Thiourea-Isocyanate-Based Covalent Organic Frameworks with Tunable Surface Charge and Surface Area for Methylene Blue and Methyl Orange Removal from Aqueous Media
Yükleniyor...
Tarih
2022
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Mdpi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
A thiourea hexamethylene diisocyanate covalent organic framework (TH COF) was synthesized by adjusting the surface charge and surface area. The surface charge value of TH COF, -3.8 +/- 0.5 mV, can be changed to -29.1 +/- 0.4 mV by treatment with NaOH (dp-TH) and 17.1 +/- 1.0 mV by treatment with HCl (p-TH). Additionally, the surface area of TH COF was 39.3 m(2)/g, whereas the surface area of dp-TH COF and p-TH COF structures were measured as 41.4 m(2)/g and 42.5 m(2)/g, respectively. However, the COF structure had a better adsorption capability with acid and base treatments, e.g., dp-TH COF absorbed 5.5 +/- 0.3 mg/g methylene blue (MB) dye, and p-TH COF absorbed 25.9 +/- 1.4 mg/g methyl orange (MO) dye from 100 mL 25 ppm aqueous dye solutions, thereby increasing the MB and MO absorption amounts of the TH COF structure. Furthermore, by calculating the distribution, selectivity, and relative selectivity coefficients, the absorption capacity order was determined as dp-TH > TH > p-TH COFs for the MB dye, whereas it was p-TH > TH > dp-TH COFs for the MO dye. Finally, the reusability of dp-TH COF for MB absorption and p-TH COF for MO absorption were investigated. After five repeated uses, dp-TH COF retained 64.6 +/- 3.7% of its absorption ability, whereas p-TH COF preserved 79.7 +/- 3.2% of its absorption ability relative to the initial absorption amount.
Açıklama
Anahtar Kelimeler
porous coordination polymers, covalent organic framework, thiourea-isocyanate, absorbent, dye removal
Kaynak
Micromachines
WoS Q Değeri
Q2
Scopus Q Değeri
Q2
Cilt
13
Sayı
6
