Adsorption of Heavy Metals in Contaminated Water Using Zeolite Derived from Agro-Wastes and Clays: A Review

Table 1

Summary of applications of common adsorbents [83].

Adsorbent	Pore diameter (nm)	Structure	Applications	References
Activated alumina	8.096		Removing HCl gas from hydrogen; Drying gases, transformer oils, and organic solvents; Removing fluorine in alkylation processes	[86, 87]
Silica gel	2–11		Dew point control for natural gas; Act as a desiccant; Drying gases, organic solvents, etc.	[81, 88]
Activated carbon	0.54–0.59		Removing odors; Purifying helium; Usage in water purification systems	[89, 90]
Zeolites	0.3–0.8		Separation of oxygen from air; Purifying hydrogen; Recovering carbon dioxide; Sweetening of sour gases and liquids	[81, 91]