Eco-Friendly Synthesis of Copper Nanoparticles from Fiber of Trapa natans L. Shells and Their Impregnation Onto Polyamide-12 for Environmental Applications

Figures & data

Figure 1. FTIR spectra of PA-12/CuONPs before and after dyes’ adsorption.

Figure 2. BET adsorption – desorption isotherm.

Figure 3. HR-TEM of PA-12/CuONPs at different magnifications.

Figure 4. SEM images of PA-12/CuONPs (a-b), MO adsorbed PA-12/CuONPs (c), BG adsorbed PA-12/CuONPs (d).

Figure 5. Elemental mapping of PA-12/CuONPs (a), MO adsorbed PA-12/CuONPs (b), BG adsorbed PA-12/CuONPs (c).

Figure 6. EDS analysis of PA-12/CuONPs (a), MO adsorbed PA-12/CuONPs (b), BG adsorbed PA-12/CuONPs (c).

Figure 7. XRD pattern of PA-12/CuONPs (a), CuO nanoparticles (b) and PA-12 (c).

Figure 8. Thermogravimetric analysis (TGA) of PA-12/CuONPs.

Figure 9. Effect of pH on MO and BG adsorption onto PA-12/CuONPs.

Figure 10. Point of zero charge of PA-12/CuONPs.

Figure 11. Adsorption isotherm: Langmuir (a), Freundlich (b), Temkin (c) and D-R (d).

Table 1. Adsorption isotherm parameters of dyes’ adsorption onto PA-12/CuONPs.

Isotherm Model	Parameters	MO	BG
Langmuir	qm b R^2	166.6 0.0058 0.9989	55.24 0.136 0.9776
Freundlich	n Kf R^2	1.04 1.002 0.997	1.397 6.829 0.971
Temkin	B R^2	277.38 0.928	296.89 0.981
D-R	qm E R^2	20.46 1.255 0.953	15.78 0.317 0.870

Figure 12. Vant’s Hoff plot.

Table 2. Thermodynamic parameters of dyes’ adsorption onto PA-12/CuONPs.

Dye	Temp (K)	ΔG^0	ΔH^0	ΔS^0	R^2
MO	288	−0.9479338	18.98	0.069	0.9834
	298	−1.4978532
	308	−2.3352535
BG	288	−1.9080002	44.25	0.159	0.9363
	298	−2.8463477
	308	−5.1288202

Figure 13. Adsorption Kinetics: Pseudo-first-order (a), Pseudo-second-order (b), Elovich (c), Intraparticle diffusion (d).

Table 3. Kinetic parameters of dyes’ adsorption onto PA-12/CuONPs.

Kinetic Models	Parameters	MO	BG
Pseudo 1^st order	Qe(cal) Qe(exp) k1 R^2	10.799 16.8 0.011 0.8101	16.01 23.2 0.0168 0.9606
Pseudo 2^nd order	Qe(cal) Qe(exp) k2 R^2	18.01 16.8 0.0021 0.9714	25.5 23.2 0.0020 0.9958
Intraparticle Diffusion Model	Kid C R^2	1.238 1.981 0.8342	1.6309 5.022 0.9015
Elovich Model	A B R^2	3.505 −2.239 0.9485	4.482 −0.087 0.9878

Figure 14. Desorption efficiency of PA-12/CuONPs.