Potato Peels as an Adsorbent for Heavy Metals from Aqueous Solutions: Eco-Structuring of a Green Adsorbent Operating Plackett–Burman Design

Table 1

Comparison between the performance of PP prepared in the current approach and PP as reported in the literature. Adsorbent (PP) given name and abbreviations are as mentioned in the corresponding reference.

Adsorbent (PP)	Modification method	Analytical approach used	HM removed	BET surface area and pore volume	Adsorption capacity (mg/g)	Adsorption/removal (%)	Ref.
Potato residues	No chemical modification. Peels are washed and dried in an air oven at 80°C, 24 h, then grinded and sieved.	Univariate analysis	Cd (II); Cu (II); Ni (II); Zn (II); Mn (II); Fe (II)	ND	41–90 mg/g	ND	[21]
Untreated potato peel	No chemical modification. Peels washed, dried, and sieved, then dried in an air-circulating oven at 50°C for 7 days.	Univariate analysis	Cu (II)	ND	84.74 mg/g	ND	[22]
Activated carbon of potato peels; ACPP40; ACPP70; ACPP110; ACPP160	Peels were washed and dried for 24 h then impregnated by ratios of 40, 70, 110, and 160 wt.% of ZnCl2 and dried at 823°K for 4 h.	Univariate analysis	Cu (II)	ACPP40: 620 m^2/g, Vmicrop.0.18 cm^3/g; ACPP70: 810 m^2/g, Vmicrop.0.20 cm^3/g; ACPP110: 958 m^2/g, Vmicrop.0.24 cm^3/g; ACPP160: 1078 m^2/g, Vmicrop.0.26 cm^3/g	62–74 mg/g	ND	[23]
Po; PoP400; PoP600; PoP800	Potato peels were washed, dried for 24 h at 393°K and then impregnated with H3PO4 (75% w/w) for 24 h. Prepared samples were heated at different temperatures (400–800°C).	Univariate analysis	Co (II)	PoP400: 904.56 cm^2/g, and 0.726 cm^3/g; PoP600: 1041.43 cm^2/g, and 2.96 cm^3/g; PoP800: 0.91 cm^2/g, and 0.004 cm^3/g	373 mg/g; 405; mg/g; ND	87.5%; 92%; ND	[24]
Activated carbon of potato peels (ACP)	Chemical activation using H3PO4 in the presence of N2 at 600°C.	Univariate analysis	Pb (II)	498 m^2/g, and 2.960 cm^3/g	171 mg/g	ND	[25]
Potato peels charcoal (PPC)	Thermal activation. Peels are washed and dried in an air oven at 283°K, for 2 h, burned at 973 K for 2 h, then grinded and sieved.	Univariate analysis	Cu (II)	ND	0.3877 mg/g	99.8%	[26]
Current approach
RPP; BPP	See the Experimental section.	Multivariate analysis	Cd(II)	RPP: 4.075 m^2/g and 0.008 cm^3/g; BPP: 13.430 m^2/g and 0.017 cm^3/g	ND; 239.64; mg/g	64.09%; 99.19%