Synthesis and adsorption application of amine shield-introduced-released porous chitosan hydrogel beads for removal of acid orange 7 from aqueous solutions

Abstract

12An effective and low-cost adsorbent named amine shield-introduced-released 13 porous chitosan hydrogel beads (APCB) was synthesized and characterized by SEM, 14 EDX, FTIR, XPS and Zeta potential. SEM images showed the porous structure of 15 APCB and EDX analysis proved the adsorption behavior of Acid Orange 7 (AO7) 16 onto APCB. FTIR analysis indicated that the amine-shield-release process and 1 amine-introduce process both increased the amount of amine groups. XPS analysis 2 confirmed the chemical compositions of the APCB. Zeta potential analysis indicated 3 that the pH pzc of APCB was 5.4. The significance of this work was illustrated by 4 excellent adsorption capacity towards AO7. The maximum adsorption was observed at 5 pH 2.0 with the adsorption capacity of 2803.77 mg g -1 . APCB showed low adsorption 6 capacity in high pH values and exhibited better AO7 adsorption capacity in low ionic 7 strength solutions. Experimental data were well fitted by pseudo-second-order kinetic 8 model and Langmuir isotherm model. Thermodynamic analysis indicated that the 9 adsorption process was spontaneous and endothermic. 10 Keywords: amine-shield chitosan; amine-introduce; acid orange 7 removal; 11 adsorption 12 aquatic diversity by reducing the penetration of light 2 . Therefore, several 17 technologies, like irradiation 3 , reverse osmosis 4 , ozonation 5 and adsorption 2 , have 18 been used to study the removal of hazardous dyes. Among these methods, adsorption 19 is one of the most effective methods for dye removal because of simplicity in design, 20

Surface modification of carbon black nanoparticles enhances photothermal separation and release of CO2

“…The new band appearing as a shoulder at 3180 cm -1 corresponds to N-H bond stretching [30]. The C-N stretching vibration is present at 1486 and 1034 cm -1 also appears in the CB-SO 2 -EDA spectrum [31]. The bands present in both the spectra of sulfonate and sulfonamide surface modified CB along with the TGA data suggests that desired functionality was introduced onto the surface covalently, and was further confirmed with the following described techniques.…”

Oxidation-Induced and Hydrothermal-Assisted Template-Free Synthesis of Mesoporous CeO2 for Adsorption of Acid Orange 7

“…Table 4 shows the maximum amount ( q m , mg/g) of AO7 molecule adsorbed per gram of various adsorbents from the recent literature [ 27 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 ]. By comparing the q m of various adsorbent, we could see clearly that the adsorption capacity of the mesoporous CeO 2 synthesized hydrothermally at 140 °C with 10 mL H 2 O 2 in this work was among the very highest in these reported works in the literature.…”