In this study, biosorption potential of nine epiphytic bacteria isolated from the rhizosphere of Lepironia articulata and Scirpus grossus were assessed. Identification of the isolated epiphytic rhizobacteria using 16S rRNA analysis showed species belonging to the four genera of Bacillus, Enterobacter, Aeromonas, and Chromobacterium. Batch biosorption studies were carried out to assess the capacity of the isolated bacteria to act as Pb and Cu biosorbents. Different initial concentrations of the two heavy metals (50, 100, 200, 300, and 400 ppm) were used to determine the ability of the biosorbent to reach a tolerance level and then calculate the percentage of biosorption with respect to 0.1 g dry weight. Initial concentration of Pb and Cu exposed showed that the isolated bacteria have high tolerance up to 400 ppm. Bacteria prefer Pb ions over Cu, which is indicated by higher removal of Pb in all tested reactors. Bacillus sp. (coded Sc1) showed the highest biosorption capacity with 100% Pb and 97% Cu removal.
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Przedstawiono symulację biosorpcji jonów miedzi na granulkach alginianowych dla ustalonych wartości temperatury procesu. Ze względu na koszty związane z etapem chłodzenia często wymagane jest prowadzenie procesów w temperaturze zbliżonej do temperatury otoczenia. Na podstawie zaproponowanego modelu matematycznego obliczono skuteczność procesu biosorpcji w wąskim zakresie temp. 20-25°C, często stosowanym w przemyśle. Uzyskane wyniki dowodzą dużej wrażliwości procesu biosorpcji na zmianę temperatury. Obliczone wartości efektywnego współczynnika dyfuzji Deᵀ mieszczą się w przedziale 0,55-0,67∙10⁻⁹ m²/s, a przedstawione wyniki potwierdzają możliwość łatwego prognozowania De za pomocą proponowanej metody.
EN
A math. model of the biosorption process of Cu ions by alginates was created. The biosorption efficiency was detd. using the values of the effective diffusion coeff. (De) depending on the temperature, pH of the Cu soln. (P) and alginate content in the granules (C). Formulas for calcg. P and C were developed for the biosorption process carried out at temp. in the range of 9.8-60.2°C. The results prove the sensitivity of the biosorption process to temp. changes. The calcns. enable easy prediction of the effective diffusion coeff. De of the biosorption process.
This study investigated the efficiency of copper and manganese adsorption by bacterial cellulose (BC) produced from Komagataeibacter intermedius BE073. BC was collected from production processes in a village in Nakhon Nayok province. BC had high moisture content of 91.15±3.68%, an average water absorption index (WAI) of 5.30±0.362, an average tensile strength of 99.1 ±6.18 MPa, average elongation at break of 6.41±0.67%, and an average Young modulus of 1445±177 MPa. Structural analysis of the BC material shows that it is a cellulose powder with a main group. Measurements show that the Mn content in BC rapidly decreased after soaking in solution, and that the highest Cu absorption efficiency of BC during a 120 minute period was 15469 mg kg-1. The results of this study show that BC may be successfully used to absorb various heavy metal residues from leachate, particularly Cu solutions. BC cannot absorb Mn from solution, so it cannot be used to absorb Mn from leachate. However, studies have shown that BC can release Mn into solution. Therefore, BC may be effective for use in agriculture, as Mn is a micronutrient for plants.
Aloe vera leaves (AVL), a by-product of agricultural waste, have been applied as a biosorbent for reducing Ni(II) ions in aqueous solutions. The biosorption capability of AVL powder was enhanced through chemical treatment with 0.10 M citric acid solution. Fourier-transform infrared (FTIR) spectrophotometer, scanning electron microscope coupled with energy dispersive X-ray (SEM-EDX), pH of point-zero-charge (pHPZC), and pHslurry analyses were used to study the surface, and chemical properties of citric acid-treated Aloe vera leaf powder (CAAVLP). The setting for experiments such as pH solution, CAAVLP dose, initial concentration, and biosorption time was investigated. Maximum Ni(II) ion biosorption capability was determined to be 48.65 mg/g based on the Langmuir model at pH 6, a CAAVLP dose of 0.02 g, initial Ni(II) concentrations of 5 to 50 mg/L and biosorption time of 120 min. The data for the isotherm and kinetics were well matched with the Freundlich and pseudo-second-order models, respectively, with high regression correlation (R2) and low chi-square (χ2) values. The presence of more-COOH groups after treating AVL with citric acid resulted in more Ni(II) ions being able to be removed.
Autochthonous fungi are potential successful agents in the process of bioremediation through their efficient adaptation to pollutant toxicity and competition with other microorganisms that are present in the leachate treatment plant. The leachate from municipal waste landfills was an important source of fungi. Even though some of these fungi have the potential to be human pathogens, such strains wh en used in biolo gical treatment approaches may serve as a possible tool for integrating the leachate bioremediation process because of the extracellular enzymes produced by fungal strains. In this study, the leachate sample was tested with regard to four parameters, including total dissolved solids (TDS), electrical conductivity (EC), pH, and the decolorization of the leachate sample by a number of indigenous species of fungi, which were observed by use of the culture techniques. The scanning electron microscope coupled with energy dispersive x-ray analysis, UV-spectrum, and reflected and transmitted polarizing light microscope were used in the research project to o bserve and assess the obtained data from the experimental work. The results indicated the various levels of efficiency of the isolated fungal strains in eliminating color, lowering TDS, EC, and pH through their geoactivities potential in metal biosorption and immobilization by biomineralization of new minerals in the growth environment and eventually reducing the metal bioavailability and toxicity.
The removal of cadmium (II) and lead (II) ions from aqueous solutions by the Ziziphus lotus fruits powder, as inexpensive and eco-friendly biosorbent, was studied in batch mode. Fruits powder (FP) revealed the highest uptake rate at pH=8 and pH=7 for Cd(II) and Pb(II) consecutively. The best metal adsorption rate is obtained with a temperature ranging from 25 to 30 °C, a contact time of 90 min, an initial ionic concentration of 100 mg/L, and a biosorbent dosage ranging from 3.5 to 5 g/L.The experimental kinetic data of the biosorption process for both heavy metal ions were fitted by the pseudo second order model. The equilibrium data fitted very well to the Langmuir model. The maximum monolayer biosorption capacities were 33.94 mg/g and 69.06 mg/g for Cd(II) and Pb(II) respectively. The main chemical groups which are involved in the trapping of Cd(II) and Pb(II) and which have been revealed by FTIR spectral analysis are: N–C, O=C, H-O, H-C, and O–C. The present research confirms that Z. lotus fruits could be exploited as a low-cost and an effective biosorbent for the elimination of Cd(II) and Pb(II) ions from aqueous solution.
The objective of this research was to evaluate the adsorption capacity of the shell biomass (Dioscorea rotundata), taking into account the impact of temperature, bed height, and particle size on the removal of nickel(II) ions in aqueous solution in a continuous fixed-bed column system; performing the modelling of the break curve. The biomass was characterised by SEM-EDS analysis. The analysis found that it represents a rough, heterogeneous structure, rich in carbon and oxygen, with mesopores, and is suitable for removing heavy metals. It also determined the optimum parameters of the bed height, particle size, and temperature, keeping the pH and the initial concentration of the solution constant. The results revealed that the bed height and the particle size are the two most influential variables in the process. Ni(II) removal efficiencies range between 85.8 and 98.43%. It was found that the optimal conditions to maximise the efficiency of the process are temperature of 70°C, 1.22 mm particle size, and 124 mm bed height. The break curve was evaluated by fitting the experimental data to the Thomas, Adams-Bohart, Dose-Response, and Yoon-Nelson models, with the Dose-Response model showing the best affinity with a coefficient of determination R2 of 0.9996. The results obtained in this research showed that yam shell could be suggested as an alternative for use in the removal of Ni(II) ions present in an aqueous solution in a continuous system.
This research was conducted to overcome the Cu2+ heavy metal pollution in the environment through a biotechnological approach with heavy metal sorption process by microalgae beads. Biosorbent in form of beads was produced from Chlorella sorokiniana, Monoraphidium sp., and Scenedesmus obliquus tropical microalgae mobilized with Naalginate polymer. The sorption process is observed on a controlled batch culture with variations of temperature (25, 35, and 45 °C), and observation periods (200th, 220th, 250th, 270th min) as contact time. The absorption efficiency on each temperature variation reaches more than 90%, but the highest absorption efficiency rate is at 92.20% on 35 °C temperature and 200 minutes of contact time. Biosorbent beads with 2–3 mm of diameters show the best sorption ability than the 3–4 mm and 4–5 mm ones. Sorption process is also evident with the existence of intensity alteration on amide, ketone, and sulfhydryl function groups which were consistently weakened until the end of the sorption process. The beads utilized in this research are potentially reusable as biosorbent. Thus, further examination is required to acknowledge the maximum reutilization rate of the beads as biosorbent on heavy metal absorption process.
In this paper, the biosorption capacity of activated sludge sand bed was investigated for copper removal from wastewater. A sand bed consisting of three layers was used for the study: (1) filter gravel with a diameter of 2 to 3 mm, (2) a biological part inoculated with 200 ml of flocculent activated sludge with a dry weight of 5 kg/m3, (3) filter sand with a grain diameter of about 3 mm. The filter was fed with model wastewater prepared with sodium acetate, potassium nitrate, ammonium chloride, and potassium dihydrogen phosphate I and II basic. The source of Cu ions in the wastewater was CuSO4. The model wastewater used in this study was collected every 24 hours. The experiment was terminated when the concentration of Cu in the treated wastewater sample was equal to that in the treated wastewater. Such a phenomenon was indicative of the depletion of the sorption capacity of the tested bed, which was observed after 26 days. The concentration of copper in raw and effluent from the bed was studied using atomic absorption spectroscopy (ASA) in samples mineralized in nitric acid (HNO3) with the addition of perhydrol (H2O2). Two equilibrium models, Langmuir and Freudlich, were analyzed to study the absorption isotherms.
Technologia procesu uzdatniania wody dzieli się na dwa stopnie. Pierwszy, bardzo dobrze rozpoznany, oparty na procesie napowietrzania, koagulacji i filtracji przez złoża kwarcowe lub antracytowo-kwarcowe, drugi oparty na filtracji przez granulowany węgiel aktywny, najczęściej połączony z procesem ozonowania. Wielu jednak producentów wody nie decyduje się na proces ozonowania z uwagi na koszty inwestycyjne oraz koszty eksploatacyjne wpływające na cenę wyprodukowania 1 m3 wody.
The study presents the possibility of using chlorophyta in the removal of cadmium and lead ions from industrial wastewater produced after the washing of equipment used in the manufacture of battery and batteries. The process was conducted with the use of two algal cultures: Raphidocelis subcapitata produced in laboratory conditions, and a mixed chlorophyta population collected from a natural, eutrophicated water reservoir with heavy metal ions present in the water and sludge. The study showed that the effectiveness of a pure algal culture is comparable to that of a mixed chlorophyta population, characterized by greater diversity of functional groups at binding sites and higher resistance to stress that may occur in the wastewater environment. The maximum effectiveness of ions sorption was 64% for cadmium (mixed algal population) and 60% for lead (Raphidocelis subcapitata).
The sorption of 241Am3+, 85Sr2+ and 137Cs+ by calcium, strontium and barium alginates has been studied under different operation conditions. The most prominent adsorption was found in the pH range of 5–6 for all systems, even if the observed dependence on the acidity of the solution was small. The most favourable time for the adsorption process was found to be about 2 h for calcium alginate and 4 h for the other two sorbents.
The application of raw and modified biomass to remove hydrocarbons from wastewater by adsorption is a common practice. A mathematical modeling of biosorption kinetics is a crucial step to optimize the remediation process. In the present study, kinetic studies were carried out to describe the sorption process of crude oilon waste sunflower stalk pith. To increase sorption capacity, the pith surface was modified with polydimethylsiloxane (PDMS) and hydrophobic SiO2 nanoparticles. The maximum loading of sorption for raw and hydrophobized material was 17.76 g/g and 19.62 g/g for crude oil, respectively. The system reached the equilibrium stage after 24 hours. The uptake profiles have been described by the pseudo-first order rate equation and the pseudo-second order rate equation. The calculated results were compared with experimental data and their fit was poor. To predict biosorption kinetics, a new mathematically efficient procedure based on a modified logistic equation was developed. The results indicate that the sunflower pith is an eco-friendly sorbent with significant potential for the removal of crude oil from water phase.
The Pb(II)-resistant bacterium was isolated from heavy metal-contained soils and used as a biosorbent to remove Pb(II). The strain was identified as Enterobacter sp. based on the 16S rRNA sequence analysis. The effect of biosorption properties (pH value, Pb(II) concentration, bacterial concentration and temperature) on Pb(II) was investigated by batch experiments. Results of FTIR and XPS showed that the biosorption process mainly involved some oxygen-containing groups (-OH and -COOH groups). The experimental results and equilibrium data were fitted by pseudo-second-order kinetic model and Langmuir model, respectively. The experimental biosorption isotherms fitted the Langmuir model, and the maximum biosorption capacity was 40.75 mg/g at 298 K. The calculated ΔGо and ΔHо were –4.06 and 14.91(kJ/mol), respectively, which indicated that biosorption process was spontaneous and endothermic. Results show that Enterobacter sp. will be an efficient biosorbent for Pb(II) removal.
Simultaneous adsorption of heavy metals in complex multi metal system is insuffnciently explored. This research gives results of key process parameters optimization for simultaneous removal of Cd(II), Co(II), Cr(III), Cu(II), Mn(II), Ni(II) and Pb(II) from aqueous solution (batch system). New lemon peel-based biomaterial was prepared and characterized by infrared spectroscopy with Fourier transformation (FTIR), scanning electron microscopy (SEM), electron dispersive spectroscopy (EDS), while the quantifi cation of metals was made by atomic absorption spectrometry (AAS). Simultaneous removal of seven metals ions was favorable at pH 5 with 300 mg/50 mL solidliquid phase ratio, within 60 min at room temperature with total obtained adsorption capacity of 46.77 mg g–1. Kinetic modeling showed that pseudo-second order kinetic and Weber-Morris diffusion models best describe the adsorption mechanism of all seven heavy metals onto lemon peel.
The use of guava seeds (GS) and acid-modified guava seeds (MGS) for the removal of Cr(VI) from aqueous solutions was investigated. Batch-type experiments were performed with Cr(VI) aqueous solutions and biosorbents to determine the kinetic and equilibrium sorption parameters. Results indicated that GS and MGS were capable of reducing and remove Cr(VI) from solutions, but the reduction was only observed at some experimental conditions. Infrared analysis showed that several functional groups were involved in the reduction, and biosorption of Cr(VI), particularly alcohol, phenolic, carboxylic, and methoxymethyl structures. The mechanisms of reduction and biosorption depended upon the type of biosorbent, pH, and temperature of the system. The pseudo-second-order kinetic model describes the kinetic sorption data, and the Langmuir-Freundlich (L-F) model describes the isotherm data in most cases. Significantly high total chromium biosorption capacities were obtained. Acid modification of guava seeds improves chromium biosorption performance.
This study deals with utilization of milled stems and leaves of carrot (Daucus carota) for the adsorptive removal of Pb(II) and Cd(II) from the aqueous solution. Carrot was bought in the local grocery, it was dried at the laboratory temperature and milled. Prepared material was analysed by the infrared spectrometry which confirms good structural homogeneity of the sample. Kinetic measurements were performed for estimation of adsorption equilibrium time. Equilibrium of Pb(II) adsorption was established after 6 hours of contact time, equilibrium of Cd(II) adsorption was established after 24 hours of contact time. The isotherms’ measurements were realized with the contact time 24 hours for the estimation of adsorption capacities of the studied sorbent. Adsorption capacities were around 47 mg/g for Cd(II) and 154 mg/g for Pb(II). Changes of pH values of the sorption solutions were negligible but some amount of Ca(II), Mg(II), K(I) and Na(I) ions was released to the solution during adsorption process. Daucus carota stems and leaves exhibit good sorption capacities and they could be utilized for adsorptive removal of Pb(II) and Cd(II) ions from the aqueous solutions.
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Artykuł dotyczy wykorzystania zmielonych łodyg i liści marchwi (Daucus carota) do adsorpcyjnego usuwania Pb (II) i Cd (II) z roztworu wodnego. Marchewkę kupiono w lokalnym sklepie spożywczym, wysuszono w laboratorium i zmielono. Przygotowany materiał analizowano za pomocą spektrometrii w podczerwieni, co potwierdziło dobrą jednorodność strukturalną próbki. Pomiary kinetyczne przeprowadzono w celu oszacowania czasu osiągnięcia równowagi adsorpcji. Równowagę adsorpcji Pb (II) ustalono po 6 godzinach czasu kontaktu, równowagę adsorpcji Cd (II) ustalono po 24 godzinach czasu kontaktu. Pomiary izoterm wykonano z czasem kontaktu 24 godziny w celu oszacowania zdolności adsorpcji badanego sorbentu. Zdolności adsorpcyjne wynosiły około 47 mg / g dla Cd (II) i 154 mg / g dla Pb (II). Zmiany wartości pH roztworów sorpcyjnych były znikome, ale pewna ilość jonów Ca (II), Mg (II), K (I) i Na (I) została uwolniona do roztworu podczas procesu adsorpcji. Łodygi i liście Daucus carota wykazują dobre zdolności sorpcyjne i można je wykorzystać do adsorpcyjnego usuwania jonów Pb (II) i Cd (II) z roztworów wodnych.
The adsorption of Eurozol Navy Blue (ENB) reactive dye was examined using banana peel and sugarcane bagasse powders. Several parameters such as pH, contact time, agitation speed, temperature, initial dye concentration, and adsorbent dosage were considered and their impact on dye adsorption efficiency was evaluated. The removal percentages of ENB dye due to adsorption on banana peel and sugarcane bagasse were 72% and 70%, respectively. Simultaneous dosing of both biosorbents resulted in 68% dye removal. The Langmuir isotherm model was found to fit the adsorption of ENB dye on banana peel and sugarcane bagasse powders. The corresponding maximum adsorption capacities were equal to 24.09, 32.46, and 27.54 mg/g for banana peel powder, sugarcane bagasse powder, and the mixture of adsorbents, respectively.
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The biosorption of lithium from batch systems by Arthrospira (Spirulina) platensis biomass was studied. Adsorption capacity of the biosorbent was investigated as a function of contact time, initial metals concentration and pH values. Lithium content in biomass was determined using Proton Induced Gamma Emission technique. The ability of spirulina biomass for lithium biosorption showed a maximum at the pH = 11. Equilibrium data fitted well with the Langmuir model with maximum adsorption capacity of 1.75 mg/g, while the kinetic data were best described using the pseudo second-order kinetic model. The IR spectrum of the Li-loaded biomass revealed that lithium ions could be primarily bind to –OH, –COOH, –NH, –NH2, and –NH3 groups present on biosorbent surface. Arthrospira platensis biomass could be applied as environmentally friendly sorbent for lithium removal from wastewater.
Chromium in wastewater is classified as one of the dangerous contaminants that require further treatment before being discharged to water body. The concentration of chromium in water body, especially river, has increased as many industries utilize chromium as raw material and then discharge their wastewater without any treatment. Biosorption is one of methods that are widely used to treat heavy metal containing wastewater. Bacteria are the most common microorganisms to be used as heavy metal treatment agent. Azotobacter s8, Bacillus subtilis and Pseudomonas putida had been proven to have a heavy metal resistant capability. The screening test showed that Minimum Inhibitory Concentration (MIC) value of chromium for all bacteria ranged from 100 to 250 mg/L of CrCl3. The chromium biosorption test by bacteria showed that Azotobacter s8 was able to remove 10.53%, and Bacillus subtilis was able to remove 5.68% chromium from 50 mg/L initial concentration, while Pseudomonas putida showed no chromium removal. The chromium biosorption capacity by Azotobacter s8 was 580.08 mg/g and 349.30 mg/g for Bacillus subtilis.
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