摘要
针对水中氟离子污染问题,提出利用生物模板辅助水热合成介孔氧化镁脱氟材料。以香蒲绒为生物模板,MgCl2为镁源,尿素为沉淀剂,通过水热-煅烧后,得到介孔氧化镁脱氟材料。对材料进行SEM、BET、XRD、FT-IR等表征,考察吸附剂用量、溶液pH值、共存阴离子等因素对脱氟效果的影响。结果表明,当氟离子浓度为50 mg/L时,在吸附剂用量为1.2 g/L、反应时间为90 min、pH=2~11、25℃条件下,脱氟效果均能达到98%以上,受共存离子Cl^(-)、SO_(4)^(2-)、NO_(3)^(-)、HCO_(3)^(-)、CO_(3)^(2-)影响不大,受PO_(4)^(3-)影响较大。吸附过程符合Langmuir吸附等温线和准二级动力学,饱和吸附量为109.82 mg/g,属于单分子层的放热过程。经5次循环吸附实验后,氟离子的去除率降至55.65%。
For pollution issues of the fluoride ions in water,the defluorinated material of mesoporous magnesium oxide with biotemplated-assisted is synthesized in this paper.Using cattail fiber(CFs)as a biological template,magnesium chloride as a magnesium source and urea as precipitating agents,the mesoporous magnesium oxide was synthesized by hydrothermal and calcination methods.The materials were characterized by SEM,BET,XRD and FT-IR.The effects of adsorbent dosage,solution pH and coexisting anions on the defluorination were investigated.The results showed that under the conditions of the fluoride concentration 50 mg/L,the amount of adsorbent 1.2 g/L,the reaction time 90 minutes,pH=2~11,and 25℃,the fluoride removal rate could reach over 98%.The fluoride removal process was not significantly affected by the co-existing ions such as Cl^(-),SO_(4)^(2-),NO_(3)^(-),HCO_(3)^(-),and CO_(3)^(2-),but greatly affected by PO_(4)^(3-).The fluoride adsorption process was well described by Langmuir adsorption isotherm model and pseudo-second-order dynamic model.The saturation adsorption capacity was 109.82 mg/g.The adsorption process was supposed to be dominated by monolayer exothermic.After 5 cycles of adsorption experiments,the removal rate of the fluoride ions was decreased to 55.65%.
作者
张家祺
李荻
李颖
杨海明
ZHANG Jiaqi;LI Di;LI Ying;YANG Haiming(School of Chemical Engineering,University of Science and Technology Liaoning,Anshan 114051,China;School of International Education,University of Science and Technology Liaoning,Anshan 114051,China)
出处
《辽宁科技大学学报》
CAS
2023年第1期26-32,共7页
Journal of University of Science and Technology Liaoning
基金
国家自然科学基金青年基金(51308276,51102126)
辽宁省教育厅优秀人才项目(二层次2015055)
辽宁省教育厅项目(2020LNJC06)
辽宁科技大学创新团队项目(2017TD02)
辽宁科技大学大学生创新创业训练计划(X202110146103)。
关键词
水热合成
生物模板法
香蒲绒
介孔氧化镁
hydrothermal synthesis
biological template method
cattails fiber
mesoporous magnesium oxide
