scholarly journals Removal of Cadmium Ions from Aqueous Solutions Using Flax Seeds as an Adsorbent

2019 ◽  
Vol 12 (4) ◽  
pp. 1-8
Author(s):  
Nidaa Adil Jasim ◽  
Tamara Kawther Hussein

Removal of Cd(II) from  aqueous solution through adsorption using flax seeds was studied. Adsorption parameters such as pH, adsorbent particle size, adsorbent dosages, and initial concentrations of metal ions were studied. All experiments were conducted at room temperature. Langmuir and Freundlich adsorption isotherm models were applied to describe the quantitative uptake of Cd(II) ions by adsorbent. The results show that the maximum adsorption removal reach to 77 %   for Cd (II) onto flax seeds, at optimum operating conditions: pH of 5, particle size of 75µm, adsorbent dosage of 2 g/100 ml and metal concentration of  5 mg/L . The equilibrium adsorption data for Cd(II) were better fitted to  Freundlich adsorption isotherm model than Langmuir. The study concludes that the use of flax seeds as an economic and locally adsorbent for removing Cd(II) from polluted solution is effective. Thus offering a low cost material show potential use it to remove heavy metals.

2012 ◽  
Vol 9 (3) ◽  
pp. 1389-1399 ◽  
Author(s):  
R. Hema Krishna ◽  
A. V. V. S. Swamy

The powder of mosambi fruit peelings (PMFP) was used as an adsorbent for the removal of heavy metal like Cr (VI) from aqueous solutions was studied using batch tests. The influence of physico-chemical key parameters such as the initial metal ion concentration, pH, agitation time, adsorbent dosage, and the particle size of adsorbent has been considered in batch tests. Sorbent ability to adsorb Cr (VI) ions was examined and the mechanism involved in the process investigated. The optimum results were determined at an initial metal ion concentration was 10 mg/lit, pH=2, agitation time – 60 min, an adsorbent dose (150 mg/50 ml) and the particle size (0.6 mm). The % adsorption, Langmuir constants [Q0=7.51(mg/g) and b=1.69(mg/lit)] Freundlich constant(Kf=2.94), Lagergren rate constants (Kad(min-1)=5.75 x 10-2) for [Cr(VI)] 10 mg/lit were determined for the adsorption system as a function of sorbate concentration. The equilibrium data obtained were tested using Langmuir, Freundlich adsorption isotherm models, and the kinetic data obtained were fitted to pseudo first order model.


2020 ◽  
Vol 32 (3) ◽  
pp. 550-554 ◽  
Author(s):  
Suresh Kumar Patel ◽  
Dhananjay Singh ◽  
Rahul Dev

Arsenic is a ubiquitous and short-term poisoning element, which affects living things. In this study, the removal of arsenic from Gomti river water, Lucknow, Uttar Pradesh integrated modified double slope solar still with activated adsorption bed has been applied. Arsenic contamination in Gomti river at five places were found in the river water in the range of 55.70 ppb to 681.60 ppb, which exceed the maximum permissible limit of 10 ppb as recommended by WHO. Maximum concentration of arsenic in water was found in Mohan Maekins (681.60 ppb). However, mean arsenic concentration in water followed the order: Gaughat (115.37 ppb) < Hanuman setu (297.80 ppb) < Barrage (302.62 ppb) <Kukrail (336.27 ppb) < Mohan Maekins (481.89 ppb). The amount of adsorbed arsenic was increased with increasing initial concentration of arsenic. The aim of this study is to develop a low-cost process for the removal of arsenic effectively including the production of potable water. After results, data were analyzed with ICP-MS method and also verified with Langmuir and Freundlich adsorption isotherm models.


2020 ◽  
Vol 10 (2) ◽  
pp. 88-97
Author(s):  
Zafer Ekinci ◽  
Esref Kurdal ◽  
Meltem Kizilca Coruh

Background: Turkey is approximately 72% of the world’s boron sources. Colemanite, tincal, ulexite and pandermite are among the most significant in Turkey. Boron compounds and minerals are widely used in many industrial fields. Objective: The main purpose of this study was to investigate the control of impurities in the boric acid production process using colemanite by carrying out the reaction with a mixture of CO2 and SO2 - water, and determining the appropriate process conditions to develop a new process as an alternative to the use of sulfuric acid. Due to worrying environmental problems, intensive studies are being carried out globally to reduce the amount of CO2 and SO2 gases released to the atmosphere. Methods: The Taguchi method is an experimental design method that minimizes the product and process variability by selecting the most appropriate combination of the levels of controllable factors compared to uncontrollable factors. Results: It was evaluated the effects of parameters such as reaction temperature, solid-to liquid ratio, SO2/CO2 gas flow rate, particle size, stirring speed and reaction time. The optimum conditions determined to be reaction temperature of 45°C; a solid–liquid ratio of 0.083 g.mL−1; an SO2/CO2 ratio of 2/2 mL.s−1; a particle size of -0.354+0 .210 mm; a mixing speed of 750 rpm and a reaction time of 20 min. Conclusion: Under optimum operating conditions, 96.8% of colemanite was dissolved. It is thought that the industrial application of this study will have positive effects on the greenhouse effect by contributing to the reduction of CO2 and SO2 emissions that cause global warming.


2021 ◽  
Vol 2 (2) ◽  
pp. 19-32
Author(s):  
Hawraa Kassem Hami ◽  
Ruba Fahmi Abbas ◽  
Emad Mahmoud Eltayef ◽  
Neda Ibrahim Mahdi

Metal oxides are widely used in adsorption technology as adsorbent surfaces because of their efficiency, low cost and unique physical properties. The aim of this review to clarify the role of aluminium oxide and Nano aluminium oxide in removing some chemicals contain that influence on human health such as dyes, antibiotics, and heavy metals. This paper also includes the affective of some adsorption parameters like pH, contact time, removal percentageand temperature. The Adsorption nature, kinetic adsorption models and isotherm models are also reported here.


2011 ◽  
Vol 675-677 ◽  
pp. 873-876 ◽  
Author(s):  
Ke Qiang Xie ◽  
Zhan Liang Yu ◽  
Wen Hui Ma ◽  
Yang Zhou ◽  
Yong Nian Dai

In this paper, removal of iron from metallurgical grade silicon with pressure leaching is carried out. We investigated the factors such as the concentration of hydrochloric, particle size of raw material ground, temperature, pressure and reaction time, which influenced on the removal of iron. The results show that the optimum operating conditions for pressure leaching in hydrochloride are: acid concentration 4 mol/L, diameter for raw material less than 50 μm, leaching temperature 160 0C,leaching pressure 2.0 MPa, leaching time 2.0 h. The content of iron residual in MG-Si powder was reduced to about 200 ppmw. The removal efficiency of iron is up to 90.90 %.


2013 ◽  
Vol 594-595 ◽  
pp. 207-213
Author(s):  
T.A.T. Mohd ◽  
Nur Hashimah Alias ◽  
Nurul Aimi Ghazali ◽  
A. Azizi ◽  
Idris S. Adeib ◽  
...  

Natural dyes represent a sustainable source of colorants, which are low cost and safer than synthetic dyes, concerning human health. The purpose of this study is to extract Vitex negundo L. leaves using supercritical carbon dioxide extraction and to identify the extracts potential as a dye. The extraction process has been conducted at different operating conditions by varying temperature from 40 to 65°C with an increment of 5°C at 20, 25, and 30 MPa within 60 minutes constant time. The extracts obtained at different conditions were analyzed using Gas Chromatography Mass Spectrometer (GC-MS) to determine the chemical compounds present. Increase of temperature increased the extraction yield, but further increasing the temperature above 50°C has reduced the yield. The effect of pressure gave two different patterns, in which the first one showed the yield kept increasing with pressure (20 to 30 MPa) at 40, 45, 50, and 55°C. The second pattern showed sudden reduction of yield above 25 MPa at another two higher temperatures. The highest extraction yield (13.94 mg/g) was obtained at 30 MPa and 50°C which considered as optimum operating condition. GC-MS analysis showed the presence of several phytochemicals including some flavonoid compounds, which are potential sources of dye.


2012 ◽  
Vol 18 (2) ◽  
pp. 221-231 ◽  
Author(s):  
Jianwei Ren ◽  
Mokgadi Bopape ◽  
Katlego Setshedi ◽  
Jacob Kitinya ◽  
Maurice Onyango

This study explored the feasibility of using magnetic eggshell-Fe3O4 powder as adsorbent for the removal of Pb(II) and Cu(II) ions from aqueous solution. The metal ionsadsorption media interaction was characterized using XRD and FTIR. The effects of contact time, initial concentrations, temperature, solution pH and reusability of the adsorption media were investigated. The metal ions adsorption was fast and the amount of metal ions adsorbed increased with an increase in temperature, suggesting an endothermic adsorption. The kinetic data showed that the adsorption process followed the pseudo-second-order kinetic model. The optimal adsorption pH value was around 5.5 at which condition the equilibrium capacity was 263.2 mg/g for Pb(II) and 250.0 for Cu(II). The adsorption equilibrium data fitted very well to the Langmuir and Freundlich adsorption isotherm models. The thermodynamics of Pb(II) and Cu(II) adsorption onto the magnetic eggshell-Fe3O4 powder indicated that the adsorption was spontaneous. The reusability study has proven that magnetic eggshell-Fe3O4 powder can be employed as a low-cost and easy to separate adsorbent.


Author(s):  
Alessia Valotta ◽  
Manuel C. Maier ◽  
Sebastian Soritz ◽  
Magdalena Pauritsch ◽  
Michael Koenig ◽  
...  

AbstractIn recent years, 3D printing has emerged in the field of chemical engineering as a powerful manufacturing technique to rapidly design and produce tailor-made reaction equipment. In fact, reactors with complex internal geometries can be easily fabricated, optimized and interchanged in order to respond to precise process needs, such as improved mixing and increased surface area. These advantages make them interesting especially for catalytic applications, since customized structured bed reactors can be easily produced. 3D printing applications are not limited to reactor design, it is also possible to realize functional low cost alternatives to analytical equipment that can be used to increase the level of process understanding while keeping the investment costs low. In this work, in-house designed ceramic structured inserts printed via vat photopolymerization (VPP) are presented and characterized. The flow behavior inside these inserts was determined with residence time distribution (RTD) experiments enabled by in-house designed and 3D printed inline photometric flow cells. As a proof of concept, these structured inserts were fitted in an HPLC column to serve as solid inorganic supports for the immobilization of the enzyme Phenolic acid Decarboxylase (bsPAD), which catalyzes the decarboxylation of cinnamic acids. The conversion of coumaric acid to vinylphenol was chosen as a model system to prove the implementation of these engineered inserts in a continuous biocatalytic application with high product yield and process stability. The setup was further automated in order to quickly identify the optimum operating conditions via a Design of Experiments (DoE) approach. The use of a systematic optimization, together with the adaptability of 3D printed equipment to the process requirements, render the presented approach highly promising for a more feasible implementation of biocatalysts in continuous industrial processes.


2018 ◽  
Vol 877 ◽  
pp. 13-19
Author(s):  
Bhargavi Gunturu ◽  
Geethalakshmi Ramakrishnan ◽  
Renganathan Sahadevan

In the present study, the efficiency of biosorbent derived form Pongamiapinata to remove a basic textile dye Methylene Blue from an aqueous solution was evaluated in batch system. The influence of adsorption parameters such as biosorbent dosage (0.2-1.0g/L), PH (2-10) and initial dye concentration (30-110 mg/L) on the biosorption process was studied. It was noticed that adsorbent dosage has negative effect on dye uptake, could be due to reduced mass transfer rate of dye on to adsorbent. High equilibrium uptake was observed at PH 8. However, initial dye concentration has shown linear relationship with dye uptake. As the dye concentration increases, the number of dye molecules available to be adsorbed on to adsorbent surface increases. Equilibrium isotherms for the adsorption of methylene blue was analyzed through Langmuir and Freundlich isotherm models. The data best fit with Freundlich model than Langmuir isotherm model, suggesting the adsorption was by multilayer mechanism. Maximum adsorption capacity (Q ̊) was found to be 40.49mg/g. It can be concluded from the study that the adsorbent derived from P.pinnata can be a potential low cost competent of activated carbon for textile dyes removal.


2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Michael Berger ◽  
Madeline Karod ◽  
Jillian L. Goldfarb

Abstract Designing sustainable products requires a holistic consideration of issues at the Food-Energy-Water Nexus. One of the world’s greatest challenges is to insure clean water access for all inhabitants. Across the globe, communities often suffer from metal contamination in their water. We must develop low-cost, sustainable materials to treat this contamination, without putting undue stress on other systems. Biomass-based carbon adsorbents are often touted as one potential solution, but to be sustainable the biomass must be locally sourced, not grown on land that could be used to cultivate food, not require extensive water to grow, and not need undue amounts of energy to process. In this laboratory investigation, students were challenged to use a locally available, problematic biomass – phragmites, an invasive species in the Muddy River in Boston, Massachusetts – to develop a green adsorbent to remove metals from water. Specifically, students focused on the removal of manganese, as it is a local problem for several Massachusetts communities. Students activated the phragmites biomass using a room and low (40 °C) temperature KOH treatment, which opened the porous network of the reed to enable adsorption of Mn+2 upwards of 8 mg/g of biomass. In doing this experiment, students were exposed to the concept of adsorption, a separation process not often covered in the traditional chemistry curriculum. Students gained experience in performing adsorption isotherm experiments using atomic adsorption spectroscopy and UV–Vis spectrophotometry and learned to analyze data within adsorption isotherm models. Finally, students made connections between their laboratory data and adsorption theory, and how this data can be used to design greener materials to address environmental issues.


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