The biosorption characteristics of SRCM 120569 biomass on anionic Congo red (CR) dye. SRCM 120569 strain isolated from Korean turbid rice wine (makgeolli) was identified by 16S rRNA sequence analysis as Bacillus licheniformis. Bacillus licheniformis SRCM 120569 (Genbank Accession No. MW819861) showed superior CR dye biosorption capacity in an aqueous solution. Maximum adsorption capacities of 61.2 and 133.1 mg/g were obtained at pH 3.41 and 0.01 g/50 mL dried cell dosage, respectively. The CR dye adsorption properties by the Bacillus licheniformis SRCM120569 strain were characterized by Fourier transform infrared spectroscopy (FT-IR), point of zero charge (pHpzc) analysis, and phylogenetic analysis. The biosorption isotherm and kinetic models are well described with the Langmuir adsorption isotherm and pseudo-second-order kinetic models.

In this research, Pb (II), Co (II), and Ni (II) toxic heavy metal ions adsorption from synthetic aqueous system have been studied using the activated carbon prepared from Citrus limetta leaves. Therefore, the relationship between the adsorption parameters (solution pH, dosage of adsorbent, temperature, initial concentration of the ions, and adsorption time) and the removal percentage of the prepared adsorbent have been investigated. Additionally, the adsorbent was analyzed through BET, SEM, EDX, FTIR, and XRD analyses. According to the results, the maximal adsorption efficiencies for heavy metal ions were achieved in pH = 6, the adsorbent dosage of 1 g/L, temperature = 25 °C, the ion initial concentration of 5 mg/L, and contact time of 60 min, which were 99.53%, 98.63%, and 97.54% for Pb, Co, and Ni ions, respectively. Based on Kinetic studies, the performance of pseudo-second-order kinetic model was better than pseudo-first-order model for the description of time-dependent behavior of the process. Additionally, the equilibrium data were fitted by Langmuir and Freundlich isotherms, while the former performed better than the latter. The maximum adsorption capacity values for Pb, Co, and Ni ions were achieved equal to 69.82, 60.60, 58.139 mg/g, respectively. Considering the thermodynamic data, the studied processes were exothermic and spontaneous.

One of the issues currently facing nuclear power plants is how to store spent nuclear waste materials which are contaminated with radionuclides such as 134Cs, 135Cs, and 137Cs. Bioremediation processes may offer a potent method of cleaning up radioactive cesium. However, there have only been limited reports on Cs+ tolerant bacteria. In this study, we report the isolation and identification of Cs+ tolerant bacteria in environmental soil and sediment. The resistant Cs+ isolates were screened from enrichment cultures in R2A medium supplemented with 100 mM CsCl for 72 h, followed by microbial community analysis based on sequencing analysis from 16S rRNA gene clone libraries (NCBI’s BlastN). The dominant Bacillus anthracis Roh-1 and B. cereus Roh-2 were successfully isolated from the cesium enrichment culture. Importantly, B. cereus Roh- 2 is resistant to 30% more Cs+ than is B. anthracis Roh-1 when treated with 50 mM CsCl. Growth experiments clearly demonstrated that the isolate had a higher tolerance to Cs+. In addition, we investigated the adsorption of 0.2 mg L-1 Cs+ using B. anthracis Roh-1. The maximum Cs+ biosorption capacity of B. anthracis Roh-1 was 2.01 mg g-1 at pH 10. Thus, we show that Cs+ tolerant bacterial isolates could be used for bioremediation of contaminated environments.

2013년 강우시 발생하는 월류수에 대한 수질배출기준이 추가됨에 따라, 효과적인 월류수의 처리공정 개발이 필요한 실정이다. 하수처리공정에서의 활성슬러지 군집(Floc)은 흡착제로써의 역할을 수행할 수 있는 물리화학적 구조를 띄고 있어, 월류수 중 오염물질을 흡착에 의해 제거할 수 있을 것으로 판단된다. 따라서, 본 연구에서는 활성슬러지의 생물흡착을 이용한 월류수 처리공정의 가능성을 평가하고자 하였다. 활성슬러지의 생물흡착성능을 평가하기 위하여, MBR공정에서의 활성슬러지를 활용하여 농도 및 흡착시간 등의 조건을 변경하여 효율평가를 진행하였다. 적정 조건에서 CODCr 및 CODMn 등의 유기물이 약 60% 이상 제거되었으며, 이를 통해 생물흡착에 의한 월류수 처리의 가능성을 확인하였다.

Batch sorption experiments were carried out for the removal of metylene blue from its aqueous solution using H3PO4 activated Acacia arabica carbon (AAC). The prepared activated carbon was characterized and was found as an effective adsorbent material. The operating variables studied were initial metylene blue concentration, AAC concentration and solution pH. AAC activated carbon posses a maximum sorption capacity for the range of initial dye concentrations studied (60~100 mg L-1). The sorption kinetics were analyzed using reversible first order kinetics, second order, reversible first order, pseudo-first order, and pseudo-second order model. The sorption data tend to fit very well in pseudo-second order model for the entire sorption time. The average pseudo-second order rate constant, KII and regression coefficient value were determined to be 0.0174 mg g-1 min-1 and 0.9977. The biosorption process also fit well to reversible I order kinetics with a regression coefficient of 0.9878.

The use of low cost and ecofriendly adsorbent has been investigated as an alternative to the current expensive method of removing dyes from wastewater. Cow dung cakes were collected from the nearby village which was burnt in a muffle furnace at 500℃ to obtain the required ash. This paper deals with the removal of Reactive Blue 221, Acidoll Yellow 2GNL and Olive BGL which are mainly used in textile industry, from aqueous solution by cow dung ash without any pretreatment. The adsorption was achieved under different pH, adsorbate concentration and the applicability of Langmuir and Freundlich isotherms were examined.

This study evaluated the biosorption properties of calcium ion using Aerobic Granular Sludge (AGS). A sequencing batch reactor was used to induce the production of Extracellular Polymeric Substances (EPS) through salinity injection, and the calcium ion adsorption efficiency was analyzed by a batch test. The EPS contents showed significant changes (104-136 mg/g MLVSS) at different salinity concentrations. The calcium ion adsorption efficiency was highest for AGS collected at 5.0% salinity, and it was confirmed that the biosorption efficiency of AGS was increased owing to the increase in EPS content. The results of the Freundlich isotherms showed that the ion binding strength (1/n) was 0.3941-0.7242 and the adsorption capacity (Kf) was 2.4082-3.3312. The specific surface area and the pore size of the AGS were 586.1 m2/g and 0.7547 nm, respectively, which were not significantly different from each other. It was confirmed that the influence of biological properties, such as EPS content, was relatively large among the factors affecting calcium ion adsorption.

This study was performed to find the effect of Enteromorpha prolifera as a biosorbent on the removal of heavy metals such as lead, copper, zinc and cadmium from the synthetic wastewater. The biosorption experiment was conducted using biomass of dried Enteromorpha prolifera, which has caused environmental pollution issues in oceans and lakes. To find the physico-chemical characteristics and adsorption capacity, parameters such as biosorbent dosage, initial heavy metal concentration, pH value of solution, contact time which influence the effects on heavy metals removal were changed and the optimum values were found through batch test. The experimental results showed that the sequence for adsorption capacity of heavy metals by Enteromorpha prolifera was Pb2+> Cu2+> Cd2+> Zn2+. The optimum conditions of pH, contact time and dosage of biosorbent were pH 5.0, 60 min. and 0.5 g/L, respectively. As initial heavy metal concentration increased, the adsorption capacity increased up to 17.53 mg/g for Pb with 98% removal efficiency. From the adsorption thermodynamic and kinetic analysis, the biosorption pattern of Pb, Cu, Zn and Cd was well described using Freundlich and Langmuir sorption isotherm with their R2 values of 0.99 and 0.97, respectively. The sorption kinetics followed pseudosecond order kinetic models and thus supported chemical sorption rather than internal diffusion. The work clearly indicates the potential of using Enteromorpha prolifera as an excellent adsorbent for heavy metal removal in industrial wastewater.

The biosorption of dye, Rhodamine B(Rh-B), onto waste activated sludge was investigated. The biosorption capacity and contact time were shown as a simulation of dye adsorption equilibrium and kinetics models. We observed that biosorption of Rh-B occurred rapidly less than 4hr. These experimental data could be better fitted by a pseudo-second-order rate equation than a pseudo-first-order rate equation. The equilibrium dependence between biosorption capacity and initial concentration of Rh-B was estimated and it was found that the equilibrium data of biosorption were fitted by four kinds of model such as Langmuir, Freundlich, Redlich- Peterson, and Koble-Corrigan model. The average percentage errors, ε(%), observed between experimental and predicted values by above each model were 21.19%, 9.97%, 10.10% and 11.76%, respectively, indicating that Freundlich and Redlich-Peterson model could be fitted more accrately than other models.

The properties of biosorption of dye(Rhodmine B) was investigated to figure out the effects of temperature as a function of dye concentration and sludge concentration by the Langmuir and Lagergen adsorption model. It was found that the uptake capacity of biosorption was increased at low temperature. The Langmuir adsorption model was found suitable for describing the biosorption of the dye. The experimental results indicated that the dye uptake process followed the pseudo-first-order kinetics.

Several effects on Pb2+ removal by crab shell from aqueous solution were investigated. As the increase of initial Pb2+ concentration and decrease of initial crab shell concentration, the time required to reach an equilibrium state and the residual Pb2+ concentration increased. In our experimental ranges, the optimum initial Pb2+ concentration and crab shell concentration were below 103 mg/l and over 0.5 mg/l, respectively. Also, in order to investigate the mechanism of Pb2+ removal by crab shell in aqueous solution, the crab shell was compared with chitosan and chitin on aspects of Pb2+ removal capacity and Pb2+ removal rate. The Pb2+ removal by crab shell was greater than that by chitin and chitosan. The role of chitin was not so great in Pb2+ removal by crab shell. The Pb2+ removal by chitosan was not exactly correlated to the molecular weight of chitosan.

Biosorption of Pb was evaluated for plants, Persicaria chinensis, Oenanthe javanica and Salvinia natans. The adsorption equilibrium was reached in about lhr for Pb and the highest adsorption capacity was 150㎎ Pb/g biomass at S. natans. Pb adsorption process showed a pseudo second order irreversible reaction. The highest initial adsorption rate was 2000㎎ Pb/g biomass/hr at O. javanica. In spite of pH variation, Pb adsorption capacity by P. chinensis was maintained uniformly. When light metals concentrations were increased in the solution, Pb was selectively adsorbed. The selectivity of mixture solution showed the adsorption order of Pb>Cu>Cr>Cd. The Pb adsorption capacity of P. chinensis pretreated with NaOH was increased by 30% in comparison with that of no treatment.

The biosorption abilities of different parts of waste brown seaweeds and their derivatives to remove heavy metals(Cd, Zn, Pb, Cu, Fe, Ni, Mn) from waste water were evaluated. The two parts of waste brown seaweeds (Undaria pinnatifida) were stems and sporophyls, and the brown seaweed derivatives were alginic fibers, active carbon added alginate(AC-alginate) and dealginate. The abilities of the sporophyls to adsorb the heavy metal ions were higher than those of stems, and those of alginates were slightly higher than those of dealginate in single ion solution. With decreasing the size of biosorbents, the velocity and the amount of adsorption increased. The abilities of alginate to remove the heavy metal ions increased in multi-ion solutions by adding active carbon to alginate. The selectivity of these biosorbents(alginate, AC-alginate) to lead ion was highest and to manganese ion was lowest.

In order to examine the availability and effectiveness of crab shell for the removal of heavy metals in aqueous solution, the crab shell was compared with cation exchange resin (CER), zeolite, granular activated carbon (GAC) and powdered activated carbon (PAC) on aspects of heavy metal removal capacity, rate and efficiency. In the removal of Pb, Cd and Cr, the heavy metal removal capacity of crab shell was higher than those of any other sorbents (CER, zeolite, GAC, PAC), and the order of heavy metal removal capacity was crab shell > CER > zeolite > PAC =～GAC. However, in the removal of Cu, the result of crab shell was slightly lower than that of CER. The initial heavy metal removal rate was affected by the sorts of sorbents and metals. In all heavy metals, the heavy metal removal rate of crab shell was higher than those of any other sorbents. Under the heavy metal concentration of 1.0 mmole/ℓ, the heavy metal removal efficiency of crab shell was maintained as 93∼100 %, which was much higher than those of any other sorbents.

The variation of microorganisms (activated sludge, Saccharomyces cerevisiae, Aureobasidium pullulans) caused by the biosorption of Pb2+ was observed by TEM and microscope. By the TEM observation of S. cerevisiae, the plasmolysis and lysis of cell wall or cell membrane were occurred by the penetration of Pb2+ into the inner cellular region. However, in the case of A pullulans, the plasmolysis and lysis of cell wall or cell membrane were not occurred because of the prevention of Pb2+ penetration by the extracelluar polymeric substances (EPS). A flocculation of microorganisms, in the case of A. pullulans, was observed by the Pb2+ accumulation after 3∼4 h and the color was changed from white to black after 1 day. The flocculation of activated sludge was improved by the accumulation Pb2+ after 1 h, however, the floc was broken up and the settling efficiency decreased after 1 day.

Pb2+ and Cr3+ uptake capacity by Sargassum horneri was 185.5㎎ Pb2+/g biomass and 102.6㎎ Cr3-/g biomass, respectively. An adsorption equilibria were reached within about 0.5 hr for Pb2+ and 1 hr for Cr3+. The adsorption parameters for Pb2+ and Cr3+, were determined according to Langmuir and Freundlich model. With an increase in pH values of 2 to 5, Pb2+ uptake was increased, however Cr3+ uptake was constant. The selectivity of mixture solution showed the uptake order of Pb2+>Cu2+>Cr3+>Cd2+. Pb2+ and Cr3+ adsorbed by S. horneri could be recovered from 0.1M HCl, 0.1M HNO3 and 0.1M EDTA by desorption process, and the efficiency of Pb2+ desorption was above 98%, whereas the efficiency of Cr3+ desorption was below 34%.

The biosorption and desorption of Cd were carried out using brown marine algae, known as the good biosorbent of heavy metals. The content of alginate bound to light metals could be changed by the physical and the chemical pretreatment of Sargassum fluitans biomass. The Cd uptake was independent of the alginate content. In case of protonated biomass, Cd uptake was the lowest because the alginic acid of biomass was dissolved to cadmium solution during the biosorption. The maximum Cd uptake of Sargassum biomass was ranged from 79㎎/g to 139㎎/g. In case of raw biomass, the higher the alginate content of biomass, the higher was the Cd uptake. 100% of Cd and light metals sorbed in the biomass were eluted at 0.1N HCl(pH 1.1). However, the elution efficiency in CaCl2 and Ca(NO3)2 solution was varied by the concentration, the solid to liquid ratio and the pH of calcium solution. The distribution coefficient between Cd and protons in the desorption solution at pH ranged from 1.6 to 2.9 was observed on the constant stoichometric coefficient(1.3).

Marine algaes are capable of binding a large quantity of heavy metals. We have investigated the uptake capacity of Pb and Cu by using 22 species of marine algae, collected from Korean coast. Among a variety of different marine algae types for biosorbent potential, Kjellmaniella crassifolia showed the highest uptake capacity of Pb. Metal uptake of Pb and Cu by Kjellmaniella crassifolia increase as the initial concentration rises, as long as binding sites are remained. The metal uptake parameters for Pb and Cu had been determined according to Langmuir and Freundlich model. By increasing pH. Pb uptake was increased and Cu uptake was constant. The maximum uptake capacity of Pb and Cu by Kjellmaniella crassifolia was 437 ㎎/g and 129 ㎎/g, respectively.

The biosorption of heavy metals has received a lot of attraction for application of metal ions treatment. In this work, we studied with Arthrobactor sp., screening from a wastewater containing heavy metals. The Pb uptake capacity of Arthrobactor sp. was nearly 146.9 ㎎ Pb/g dry biomass(initial concentration, 500 ㎎/L), whereas the Pb uptake capacity of Saccharomyces cerevisiae and Saccharomyces uvarum were only around 39.40 and 35.65 ㎎ Pb/g dry biomass, respectively. The Pb and Cr were removed from metal solution much more efficiently than were the other metals(Cd and Cu). The Pb uptake capacity of Arthrobactor sp. increased with increasing in pH(1.8, 3.0 and 4.0) and decreased with increasing of biomass concentration. At pH 4.0, the Pb uptake capacity reached 244 ㎎ Pb/ g dry biomass in Pb initial concentration of 1000 ㎎/L. The Pb uptake capacity of Arthrobactor sp. treated by KOH and CaCl_2 were increased above values obtained with untreated Arthrobactor sp. However, the Pb uptake capacity of Arthrobactor sp. treated by NaOH was decreased. The removal efficiency of Pb was kept above 99% before the breakthrough points were reached.