Study of Adsorption Isotherms and Kinetics of Naphthalene from Aqueous Solutions by Multi -Wall Carbon Nanotubes

Most of the early aromatic hydrocarbon, naphthalene with two benzene rings causes anemia and damage to the retina. It is also toxic to plants and aquatic.The removal of this compound from water by multi-walled carbon nanotubes with the aim of determining the removal efficiency and optimum variables examination are reviewed.
Matherials & This study was done in Batch reactor to investigate the effects of Variations such as contact time ) 5¡15¡30¡60¡90¡120¡180 min), naphthalene concentration (0.1, 0.5,1,3,5,7.5,10,15mg/l and dose of nanotubes (0.01,0.05,0.1, 0.2,0.3,0.5,1,2)gr/l and pH(3,5,7,10in concentration3,7.5,10mg/l of naphthalene in removal of naphthalene. Experimental data were evaluated with Freundlich and Langmuir isotherm models for adsorption equilibrium and different isotherm models for kinetics of absorption were analyzed by comparing the total number coefficient of samples by the software.
Findings: Maximum surface adsorption of naphthalene onto multi-walledcarbon nanotubes was 33.3 mg/gr and maximum adsorption had occurred at acidic pH (pH =3), And appropriate time for receiving maximum adsorption of naphthalene and equalizationstate is 90 min. with increasing the adsorbent dose fro0.2 to 0.3 gr / l, removal efficiency of naphthalenesolution with 10 mg/l initial concentration increased from 97 %to 99.99 %, andwith increasing naphthaleneinitial concentration from 3 to 10 mg/l, removal efficiency increased from 73.33to 99.99 % at pH=3 after 90min. Adsorption mechanism consistent with freundlichIsoterm (R2=0.99)and followed pseudo first-order kinetics. (R2=0.96)
Discussion & Due to small size, large surface area and consequently very high reactivity of multi-walled carbon nanotubes, this adsorbent could be effective for removal of