shells can be associated with a higher content of polysaccharide component, which
expands on the ability of the material to swell water.
Table 1 Characteristics of vegetal wastes of food industry
Material
Content of the main components, %
Volume of
adsorption
pores, cm
3
/g
Cellulose
Lignin
Ash
Resins, fats, waxes
Walnut shells
41,2
37,5
2,3
5,2
0,03
Apricot seed shells
34,6
48,1
2,5
5,0
0,03
Figure 2. Effect of the concentration of Fe
3+
on sorption capacity on vegetal
wastes: 1 – apricot seed shells; 2 – walnut shells
Isotherms and the linearized forms of the isotherm models for sorption of Fe
3+
on
studied materials are presented in Fig. 3.
a
b
c
Figure 3. Sorption isotherm for Fe
3+
(a), Langmuir isotherms for Fe
3+
(b)
Freundlich isotherms for Fe
3++
(c) on apricot seed shells (1) and walnut shells (2)
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