Sorption of cadmium(II) and zinc(II) ions from aqueous solutions by cassava waste biomass (Manihot sculenta Cranz)

248

116

Granular activated carbon produced from palm kernel shell was used as adsorbent to remove copper, nickel and lead ions from a synthesized industrial wastewater.Laboratory experimental investigation was carried out to identify the effect of pH and contact time on adsorption of lead, copper and nickel from the mixed metals solution.Equilibrium adsorption experiments at ambient room temperature were carried out and fitted to Langmuir and Freundlich models. Results showed that pH 5 was the most suitable, while the maximum adsorbent capacity was at a dosage of 1 g/L, recording a sorption capacity of 1.337 mg/g for lead, 1.581 mg/g for copper and 0.130 mg/g for nickel. The percentage metal removal approached equilibrium within 30 min for lead, 75 min for copper and nickel, with lead recording 100 %, copper 97 % and nickel 55 % removal, having a trend of Pb 2+ > Cu 2+ > Ni 2+ . Langmuir model had higher R 2 values of 0.977, 0.817 and 0.978 for copper, nickel and lead respectively, which fitted the equilibrium adsorption process more than Freundlich model for the three metals.

“…The uptake and percentage removal of metals from the aqueous solution are strongly affected by the pH of the solution (Horsfall and Abia, 2003;Zvinowanda et al 2009). Fig.…”

Section: Effect Of Ph On Adsorptionmentioning

confidence: 99%

Adsorption of copper, nickel and lead ions from synthetic semiconductor industrial wastewater by palm shell activated carbon

Onundi

Mamun

Khatib

et al. 2010

248

116

“…Chemically modified plant wastes were also used as adsorbents of heavy metals (Ngah and Hanafiah 2008). Among many biosorbents naturally available plant biomass (Manal 2007;Benhima et al 2008) can be used as an inexpensive method for metal ion removal from synthetic solution and industrial effluents (Horsfall and Abia 2003;Singh et al 2005;Zafar et al 2007). Adsorption processes using natural adsorbents or agricultural waste products are becoming the new alternative for waste water treatment as they are cheap, simple, sludge-free, and involve small initial cost (Matheickal and Yu 1997;Chandra et al 2003;El-Chaghaby 2007, 2008).…”

Section: Introductionmentioning

confidence: 99%

Adsorption of lead using a new green material obtained from Portulaca plant

Dubey

Shiwani

2011

In the present study the potential of a new green material obtained from Portulaca oleracea plant was investigated. The material was used without any chemical treatment to study the adsorption behavior of lead ions from aqueous solution. Various batch experiments were carried out using different experimental conditions such as pH, contact time, adsorbent concentration, and metal ion concentration to identify the optimum conditions. The influence of these parameters on the adsorption capacity was studied. Results showed the optimum initial pH for adsorption as 6. Adsorption equilibrium was reached in 120 min. The adsorption data were modeled using both the Langmuir and Freundlich classical adsorption isotherms. Results show *78% removal of lead from aqueous solution. The kinetic data corresponded well with pseudo second-order equation. From the initial results, the green material obtained from the waste of Portulaca seems to be a potential low-cost adsorbent for removal of lead ions from water.

“…Many investigators have used inexpensive sorbent materials such as cassava waste (Horsfall and Abia 2003), waste material (Ulmanu et al 2003), rice polish, and waste tea (Alhluwalia and Goyal 2005).…”

Section: Introductionmentioning

confidence: 99%

Application of dried plant biomass as novel low-cost adsorbent for removal of cadmium from aqueous solution

Dubey¹,

Mishra²,

Singhal³

2013

Heavy metals are a threat to human health and ecosystem. These days, great deal of attention is being given to green technologies for purification of water contaminated with heavy metal ions. Biosorption is one among such emerging technologies, which utilizes naturally occurring waste materials to sequester heavy metals from wastewater. Cadmium has hazardous impact on living beings; therefore, its removal through green and economical process is an important task. The aim of the present study was to utilize the locally available Portulaca oleracea plant biomass as an adsorbent for cadmium removal from aqueous solution. The biomass was obtained after drying and grinding the portulaca leaves and stem. No chemical treatment was done on the adsorbent so that it remained green in a true sense. Batch experiments were performed at room temperature. The critical parameters studied were effects of pH, contact time, initial metal ion concentration and adsorbent dose on the adsorption of cadmium. The maximum adsorption was found to be 72 %. The kinetic data were found to best fit the pseudo-secondorder equation. High adsorption rates were obtained in the initial 45 min, and adsorption equilibrium was then gradually achieved in about 100 min. Adsorption increased with increase in pH for a range 2 and 6. The equilibrium adsorption results closely followed both the Langmuir and Freundlich isotherms. The values of constants were calculated from isotherms. Results indicated that portulaca plant biomass could be developed as a potential material to be used in green water treatment devices for removal of metal ions.