Production of KMnO4 Modified Activated Carbon Fiber Filter from Pineapple Leaf Carbon Fiber for Fe3+ and Ca2+ Ions Adsorption

Objectives: The effects of ratios of KMnO₄ modified activated carbon fiber, zeolite, and sintering temperature for filter preparation were studies. The Fe³⁺ and Ca²⁺ ions removal by filter were also evaluated. Methods/Statistical analysis: The filters were characterized by XRD, FTIR, SEM-EDS, and BET analyzer. The percent drying shrinkage, percent firing shrinkage, percent total shrinkage, percent mass yield, density, and hardness were measured. The adsorption isotherms for Fe³⁺ and Ca²⁺ ions of the modified filter materials were also studied. Findings: The shrinkages and density properties increased with increasing sintering temperature and decreasing carbon fiber content, but hardness and mass yields showed a reverse trend. The filter has high content of MnO₂, Si and Al oxides, Pand O-contain functional groups, montmorillonite, and kaolinite. The BET, pore volume and pore size of the sintered filter materials are quite lower than those of the starting materials due to the effects of the functional groups on the filter surface. Application/Improvements: Langmuir isotherm and Freundlich isotherm were fitted for both Fe³⁺ and Ca²⁺ adsorption by the modified filter with theoretical maximum adsorption capacity of 45.25 and 23.53 mg/g, respectively.