Low-cost biogenic waste for phosphate capture from aqueous system

2012 ◽  
Vol 209 ◽  
pp. 170-179 ◽  
Author(s):  
N.A. Oladoja ◽  
A.L. Ahmad ◽  
O.A. Adesina ◽  
R.O.A. Adelagun
Author(s):  
Yue Yin ◽  
Gaoyang Xu ◽  
Linlin Li ◽  
Chunlei Qiao ◽  
Yihua Xiao ◽  
...  

Abstract During sediment remediation, adsorbents addition is an effective technology for the removal of contaminants but the cost is often high. In this study, a low-cost adsorbent, ceramsite that made from contaminated riverbed sediment was synthesized. The Fe-modified ceramsite (FMC) was used as adsorbents to remove arsenate from aqueous solutions and reduce the inorganic arsenic release from contaminated sediments. Kinetic studies showed that chemisorption mainly governed the adsorption process while batch studies yielded theoretical adsorption capacity for arsenate of 10.63 mg/g at pH = 7 condition. Co-existing anions and pH have no significant impact on the adsorption process. In the regeneration studies, 91, 86, and 80% of the adsorption capacity were recovered in 3 cycles. In-situ remediation trials revealed that the addition of the adsorbent to sediment surface significantly reduced the release of inorganic arsenic into aqueous system, with a reduction efficiency of 86%. Furthermore, the species of the arsenic in the surface layer was significantly inactivated from an active state to a stable state. These findings highlight the application of the FMC as a facile and cost-effective adsorbent for containment of arsenic in solutions and sediments, demonstrating that they are highly applicable for practical cases.


2021 ◽  
Vol 46 (4) ◽  
pp. 1-8
Author(s):  
Jessica Costa SILVA ◽  
Luiz Henrique Svintiskas LINO ◽  
Márcia Nieves CARNEIRO DA CUNHA ◽  
Juanize Matias da Silva BATISTA ◽  
Vagne Melo OLIVEIRA ◽  
...  

Internal viscera fish are potential sources of protein biomolecules of biopharmaceutical interest. However, this residue is frequently discarded inappropriately. The possibility to obtain by products of higher added value is a reality. Inside this view attention must be given to processes for the recovery and extraction of target molecules. However, the high cost of processing these residues is one of the obstacles to their reuse; techniques that facilitate their handling and make the process cheaper are desirable, such as extraction in a two-phase aqueous system. Thus, the aim of this study was to extract collagenolytic enzymes from common snook (Centropomus undecimalis) using a two-phase aqueous system (polyethylene glycol/citrate), according to the 24 factorial design, using as variables: molar mass of PEG (MPEG), PEG concentration (CPEG), citrate concentration (CCIT), pH, still, considering purification factor (FP), partition coefficient (K), and yield (Y). The collagenolytic activity of the crude extract was 102.41 U mg-1, after partitioning, was purified 3.91 times (MPEG: 8000; CPEG: 20.0%; CCIT: 20.0% and pH 6.0). Inhibition (U mg-1) was observed in benzamidine (22.51), TLCK (21.05), TPCK (21.29), and PMSF (23.05), signaling to be a serine-protease. The results showed the advantage of this semipurification technique as concerns to the low cost of extraction and purification, adding value to the fishing source material and allocating the residues from its processing to the industry.


2011 ◽  
Vol 306-307 ◽  
pp. 1334-1337 ◽  
Author(s):  
Meng Zhang ◽  
Fu Wei Wan ◽  
Shen Guang Ge ◽  
Jing Hua Yu

We report the synthesis and characterization of a low-cost high-quality CdS quantum dots (QDs).The synthesis was performed in aqueous system. The aqueous CdS colloidal solution was prepared using thioglycollic acid as a capping agent. Zetasizer Nano ZS (Malvern, UK) was employed to characterize the partical size of CdS QDs. The UV-vis and photoluminescence (PL) spectra of samples were systematically characterized (the full width at half maximum was 38 nm). The maximum photoluminescence (PL) quantum yield (QY) was as high as 68.5 %. The fluorescence intensity was enhanced by copper (II). The relative fluorescence intensity was linear to copper (II) concentration over the range 4.0 ×10-6 - 2.8×10-5 g mL-1. The regression equation was ΔIF= 59.07+ 90.57c (c / μg mL-1). The highly monodispersed CdS QDs could be used in many fields.


2021 ◽  
pp. 121-161
Author(s):  
P. Shandilya

The progress of ferrites and ferrites-based nanocomposites has become extensively popular in the field of photocatalytic wastewater treatment. This class of compound exhibit several fascinating properties related with their high stability, low cost, ease of functionalization, and biocompatibility. Ferrites carry outstanding magnetic behavior that helps in their easy recovery from the aqueous system thus reducing the cost. The morphology and various properties such as magnetic, absorption, optoelectronic of magnetic ferrites can be varied and optimize by applying different synthetic routes and reaction conditions. With this background we have briefly presented and reviewed the latest development in the field of photodegradation of aqueous pollutants using ferrites based heterojunction. Especially, the type-II, Z-scheme and S-scheme based heterojunction for enhanced pollutant degradation under the exposure of light are thoroughly describe. Ferrites have inherent potential in water remediation applications hence many examples were consider to impart valuable knowledge to the readers. Nevertheless, the large-scale utilization of these magnetic nanoparticles still needs to be explored. Therefore, the gaps, challenges and future prospective of ferrites nanoparticles are also explained to unveil the un-scrutinized standard of ferrites nanoparticles.


2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Gietu Yirga Abate ◽  
Adugna Nigatu Alene ◽  
Adere Tarekegne Habte ◽  
Desiew Mekuanint Getahun

Abstract Background The release of hazardous synthetic dyes into industrial effluents has emerged as an environmental problem requiring remediation. The present study focused on the preparation of a new and environmentally-friendly material (adsorbent) for the remediation of hazardous dyes from aqueous solution. The low cost adsorbent was prepared from locally available khat (Catha edulis) stem which considered as waste and accumulated on waste disposal areas of Woldia town, Ethiopia. Comprehensive characterization studies were carried out on the bio-adsorbent such as proximate analyses, specific surface area, point of zero charge and FT-IR analysis. Results The proximate analysis shows the prepared adsorbent has very high fixed carbon content (83.65%), which refers to high quality of the adsorbent. The adsorption performance of the prepared activated carbon was optimized by varying operational parameters such as initial dye concentration (10 mg/L), pH (10), dosage (0.5 g), and contact time (60 min). The maximum removal efficiency of the prepared adsorbent at those optimum conditions was 98.8%. The experimental data was tested by most common kinetics and isotherm models. It was observed that the pseudo-second-order kinetic model fits better with good correlation coefficient and the equilibrium data fitted well with the Freundlich isotherm model. Conclusion In summery this study demonstrated that the waste bio sorbent could be employed as an effective and eco-friendly alternative for the cleanup of dye-polluted aqueous system.


2016 ◽  
Vol 1133 ◽  
pp. 542-546 ◽  
Author(s):  
Safoura Daneshfozoun ◽  
Bawadi Abdullah ◽  
M. Azmuddin Abdullah

Oil Palm Empty Fruit Bunch (OPEFB) contributes more than 50% of oil palm biomass wastes in Malaysia. This provides tremendous opportunities for value-added product generation from recycling and utilizing its latent capacity. In this work, the performance of physically-pretreated OPEFB fibers without any chemical treatment for Pb2+ removal from aqueous system was evaluated. Three different size ranges (1-5 cm, 0.5-2 mm and 0.005-0.02 mm) of raw sorbent, pH (4-10) and contact time (2-150 min) for Pb2+ batch adsorption were tested. The kinetic data were evaluated by the pseudo-first-order, pseudo-second-order and intra-particle diffusion model. The experimental data were well described by the pseudo-second-order model with r2=0.997. Adsorption efficiency was size-dependent with about 38% sorption increase at 0.005-0.02 mm, and reached 94% efficiency, achieved 47.49 mg/g capacity with 500 ppm Pb2+ at pH 7.5, in 60 min. The eco-friendly, low cost sorbent can be applied as green, effective adsorbent in waste water remediation.


2020 ◽  
Author(s):  
Gietu yirga Abate ◽  
Adugna Nigatu Alene ◽  
Adere Tarekegne Habte ◽  
Desiew Mekuanint Getahun

Abstract Background: The release of hazardous synthetic dyes into industrial effluents has emerged as an environmental problem requiring remediation. The present study focused on the preparation of a new and environmentally-friendly material (adsorbent) for the remediation of hazardous dyes from aqueous solution. The low cost adsorbent was prepared from locally available khat (Catha edulis) stem which considered as waste and accumulated on waste disposal areas of Woldia town, Ethiopia. Comprehensive characterization studies were carried out on the bio-adsorbent such as proximate analyses, specific surface area, point of zero charge and FT-IR analysis. Results: The proximate analysis shows the prepared adsorbent has very high fixed carbon content (83.65%), which refers to high quality of the adsorbent. The adsorption performance of the prepared activated carbon was optimized by varying operational parameters such as initial dye concentration (10 mg/L), pH (10), dosage (0.5 g), and contact time (60 min). The maximum removal efficiency of the prepared adsorbent at those optimum conditions was 98.8%. The experimental data was tested by most common kinetics and isotherm models. It was observed that the pseudo-second-order kinetic model fits better with good correlation coefficient and the equilibrium data fitted well with the Freundlich isotherm model.Conclusion: In summery this study demonstrated that the waste bio sorbent could be employed as an effective and eco-friendly alternative for the cleanup of dye-polluted aqueous system.


2020 ◽  
Author(s):  
Gietu yirga Abate ◽  
Adugna Nigatu Alene ◽  
Adere Tarekegne Habte ◽  
Desiew Mekuanint Getahun

Abstract Background: The release of hazardous synthetic dyes into industrial effluents has emerged as an environmental problem requiring remediation. The present study focused on the preparation of a new and environmentally-friendly material (adsorbent) for the remediation of hazardous dyes from aqueous solution. The low cost adsorbent was prepared from locally available khat (Catha edulis) stem which considered as waste and accumulated on waste disposal areas of Woldia town, Ethiopia. Comprehensive characterization studies were carried out on the bio-adsorbent such as proximate analyses, specific surface area, point of zero charge and FT-IR analysis. Results: The proximate analysis shows the prepared adsorbent has very high fixed carbon content (83.65%), which refers to high quality of the adsorbent. The adsorption performance of the prepared activated carbon was optimized by varying operational parameters such as initial dye concentration (10 mg/L), pH (10), dosage (0.5 g), and contact time (60 min). The maximum removal efficiency of the prepared adsorbent at those optimum conditions was 98.8%. The experimental data was tested by most common kinetics and isotherm models. It was observed that the pseudo-second-order kinetic model fits better with good correlation coefficient and the equilibrium data fitted well with the Freundlich isotherm model.Conclusion: In summery this study demonstrated that the waste bio sorbent could be employed as an effective and eco-friendly alternative for the cleanup of dye-polluted aqueous system.


2020 ◽  
Author(s):  
Gietu yirga Abate ◽  
Adugna Nigatu Alene ◽  
Adere Tarekegne Habte ◽  
Desiew Mekuanint Getahun

Abstract Background: The release of hazardous synthetic dyes into industrial effluents has emerged as an environmental problem requiring remediation. The present study focused on the preparation of a new and environmentally-friendly material (adsorbent) for the remediation of aqueous media containing dye. The low cost adsorbent was prepared from locally available khat (Catha edulis) stem which considered as waste and accumulated on waste disposal areas of woldia town, Ethiopia. Comprehensive characterization studies were carried out on the bio-adsorbent such as proximate analyses, specific surface area, and Fourier-Transform Infrared (FTIR) spectroscopy (which shows functional groups on adsorbents surface). Results: The proximate analysis shows the prepared adsorbent has very high fixed carbon content (83.65%), which refers to high quality of the adsorbent. The adsorption performance of the prepared activated carbon was optimize by varying operating parameters such as initial dye concentration (10 mg/L), pH (10), dosage (0.5 g), and contact time (60 min). The maximum removal efficiency of the prepared adsorbent at those optimum conditions was 98.8%. The experimental data was tested by most common kinetics and isotherm models. It was observed that the pseudo-second-order kinetic model fits better with good correlation coefficient and the equilibrium data fitted well with the Freundlich isotherm model. Conclusion: In summery this study demonstrated that the waste bio sorbent could be employed as an effective and eco-friendly alternative for the cleanup of dye-polluted aqueous system.


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