意义。本文以粉煤灰基硅渣为原料,采用NaOH碱熔法提取SiO2,在碱熔温度为300℃、碱与灰质量比为2∶1、反应时间为2h的条件下,SiO2的提取率达到72.26%;进而以提硅得到的Na2SiO3溶液和MgO为原料,通过水热反应制备硅酸镁纳米片,考察了Na2SiO3溶液浓度、Si与Mg摩尔比、反应温度及反应时间对硅酸镁纳米片的组成、晶相结构和孔道结构的影响规律。结果表明,在Na2SiO3浓度为0.50mol/L、Si与Mg摩尔比为1.25∶1、反应温度为220℃和反应时间为10h的条件下制备了结晶度较好、比表面积达240.6m2/g的介孔硅酸镁纳米片;其对亚甲基蓝(MB)具有较快的吸附速率,吸附量达285.0mg/g,对MB的吸附行为符合准二级动力学模型和Langmuir等温吸附模型。

关键词: 吸附剂, 粉煤灰, 二氧化硅, 硅酸镁, 水热合成

CLC Number: 

京ICP备12046843号-2;京公网安备 11010102001994号
Copyright © Chemical Industry and Engineering Progress, All Rights Reserved.
E-mail: hgjz@cip.com.cn
Powered by Beijing Magtech Co. Ltd