These materials are regarded as good adsorbents because of their large specific surface area, high thermal and mechanical stability, homogeneous pore morphology, high functionalization, and high adsorption capacity .
To our knowledge, the removal of [Cd.sup.2+] by adsorption onto biomass ash, particularlyits modified product, has never been studied.
Morphology and FTIR studies have shown that its functional groups such as-OH, =C-H, C=O are responsible for adsorption of dyes (Bukhariet.al; 2013).
The sorbent was filtered through 50 mesh sieve, washed, dried at 60oC for 24 hrs and used for adsorption of DB-K2RL dye under optimum conditions following the procedure of (Jaikumar and Ramamurthi 2009).
Batch adsorption studies were carried out and the effect of experimental parameters Such as pH, initial dye concentration, temperature, adsorbent dose and contact time, on the adsorption of MB was studied.
The main conventional methods used to decontaminate waters are based on the membrane separation techniques [5-7], the reverse osmosis , the biological processing  and the adsorption .
Basar, "Applicability of the various adsorption models of three dyes adsorption onto activated carbon prepared waste apricot," Journal of Hazardous Materials, vol.
Palvannan, "Removal of plant poisoning dyes by adsorption on Tomato Plant Root and green carbon from aqueous solution and its recovery," Desalination, vol.
The literature also suggest a mechanism for which the adsorption of transitional metals on these kind of surfaces, through the formation of a covalent bond between the metal ion and the oxidic surface, called chemisorption, according to equation (2) where M could be any transitional metal.
Such kind of reaction modifies the surface charge through more positive values, which allows anion adsorption, and produces acidification through the formation of H3O+ ion.
Keywords: Adsorption, Pentaclethra macrophylla, Physisorption, Isotherm, Kinetics.
The decrease in the percentage adsorption could be accounted for by the fact that biosorbents have already fixed number of active sites which get saturated at higher concentrations leading to lower percentage removal of the metal ions by PMSAC .
The comparative experiments showed that the oxidization treatment is able to effectively improve the adsorption capacity of CNTs for [Cd.sup.2+] and produce many oxygen-containing groups, such as carboxyl and hydroxyl, on the surface of the original CNTs.
With the in-depth study on magnetic treatment, the combination of magnetic treatment and adsorption has become a new research focus.
is usually a primary process for the accumulation of heavy metals in soils while desorption is a main process for the removal.