scholarly journals Biosorption of toxic metals using freely suspended Microcystis aeruginosa biomass

2014 ◽  
Vol 12 (12) ◽  
pp. 1232-1238 ◽  
Author(s):  
Piotr Rzymski ◽  
Przemysław Niedzielski ◽  
Jacek Karczewski ◽  
Barbara Poniedziałek
Keyword(s):  
Aqueous Solutions ◽  
Microcystis Aeruginosa ◽  
Toxic Metals ◽  
High Efficiency ◽  
Low Cost ◽  
Sorption Material ◽  
Metal Biosorption ◽  
Physico Chemical ◽  
Freely Suspended ◽  
Chemical Conditions

AbstractThis paper describes the potential application of a freely suspended cyanobacterial biomass of Microcystis aeruginosa as a sorption material for toxic metals, cadmium (Cd) and lead (Pb) from aqueous solutions. In order to identify the most suitable conditions for removal of these elements (concentration range: 1–20 mg L−1), the laboratory experiments were carried out during different incubation times (1–48 h) and under various temperatures (10–40°C), pH (5–9) and with or without light irradiance. Competitive biosorption of Cd and Pb was also investigated. We found that M. aeruginosa demonstrates high efficiency in removing both of the studied metals from aqueous solutions. Sorption of Pb occurred, however, more rapidly and effectively, and was less disturbed by changes in physico-chemical conditions. Under pH=7, 25°C and light, the removal rates after 3 h and 6 h of incubation, were 90–100% for Pb and 79.5–100% for Cd, respectively. The co-occurrence of the metals decreased the rate of metal biosorption. Pb was sequestered preferentially over Cd. From the results we conclude that freely suspended M. aeruginosa can constitute a promising low-cost, easy-producible biosorbent material for toxic metals in contaminated wastewater.

scholarly journals Adsorption of Rare Earth Elements from Aqueous Solutions Using Geopolymers

Proceedings ◽  
2018 ◽  
Vol 2 (10) ◽  
pp. 567 ◽  
Author(s):  
Željka Fiket ◽  
Ana Galović ◽  
Gordana Medunić ◽  
Martina Furdek Turk ◽  
Maja Ivanić ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Aqueous Solutions ◽  
High Efficiency ◽  
Low Cost ◽  
Coal Ash ◽  
Industrial Sector ◽  
Efficient Removal ◽  
Model Solutions ◽  
Technology Applications

Rare earth elements, i.e., lanthanides, are important components of many recently developed technology applications. However, their increasing use in the industrial sector, medicine, and agriculture over the last few decades has provided them with the title of “new pollutants”. Different methods are now applied for the removal of various pollutants from wastewaters, whereby the emphasis is placed on adsorption due to its simplicity, high efficiency, and low cost. In the present study, geopolymers prepared from coal ash were examined regarding their capacity for the adsorption of lanthanides from model solutions. The obtained results indicate the efficient removal of lanthanides by prepared geopolymers, depicting them as effective adsorbents for this group of elements.

scholarly journals The Simultaneous Removal of Zinc and Cadmium from Multicomponent Aqueous Solutions by Their Sorption onto Selected Natural and Synthetic Zeolites

Minerals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 343 ◽  
Author(s):  
Bożena Kozera-Sucharda ◽  
Barbara Gworek ◽  
Igor Kondzielski
Keyword(s):  
Aqueous Solutions ◽  
Low Cost ◽  
Environmental Pollutants ◽  
Chemical Properties ◽  
Simultaneous Removal ◽  
Physico Chemical ◽  
Synthetic Zeolites ◽  
Sorption Mechanisms ◽  
Synthetic Aluminosilicate ◽  
Natural And Synthetic

Natural and synthetic aluminosilicate minerals, in particular zeolites, are considered to be very useful in remediation processes, such as purification of waters polluted with heavy metals. That is due to their unique and outstanding physico-chemical properties, rendering them highly efficient, low-cost, and environmentally friendly sorbents of various environmental pollutants. The aim of this study was to examine the sorption capacity of four selected zeolites: A natural zeolite and three synthetic zeolites (3A, 10A, and 13X), towards zinc and cadmium present in multicomponent aqueous solutions, in relation to identified sorption mechanisms. It was stated that synthetic zeolites 3A and 10A were the most efficient in simultaneous removal of zinc and cadmium from aqueous solutions. Additionally, zeolite 10A was demonstrated to be the mineral best coping with prolonged pollution of water with those elements. The mechanism of sorption identified for tested minerals was physisorption.

scholarly journals Magnetic Fe3O4@Chitosan Carbon Microbeads: Removal of Doxycycline from Aqueous Solutions through a Fixed Bed via Sequential Adsorption and Heterogeneous Fenton-Like Regeneration

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Bo Bai ◽  
Xiaohui Xu ◽  
Changchuan Li ◽  
Jianyu Xing ◽  
Honglun Wang ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
High Efficiency ◽  
Low Cost ◽  
Fixed Bed ◽  
Breakthrough Curves ◽  
Chitosan Hydrogel ◽  
Fixed Bed Column ◽  
Adsorptive Removal ◽  
Sequential Adsorption ◽  
Cracking Process

The adsorptive removal of antibiotics from aqueous solutions is recognized as the most suitable approach due to its easy operation, low cost, nontoxic properties, and high efficiency. However, the conventional regeneration of saturated adsorbents is an expensive and time-consuming process in practical wastewater treatment. Herein, a scalable adsorbent of magnetic Fe3O4@chitosan carbon microbeads (MCM) was successfully prepared by embedding Fe3O4 nanoparticles into chitosan hydrogel via an alkali gelation-thermal cracking process. The application of MCM composites for the adsorptive removal of doxycycline (DC) was evaluated using a fixed-bed column. The results showed that pH, initial concentration, flow rate, and bed depth are found to be important factors to control the adsorption capacity of DC. The Thomas and Yoon-Nelson models showed a good agreement with the experimental data and could be applied for the prediction of the fixed-bed column properties and breakthrough curves. More importantly, the saturated fixed bed can be easily recycled by H2O2 which shows excellent reusability for the removal of doxycycline. Thus, the combination of the adsorption advantage of chitosan carbon with catalytic properties of magnetic Fe3O4 nanoparticles might provide a new tool for addressing water treatment challenges.

Assessment of Signal Peptides to Optimize Interleukin 2 (IL-2) Folding and Expression

2019 ◽  
Vol 16 (3) ◽  
pp. 188-198 ◽  
Author(s):  
Narges Nazifi ◽  
Mojtaba Tahmoorespur ◽  
Mohammad Hadi Sekhavati ◽  
Alireza Haghparast ◽  
Mohammad Ali Behroozikhah
Keyword(s):  
Cellular Localization ◽  
High Efficiency ◽  
Low Cost ◽  
Expression System ◽  
Interleukin 2 ◽  
Signal Peptides ◽  
Gram Negative Bacteria ◽  
E Coli ◽  
Secretion Pathway ◽  
Physico Chemical

Background:Using a bacterial expression system such as Escherichia coli (E. coli) is very common for protein expression because of its simplicity, low cost and high efficiency.Objective:In order to express proteins that contain di-sulfide bands, an oxidative space such as the periplasmic environment of the bacteria is required. Therefore, a leader sequence which named Signal Peptide (SP) is needed to direct recombinant protein to fold in periplasmic space. Interleukin-2 (IL-2) is a prominent cytokine which known as growth factor for T-cells and typically produced by a variety of immune cells that stimulate and regulate inflammatory and immune responses.Methods:This study was designed to predict the best signal peptides to express IL-2 in E. coli. To predict the best signal peptides for the expression of IL-2 in Gram-negative bacteria (E. coli), forty-five sequences of SPs were extracted from data base. Some most important details such as n, h and c regions of signal peptides and their probability were studied through the signalP software. </P><P> Afterwards, physico–chemical features of SPs were analyzed by Portparam and Solpro tools. Finally, secretion-pathway and sub-cellular localization sites were evaluated by PRED-TAT and ProtcompB softwares.Results:At the end of the in-silico analyzes, it was determined that ccmH, PelB, traU, yohN, lolA, yhcN are the most reliable SPs, respectively, with highest score and best performing to express the IL-2 protein in E. coli.

scholarly journals The Prospects of Utilizing the Modified Sorption Material to Intensify Purification of Waste Water from Electroplating Production

2019 ◽  
pp. 182-191
Author(s):  
Olga G. Dubrovskaya ◽  
Vladimir A. Kulagin ◽  
Anatoly I. Matyushenko ◽  
Anastasiya G. Bobrik
Keyword(s):  
Heavy Metals ◽  
High Efficiency ◽  
Negative Impact ◽  
Low Cost ◽  
Economic Feasibility ◽  
Hazardous Substances ◽  
Industrial Enterprises ◽  
Sorption Material ◽  
Service Water ◽  
Degree Of Extraction

One of the sources of environmental pollution with hazardous substances, primarily heavy metals, is the electroplating industry. The prevention of pollution of water bodies with wastewater containing heavy metal ions is closely related to reducing the consumption of fresh water for the technological needs of production and to reducing the amount of effluent. One of the solutions to this problem is to create low-waste and waste-free environmentally safe technological processes of wastewater treatment using treated effluents in the recirculation system, which reduces the negative impact on the environment. The results of studying the sorption properties of the natural modified mineral Akdolit-Gran prove a high efficiency of this sorption filling when conditioning electroplating shop effluents contaminated with a complex of heavy metals. Taking into account a relatively low cost of this natural mineral, Akdolit-Gran has the advantages in terms of its economic feasibility, plus the high degree of extraction of metals using this sorbent together with its low consumption allows designing recirculation systems for industrial enterprises meeting the requirements for physical and chemical parameters of service water

scholarly journals Adsorption of Cr(Vi) Ion from Aqueous Solutions by Solid Waste of Potato Peels

2017 ◽  
Vol 5 (3) ◽  
pp. 254 ◽  
Author(s):  
Nidhal M. Sher Mohammed ◽  
Haydar A. Mohammad Salim
Keyword(s):  
Aqueous Solutions ◽  
Metal Ion ◽  
High Efficiency ◽  
Low Cost ◽  
Ion Concentration ◽  
Potato Peel ◽  
Order Model ◽  
Experimental Conditions ◽  
Langmuir Adsorption ◽  
Potato Peels

Pollution of wastewater with heavy metal has always been a serious problem to the environment. Chromium is considered one of the most noxious heavy metals. Adsorption is now reorganized as an alternative technology of defence for chromium removal due to local availability, technical efficiency and cost effectiveness. Potato peel powder can be used as a low cost biosorbent to remove hexavalent chromium from aqueous solutions under various experimental conditions. Different parameters including equilibrium contact time, initial metal ion concentration, potato peel dose, pH and temperature were studied through a number of batch sorption experiments. Both the Langmuir and Freundlich were found to fit the adsorption isotherm of Cr (VI) ion onto potato peel. The Langmuir adsorption capacity was found to be 1.97 mg/g while Freundlich constants including Kf and n were 1.57 and 2.5, respectively. The adsorption kinetic was found to be more fit with the pseudo-first order model. This study showed a high efficiency of potato peel for the biosorption of Cr (VI) ion from aqueous solutions.

Adsorption of cefixime from aqueous solutions using modified hardened paste of Portland cement by perlite; optimization by Taguchi method

2016 ◽  
Vol 74 (5) ◽  
pp. 1069-1078 ◽  
Author(s):  
Mohammad Hossein Rasoulifard ◽  
Soghra Khanmohammadi ◽  
Azam Heidari
Keyword(s):  
Portland Cement ◽  
Aqueous Solutions ◽  
High Efficiency ◽  
Low Cost ◽  
Cost Effective ◽  
Isotherm Models ◽  
Batch Adsorption ◽  
Affecting Factors ◽  
Effective Removal ◽  
Removal Technique

In the present study, we have used a simple and cost-effective removal technique by a commercially available Fe-Al-SiO2 containing complex material (hardened paste of Portland cement (HPPC)). The adsorbing performance of HPPC and modified HPPC with perlite for removal of cefixime from aqueous solutions was investigated comparatively by using batch adsorption studies. HPPC has been selected because of the main advantages such as high efficiency, simple separation of sludge, low-cost and abundant availability. A Taguchi orthogonal array experimental design with an OA16 (45) matrix was employed to optimize the affecting factors of adsorbate concentration, adsorbent dosage, type of adsorbent, contact time and pH. On the basis of equilibrium adsorption data, Langmuir, Freundlich and Temkin adsorption isotherm models were also confirmed. The results showed that HPPC and modified HPPC were both efficient adsorbents for cefixime removal.

Biosorpsi Ion Zink (II) dari Larutan Berair menggunakan Kulit Pisang (Musa paradisiaca) sebagai Low-cost Biosorbent

2019 ◽  
Vol 2 (2) ◽  
Author(s):  
Edi Nasra ◽  
Desy Kurniawaty ◽  
Bahrizal ◽  
Reni Puspita Sari
Keyword(s):  
Particle Size ◽  
Optimum Condition ◽  
Aqueous Solutions ◽  
Flow Rate ◽  
Toxic Metals ◽  
Low Cost ◽  
Initial Concentration ◽  
Musa Paradisiaca ◽  
Column Method ◽  
Good Potential

Adsorpsi Zn (II) daril arutan berair menggunakan kulit pisang (Musa paradisiaca) sebagai biosorben telah dikaji dengan menggunakan metode kolom. Proses adsorpsi dikaji terhadap beberapa parameter,seperti pH, konsentrasil arutan Zn (II) mula-mula, massa biosorben, ukuran partikel biosorben dan laju alir. Kondisi optimum proses adsorpsi Zn (II) dengan biosorben kulit pisang berlangsung pada pH 3 dengan konsentrasi larutan Zn (II) mula-mula 500 mg/L, massa biosorben 0,6 g, ukuran partikel biosorben 250 µm dan laju alir 2 mL/min memiliki kapasita sadsorpsi 7,8567 mg/g. Berdasarkan hasil penelitian dapat disimpulkan bahwa kulit pisang, sebagai limbah, memiliki potensi yang baik sebagai biosorben untuk menyerap logam berat, seperti seng (Zn) dari perairan.   The removal of Zn (II) from aqueous solutions using banana (Musa paradisiaca) shell as biosorbent has been studied with column method. The parameters of adsorption such as pH, initial concentration, biosorbent dose, particle size and flow rate were investigated. The optimum condition was at pH=3, concentration 500 mg/l, biosorbent dose 0,6 g, 250 μm particle size and 2 ml/min flow rate with adsorption capacity 7,8567 mg/g. This study concluded that banana shell, a waste material, have good potential as biosorbent to remove toxic metals like zink from water.

scholarly journals Low-Cost and Eco-Friendly Hydroxyapatite Nanoparticles Derived from Eggshell Waste for Cephalexin Removal

Separations ◽  
2022 ◽  
Vol 9 (1) ◽  
pp. 10
Author(s):  
Huda S. Alhasan ◽  
Nadiyah Alahmadi ◽  
Suhad A. Yasin ◽  
Mohammed Y. Khalaf ◽  
Gomaa A. M. Ali
Keyword(s):  
Aqueous Solutions ◽  
High Efficiency ◽  
Low Cost ◽  
Chemical Precipitation ◽  
Solution Temperature ◽  
Order Kinetic ◽  
Experimental Conditions ◽  
Removal Process ◽  
The Impact ◽  
Eggshell Waste

This work describes the hydroxyapatite nanoparticle (HAP) preparation from eggshell waste and their application as an adsorbent for Cephalexin (Ceph) antibiotic removal from aqueous solutions. Chemical precipitation with phosphoric acid was used to evaluate the feasibility of calcium oxide for HAP preparation. The structural properties of HAP were characterized by X-ray diffraction, which revealed the formation of the hydroxyapatite crystalline phase formation. In addition, transmitting electron spectroscopy showed an irregular shape with a variation in size. The impact of various experimental conditions on the removal efficiency such as the solution’s pH, contact time, HAP mass, solution temperature, and Ceph concentration were studied. Experimental data showed that HAP could remove most Ceph species from aqueous solutions within 1 h at pH = 7 with 70.70% adsorption efficiency utilizing 50 mg of the HAP. The removal process of Ceph species by HAP was kinetically investigated using various kinetic models, and the results showed the suitability of the pseudo-second-order kinetic model for the adsorption process description. Moreover, the removal process was thermodynamically investigated; the results showed that the removal was spontaneous endothermic and related to the randomness increase. The data confirmed that HAP had high efficiency in removing Ceph antibiotics from an aqueous solution.

Influence of MBE Growth Conditions on Dislocation Densities of GaAs/Ge Epilayers Grown on Silicon Substrates

1985 ◽  
Vol 43 ◽  
pp. 364-365
Author(s):  
K.M. Hones ◽  
P. Sheldon ◽  
B.G. Yacobi ◽  
A. Mason
Keyword(s):  
High Efficiency ◽  
Lattice Mismatch ◽  
Low Cost ◽  
Growth Conditions ◽  
Nonradiative Recombination ◽  
Device Structure ◽  
Si Substrates ◽  
Transmission Electron ◽  
Dislocation Densities ◽  
Dislocation Type

There is increasing interest in growing epitaxial GaAs on Si substrates. Such a device structure would allow low-cost substrates to be used for high-efficiency cascade- junction solar cells. However, high-defect densities may result from the large lattice mismatch (∼4%) between the GaAs epilayer and the silicon substrate. These defects can act as nonradiative recombination centers that can degrade the optical and electrical properties of the epitaxially grown GaAs. For this reason, it is important to optimize epilayer growth conditions in order to minimize resulting dislocation densities. The purpose of this paper is to provide an indication of the quality of the epitaxially grown GaAs layers by using transmission electron microscopy (TEM) to examine dislocation type and density as a function of various growth conditions. In this study an intermediate Ge layer was used to avoid nucleation difficulties observed for GaAs growth directly on Si substrates. GaAs/Ge epilayers were grown by molecular beam epitaxy (MBE) on Si substrates in a manner similar to that described previously.

Sign in / Sign up

Export Citation Format

Share Document