Analysis of the Adsorption Behaviour of Cadmium on Aluminium-Pillared Diatomite in a Solid/Liquid System Using Classical Adsorption Theory

Abstract

A readily available effective adsorbent is necessary to adsorb heavy-metal ions from aqueous solutions. In this study, a novel adsorbent with good adsorption properties [Al 3+ -oligomer-pillared diatomite (Al 3+ -oligomer-PD)] was prepared and was used to adsorb Cd 2+ ions in a solid/liquid system. The property and nature of the Cd 2+ ions adsorbed on the surface of the Al 3+ -oligomer-PD were studied by performing a series of adsorption tests and related surface property analyses. Our study results show that owing to a more favourable pore structure, the PD has a higher adsorption property compared with natural diatomite (ND) and most other common adsorbents. The adsorption capacity of PD is 27.36% greater than ND and also achieves an optimal value of 10.05 mg/l. Certain parameters have a significant effect on Cd 2+ ion adsorption. The most suitable isotherm and kinetics models for describing the adsorption of Cd 2+ ions are the Freundlich and pseudo-secondorder models. The nature of Cd 2+ ion adsorption on PD is favourable, physical, spontaneous, exothermic and disorder increasing. The results of the study suggest that PD is an ideal adsorbent for the removal of cadmium ions from aqueous solutions.

Composite of biomass and lead resistent Aspergillus oryzae for highly efficient aqueous phase Pb(II) adsorption

“…As shown in Table 1, the values of R 2 proved that the Langmuir and Freundlich model fitted the experimental data well, whereas the D-R model was not able to capture the experimental data at all, but the R 2 of D-R model have distinct advance after biosorbent combined with HA. In generally, the difference of correlations between experimental data and adsorption isotherm model can be used in the analysis of adsorption mechanisms [28][29][30][31]. Langmuir model was often used to describe monolayer chemical adsorption occurring on homogeneous surface.…”

Study on a Real-Time Control Strategy to Cr(VI) Removal with Fluctuation of Influent in Fe-Electrocoagulation-Al-Electroflotation Reactor

“…6 Other studies deal it with the indirect indicators (surrogate parameters) control strategy, such as differential UV absorbance, dissolved organic carbon and biological dissolved organic carbon, etc. 7,10,12,13 The indirect indicators are easily and cheaply detected by sensors and correlates well with the pollutant in the treatment system, thus provide an acceptable balance between quality and costs. 5 The major algorithm models of real-time control strategy generally fall into two categories: mechanism models and empirical models.…”