Highly efficient scavenging of nitrophenol, arsenic (V), copper (II), dibenzothiphene, and carbazole by nanoporous silica/carbon adsorbents for remediation of oil and water pollutants

At present study, the removal of p-nitrophenol (PNP) by a newly designed mesoporous organocarbon, monolayers of ß-cyclodextrine (CD) on oxidzed ordered nanoporous carbon (OX-ONC) via ۱,۴-phenylene diisocyanate (PDI) linking denoted as CD-ONC was optimized. Furthermore, Au-doped mesoporous carbon CMK-۳ denoted as Au-OCMK-۳ was synthesized by using SBA-۱۵. Au-OCMK-۳ has been studied for removal of dibenzothiphene (DBT) and carbazole (CA) from n-hexane. Also the functionalization of SBA-۱۶ mesoporous with sulfonic acid for arsenic (As (V)) and copper (Cu (II)) removal were carried out (SBA-۱۶-SO۳H). Maximum absorption capacity of CD-ONC was ۱۰۰ mg/g. Dubinin–Radushkevich isotherm was applied to describe the nature of PNP uptake and it was found that it occurred physically (E = ۰.۰۷ KJ/mol, CD-ONC). Value for Temkin’s heat of adsorption is positive for PNP (۱۵۷.۸۷ J/mol, CD-ONC). There are two physisorption models of PNP with the surface C=O groups of ONC (H-bond and dispersion effect between phenolic ring and π electrons). The overall PNP adsorption process was exothermic and spontaneous in nature according to thermodynamics parameters (free energy (ΔGo), enthalpy (ΔHo), and entropy (ΔSo)). We demonstrate that functionalization of CMK-۳ with gold is possible (qm value for DBT: ۱۵.۳۳ mg/g and for CA: ۱۳.۰۰ mg/g). The adsorption capacity for As (V) on SBA-۱۶- SO۳H reaches ۹۲.۶۳ mg/g. The high removal of As equilibrium time of ۹۰ minutes can be explained in terms of a strong electrostatic attraction that occurred between the SO۳H and As. Maximum absorption capacity was ۹۲.۶۳ mg/g for As(V) was and ۱۳.۰۰ mg/g for Cu(II).

کلیدواژه ها:

Ligands-bridged mesoporous ، Taguchi method ، Response surface methodology ، Organic pollutants ، Inorganic pollutants