Optimization, characterization, reversible thermodynamically favored adsorption, and mechanistic insights into low-cost mesoporous Fe-doped kapok fibers for efficient caffeine removal from water

This study explores the use of innovative Fe-Kapok fiber as an adsorbent to address persistent caffeine contamination in water. Kapok, a naturally abundant yet underutilized biomass, was modified with Fe particles to enhance its adsorption capacity. This study aimed to optimize the adsorption proces...

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Published inSeparation science and technology Vol. 60; no. 13; pp. 1643 - 1658
Main Authors Latiza, Rich Jhon Paul, Mustafa, Adam, Delos Reyes, Keno, Nebres, Kharl Laurence, Abrogena, Stephany Lera, Rubi, Rugi Vicente
Format Journal Article
LanguageEnglish
Published Taylor & Francis 02.09.2025
Subjects
Adsorption
caffeine
Fe-Kapok
natural adsorbent
optimization
regeneration
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Abstract This study explores the use of innovative Fe-Kapok fiber as an adsorbent to address persistent caffeine contamination in water. Kapok, a naturally abundant yet underutilized biomass, was modified with Fe particles to enhance its adsorption capacity. This study aimed to optimize the adsorption process by Box-Behnken Design, evaluate the performance of the material through isotherm, kinetic, and thermodynamic studies, and assess its regeneration potential and adsorption mechanism. The optimization revealed that the maximum caffeine removal (94.32%) was achieved under pH 5, a caffeine concentration of 50 mg/L, a contact time of 5 minutes, and an adsorbent dosage of 0.5 g/L. The adsorption process was best described by the Langmuir model (R 2  = 0.9993) with a monolayer capacity of 9.1429 mg/g at 40°C and followed pseudo-second-order kinetics (R 2  = 0.9999), indicating chemisorption. Thermodynamic analysis confirmed the process to be not spontaneous and endothermic, with positive entropy changes. Mechanistic insights suggest a multi-modal adsorption process involving key interactions such as electrostatic attraction, hydrogen bonding, π-π interactions, and coordination with Fe sites. Regeneration studies demonstrated durability of the Fe-Kapok, retaining 90.64% of its initial capacity after five cycles. The findings highlight efficiency and sustainability of Fe-Kapok as an adsorbent for caffeine removal.
AbstractList This study explores the use of innovative Fe-Kapok fiber as an adsorbent to address persistent caffeine contamination in water. Kapok, a naturally abundant yet underutilized biomass, was modified with Fe particles to enhance its adsorption capacity. This study aimed to optimize the adsorption process by Box-Behnken Design, evaluate the performance of the material through isotherm, kinetic, and thermodynamic studies, and assess its regeneration potential and adsorption mechanism. The optimization revealed that the maximum caffeine removal (94.32%) was achieved under pH 5, a caffeine concentration of 50 mg/L, a contact time of 5 minutes, and an adsorbent dosage of 0.5 g/L. The adsorption process was best described by the Langmuir model (R 2  = 0.9993) with a monolayer capacity of 9.1429 mg/g at 40°C and followed pseudo-second-order kinetics (R 2  = 0.9999), indicating chemisorption. Thermodynamic analysis confirmed the process to be not spontaneous and endothermic, with positive entropy changes. Mechanistic insights suggest a multi-modal adsorption process involving key interactions such as electrostatic attraction, hydrogen bonding, π-π interactions, and coordination with Fe sites. Regeneration studies demonstrated durability of the Fe-Kapok, retaining 90.64% of its initial capacity after five cycles. The findings highlight efficiency and sustainability of Fe-Kapok as an adsorbent for caffeine removal.
Author Mustafa, Adam
Nebres, Kharl Laurence
Abrogena, Stephany Lera
Latiza, Rich Jhon Paul
Delos Reyes, Keno
Rubi, Rugi Vicente
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Cites_doi 10.1016/j.chemosphere.2023.139667
10.1016/j.hazadv.2025.100591
10.1016/j.indcrop.2021.113261
10.1016/j.envres.2023.115822
10.1016/j.seppur.2022.120494
10.1021/acs.energyfuels.4c03095
10.1016/j.seppur.2024.126976
10.1515/eces-2019-0053
10.1016/j.carbpol.2018.02.018
10.1016/j.molliq.2020.112661
10.1016/j.envc.2021.100343
10.1007/s10853-025-10764-2
10.1016/j.enmm.2021.100594
10.1039/D2RA04501J
10.1016/j.cej.2018.03.132
10.1002/slct.202300928
10.1016/j.jece.2020.104795
10.1016/j.indcrop.2023.117960
10.1038/s41598-023-50937-0
10.1016/j.seppur.2023.124325
10.1016/j.seppur.2017.10.056
10.1016/j.matpr.2020.01.077
10.21577/0103-5053.20200231
10.1016/j.chemosphere.2024.141787
10.14416/j.asep.2024.07.005
10.1080/01496395.2025.2493281
10.3390/engproc2024067015
10.1016/j.chemosphere.2020.127336
10.1016/j.seppur.2018.07.037
10.1016/j.scitotenv.2017.11.117
10.1007/s11356-020-09053-z
10.1021/acsomega.2c08155
10.1016/j.hazadv.2025.100651
10.1016/j.jtice.2023.105205
10.1016/j.chemosphere.2020.125976
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References_xml – ident: e_1_3_4_28_1
  doi: 10.1016/j.chemosphere.2023.139667
– ident: e_1_3_4_2_1
  doi: 10.1016/j.hazadv.2025.100591
– ident: e_1_3_4_29_1
  doi: 10.1016/j.indcrop.2021.113261
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  doi: 10.1016/j.envres.2023.115822
– ident: e_1_3_4_8_1
  doi: 10.1016/j.seppur.2022.120494
– ident: e_1_3_4_19_1
  doi: 10.1021/acs.energyfuels.4c03095
– ident: e_1_3_4_11_1
  doi: 10.1016/j.seppur.2024.126976
– ident: e_1_3_4_17_1
  doi: 10.1515/eces-2019-0053
– ident: e_1_3_4_24_1
  doi: 10.1016/j.carbpol.2018.02.018
– ident: e_1_3_4_26_1
  doi: 10.1016/j.molliq.2020.112661
– ident: e_1_3_4_3_1
  doi: 10.1016/j.envc.2021.100343
– ident: e_1_3_4_34_1
  doi: 10.1007/s10853-025-10764-2
– ident: e_1_3_4_6_1
  doi: 10.1016/j.enmm.2021.100594
– ident: e_1_3_4_32_1
  doi: 10.1039/D2RA04501J
– ident: e_1_3_4_25_1
  doi: 10.1016/j.cej.2018.03.132
– ident: e_1_3_4_4_1
  doi: 10.1002/slct.202300928
– ident: e_1_3_4_15_1
  doi: 10.1016/j.jece.2020.104795
– ident: e_1_3_4_7_1
  doi: 10.1016/j.indcrop.2023.117960
– ident: e_1_3_4_10_1
  doi: 10.1038/s41598-023-50937-0
– ident: e_1_3_4_13_1
  doi: 10.1016/j.seppur.2023.124325
– ident: e_1_3_4_18_1
  doi: 10.1016/j.seppur.2017.10.056
– ident: e_1_3_4_31_1
  doi: 10.1016/j.matpr.2020.01.077
– ident: e_1_3_4_23_1
  doi: 10.21577/0103-5053.20200231
– ident: e_1_3_4_22_1
  doi: 10.1016/j.chemosphere.2024.141787
– ident: e_1_3_4_35_1
  doi: 10.14416/j.asep.2024.07.005
– ident: e_1_3_4_36_1
  doi: 10.1080/01496395.2025.2493281
– ident: e_1_3_4_5_1
  doi: 10.3390/engproc2024067015
– ident: e_1_3_4_21_1
  doi: 10.1016/j.chemosphere.2020.127336
– ident: e_1_3_4_12_1
  doi: 10.1016/j.seppur.2018.07.037
– ident: e_1_3_4_30_1
  doi: 10.1016/j.scitotenv.2017.11.117
– ident: e_1_3_4_27_1
  doi: 10.1007/s11356-020-09053-z
– ident: e_1_3_4_9_1
  doi: 10.1021/acsomega.2c08155
– ident: e_1_3_4_33_1
  doi: 10.1016/j.hazadv.2025.100651
– ident: e_1_3_4_16_1
  doi: 10.1016/j.jtice.2023.105205
– ident: e_1_3_4_20_1
  doi: 10.1016/j.chemosphere.2020.125976
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Snippet This study explores the use of innovative Fe-Kapok fiber as an adsorbent to address persistent caffeine contamination in water. Kapok, a naturally abundant yet...
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SubjectTerms Adsorption
caffeine
Fe-Kapok
natural adsorbent
optimization
regeneration
Title Optimization, characterization, reversible thermodynamically favored adsorption, and mechanistic insights into low-cost mesoporous Fe-doped kapok fibers for efficient caffeine removal from water
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