Carbonaceous Hibiscus cannabinus L. for treatment of oil- and metal-contaminated water

The potential of carbonaceous Hibiscus cannabinus L. plant for use in the treatment of oil- and heavy metal-contaminated water is explored. The results from this work demonstrated that the material from this source was capable of sequestering oil and metal ions from the aqueous solutions. The maximum sorption to saturation capacities for diesel and cooking oil were 35 and 30 g g−1, respectively, well above that of the commercial adsorbent. The carbonaceous material was also effective for sequestering Mn2+, Cu2+ and Fe2+. The equilibrium of metal ions adsorption was attained after 30 min for Mn2+ and Cu2+, and 60 min for Fe2+ solutions. The sorption of the metal ions was in the order of Mn2+ > Cu2+ > Fe2+, increased with increase in the dosage in the range between 60% and 92% removal, depending on the dosage amount. The quantitative removal of Mn2+, Cu2+, and Fe2+ at pH 4.5, 50 mg L−1 initial concentration after 150 min equilibration time was 91.2%, 86.0% and 81.0%, respectively.