Biosorption of copper ions from aqueous solution using Kappaphycus striatum

Abstract. Biosorption is an eco-friendly alternative technology for the removal of heavy metals from industrial waste and effluents using low-cost and effective biosorbent. Abundant of natural materials like agricultural biomass, industrial waste, and microbial biomass can be used as a promising biosorbent. In the present study, red algae Kappaphycus striatum biomass will be used for the adsorption of copper ions in aqueous solution. The free (non-immobilized) and immobilized form of red algae Kappaphycus striatum biomass and biosorption rate were investigated for the adsorption process. The maximum biosorption of copper ions was achieved when immobilized form of algae biomass were used at the condition pH of 5, biomass dosage, 0.25 g/L, contact time of 90 minutes, and at the temperature of 50 ℃ with a 65.8% of removal. The experiment data for biosorption rate with time also was used to evaluated two kinetic models (pseudo-first-order and pseudo-second-order) and two isotherm models (Langmuir and Freundlich). The results reveal that metallic ions biosorption on the immobilized Kappaphycus striatum followed the pseudo-second-order kinetic model with a R2=0.9996 and Langmuir isotherm model with a R2=0.9999. The present work shows that the red algae of Kappaphycus striatum as a potential biosorbent for the removal of heavy metal ions from aqueous solutio

Biosorption of CU(II) Ions by Leucaena Leucocephala Leave from Aqueous Solution

As a preliminary study, this project aims to remove the copper (Cu II) from aqueous solutions using Leucaena leucocephala leaves. Effect of free cell and immobilized form of biosorbent on adsorption capacity were evaluated in this study. Kinetic models of pseudo-first order, second order and equilibrium isotherms of Langmuir and Freundlich were used to predict the efficiency of Cu2+ absorption by Leucaena leucocephala leaves adsorption system. The functional groups involved during the adsorption were identified using Fourier Transform Infrared (FTIR) whereby the Leucaena leucocephala leaves has the large amount of hydroxyl functional groups at the wavelength of 3411.66 cm-1. Atomic Absorption Spectroscopy (AAS) were used to measure the metal concentration before and after the adsorption process. The maximum percentage removal of the Cu2+ was achieved by immobilized form of Leucaena leucocephala leaves as biosorbent in aqueous solutions with a 72.3% of removal. Adsorption kinetics of pseudo-second order was well fitted with the adsorption data with the R2 of 0.9622. In addition, the results reveal that Langmuir isotherm was the best model to explain the adsorption of Cu2+ using immobilized Leucaena leucocephala leaves with the R2 of 0.9974. This result showed that Leucaena leucocephala leaves as an effective and potential biosorbent for the adsorption of Cu2+ from the wastewate

Extraction of Tannic Acid from Kenaf Bast Fibre using Ultrasonic Assisted Extraction

Tannic acid or tannin, type of phenolic compound contains in kenaf bast fibre. Conventional extraction has certain limitations in terms of time, energy, and solvent consumption. Ultrasound assisted extraction (UAE) can extract bioactive components in shorter time, low temperature, with lesser energy and solvent requirement. UAE as alternative extraction technique is better equipped to retain the functionality of the bioactive compounds. In this study, the conditions for ultrasound assisted extraction (UAE) of tannic acid from kenaf bast fibre by assessing the effect of sonication time and different duty cycles were optimized. The use of ultrasound to extract tannic acid from kenaf bast fiber was evaluated. Ultrasound-assisted extraction (UAE) was carried out using ethanol as solvent to intensify the extraction efficacy. Phytochemical screening was conducted to identify the presence of tannic acid in extracts. The extracts then were analyzed using High-Performance Liquid Chromatography (HPLC) and Scanning Electron Microscopy (SEM). It was found that 0.2429 mg/mL of tannic acid was obtained under the extraction conditions of extraction temperature of 40℃, sonication time of 20 minutes and duty cycle of 50%. From SEM analysis, it was found that the raw sample demonstrated rough surface and no porous but kenaf bast fibre display smoother surface with less impurities and few pores appeared after the extraction process using UAE. These results indicate that ultrasound-assisted extraction is an efficient method for extracting tannic acid from kenaf bast fibre with the advantages of lower extraction time and higher extraction yield