Adsorption of chromate by surfactant-modified zeolites and MCM-41 molecular sieve

Adsorption behaviour of functional grafting particles based on polyethyleneimine for chromate anions

“…However, the surface of these materials is usually charged negatively, so the adsorption and elimination effect for the chromate anions is poorer. Therefore, the researchers modify these clay minerals with cationic surfactants, and utilize the cationic characteristics of these surface-modified materials to enhance the removal efficiency for chromate anions [15][16][17][18][19].…”

Biosorption of Heavy Metals – New Perspectives

“…This improvement was met with success through different methodologies, which resulted in supports for the direct adsorption of chromate and dichromate ions or via indirect processes which first involve reduction of Cr VI . These methodologies can be separated into three categories: surfactant-modified zeolites [72][73][74][75][76][77][78], surface functionalization [79][80][81][82][83][84][85] and metal modification [86]. None of these processes requires changes promoted during synthesis or crystallization of zeolites, meaning they are applicable to natural zeolites as well.…”

Ferulic acid functionalized mesoporous silica polymer nanocomposites (SBA/FA) for the adsorption of Cr(VI)

“…are significant because of their ease of solubility in water and thereby making water more contaminated. Many methods with different adsorbents such as pH-sensitive hydrogels, polyhydroxybutyrate-bpolyethyleneglycol block copolymer, zeolites, clays, MCM-41, amino functionalized and magnetic mesoporous silica [20][21][22][23][24][25][26][27][28] have already been developed for the selective adsorption of Cr(VI) from various contaminated sources but still, no report is available for the selective adsorption of Cr(VI) on SBA/FA nanocomposites. Therefore, we report the structure-activity relationship of surface modified nanocomposites for the adsorption of the toxic metal ion Cr(VI).…”