Evaluation of Dyestuff Removal by Shea Nut (Vitellaria paradoxa) shells

The removal of textile dyestuff from waste water was investigated in a batch sorption process using shea nut (Vitellaria paradoxa) shell activated carbon. The data were tested using the Rudishkevich – Dubinin and Temkin isotherm models.  The result showed that removal efficiency increases with increase in contact  time. This critical study which utilizes these more recent adsorption isotherms  was found to present the mean free energy values (ED =1.036 – 1.406 kJmol-1) as a direct proportionality to the theoretical saturation capacities (qD = 2.032 – 4.169mgg-1). Sorption energy values proves to be higher for biosorbent, SS/A/15 (1.364 KJmol-1) ,which also gave the corresponding higher adsorption capacity (4.169 mgg-1) than the other three biosorbent in the series. A thermodynamic parameter (ΔG) was investigated to be more negative with sorbent – dye contact time, within the equilibration limit. The Close similarities of analytical results to those reported in reviewed literature, and the good degree of adsorption is an indication that using shea nut shells as a low cost biomass for generating activated carbon could be a feasible outlet in bioremediation. @JASEMJ. Appl. Sci. Environ. Manage. December, 2010, Vol. 14 (4) 163 - 16

Estimation of Specific Surface Area using Langmuir Isotherm Method

A comparison of four widely used linear equations of the Langmuir types of isotherm (The Langmuir Type 1, 2, 3 and 4 ) were examined in an experiment using dye sorption onto derived acid and salt treated Fish Activated Carbon (H3PO4-FAC and ZnCl2-FAC respectively). Isotherm parameters obtained from the four Langmuir linear equations differed. Though Langmuir type 1 is the most popular form, but the type 2 had the highest coefficient of determination (R2 = 0.931-0.984) compared with the other Langmuir linear equations (with R2 values ranges of 0.696-0.982, 0.613-0.926 and 0.613-0.926 for Langmuir type 1,3 and 4 isotherm models respectively). 3,7 bis(dimethylamino) phenothiazin-5-ium ion was used to measure the Extent of monolayer coverage (qm) and specific surface areas (SMB) following the application of type 1 isotherm. From this study, Value obtained for the Acid treated carbon (H3PO4-FAC with SMB; 18.170) is higher than that of the Salt treated carbon,  (ZnCl2-FAC, SMB ; 13.579) which compared more to that of commercial carbon, CAC (SMB; 13.884) units in multiple of 10-3km2kg-1. The reliability of the Langmuir type 1 and 2 methods seems very good in specific surface area estimation. @JASEMJ. Appl. Sci. Environ. Manage. December, 2010, Vol. 14 (4) 141 - 14