Natural Adsorbent Research Papers - Academia.edu (original) (raw)

MgO nanopowders were synthesised via a simple and " greener " route using Carica papaya leaf extract at 500 • C. The bio-derived MgO nanopowders (MgONPs) were characterised by Brunauer–Emmett–Teller (BET), differential thermal and thermogravimetric (DTA-TGA) analysis, powder X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) equipped with an energy-dispersive spectroscopy (EDS). The COD and BOD reduction efficiency of the MgO—NPs was evaluated in the presence of raw and simulated tannery wastewater. Under optimum conditions, the COD of raw tannery wastewater reduced from 2725.9 mg/L to 126.5 mg/L and BOD from 1899.5 mg/L to 104.5 mg/L in a batch system. Also, the turbidity was reduced from the initial concentration of 588 NTU to a level of 98 NTU within 120 min. Impressively, 93.5% COD reduction and 96.9% BOD reduction were obtained by the fixed-bed system. The spent MgO was regenerated and reused several times without significant loss of capacity. Hence, the bio-derived MgO nanopowders offered potential benefits for BOD and COD removal from tannery wastewater.

This paper reviews the synthesis and the absorbing properties of the wide variety of porous sorbent materials that have been studied for application in the removal of organics, particularly in the area of oil spill cleanup. The discussion is especially focused on hydrophobic silica aerogels, zeolites, organoclays and natural sorbents many of which have been demonstrated to exhibit (or show potential to exhibit) excellent oil absorption properties. The areas for further development of some of
these materials are identified.

- by J. THEO KLOPROGGE
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- Oil Spill, Porous Materials, Inorganic Porous Materials, Zeolites

Background and purpose: Generated dye wastewater by the textile industry is usually toxic, non-biodegradable and resistant in the environment. Eggshell is one of the inexpensive material and for the reason the vesicular structures can be used as a proper adsorbent for pollutants removal. The aim of this study is to investigate the efficiency of eggshell for removal of acid orange 2 dye from aqueous solution. Materials and Methods: In the experimental study was determined the efficacy of variant variables such as contact time (15, 30, 60, 90 and 120 min), pH (3, 7 and 11), adsorbent dose (10, 25, 50 and 75 g/L), and initial dye concentration (25, 50 and 100 mg/L). The concentration of dye by spectrophotometer ultraviolet/visible in the wavelength 483 nm was examined. Results: The results showed that with increasing contact time and adsorbent dose, the dye removal efficiency was increased, but with increasing pH and initial dye concentration the removal efficiency was decreased. The maximum of removal efficiency of acid orange 2 dye got in the optimum pH: 3, contact time: 90 min, adsorbent dose: 50 g/L and initial dye concentration: 25 mg/L. Adsorption of acid orange 2 dye (R 2 = 0.87) follow the Freundlich isotherm. Conclusion: Eggshells can be used as an inexpensive and effective adsorbent for the removal of acid orange 2 dye. [Yari AR, Majidi Gh, Tanhaye Reshvanloo M, Ansari M, Nazari Sh, *Emami Kale Sar M, et al. Using Eggshell in Acid Orange 2 Dye Removal from Aqueous Solution. IJHS 2015; 3(2): 38-45] http://jhs.mazums.ac.ir

- by Grzegorz Rzepa
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- Sorbents, Heavy metals, Natural Adsorbent, Bog iron

A solution to the problems associated with low efficiency of purification of arsenic-contaminated water and/or high installation costs may be the use of adsorption process and application of bog iron ores (RD) as an adsorbent. The aim of this study is to determine the sorption efficiency of RD with regards to arsenic and zinc, to verify the obtained results in flow systems and to investigate the chemical stability of the adsorbent. Based on the obtained results, it was found that granular bog iron ores (gRD) are able to efficiently purification of arsenic contaminated waters, and the adsorption column module enables reduction of arsenic content in waters of less than 100 μg/L. This paper demonstrates that gRD have high application potential and can be successfully used in technologies dedicated to the removal of heavy metals and arsenic from contaminated waters.

- by Grzegorz Rzepa
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- Arsenic, Sorbents, Adsorption, Adsorbents
- by ایمان عابدی
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- Carbon, Adsorption, Waste Water, Natural Adsorbent

Titania dispersed on dealuminatedClinoptilotile (TiO2/HCP) was synthesized and characterized by
Scanning Electron Microscope (SEM). Supporting characterization techniques reveals partly
dispersion of TiO2 within the cavities of dealuminated Clinoptilotile (HCP) and TiO2 exist as
nanoparticles or clusters on the HCP surface ascribed to lower loading of TiO2. The photocatalytic
degradation of methyl orange solution was conducted under UV-irradiation in the presence of
TiO2/HCP. The photocatalytic degradation of methyl orange in the presence of the photocatalyst
was optimized at lower loading of TiO2, at a lower initial dye concentration (30 ppm), calcination
temperature of 873K and nitrate ion accelerates degradation activities of methyl orange. Kinetic
studies depict the photocatalytic degradation of methyl orange follows the pseudo-first order
reaction.