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Full-Text Articles in Physical Sciences and Mathematics
Preparation And Characterization Of Chemically-Modified Biomaterials And Their Application As Adsorbents Of Penicillin G, Jesie Silva, Lizebel Morante, Tesfamichael Demeke, Jacqueline Baah-Twum, Abel E. Navarro
Preparation And Characterization Of Chemically-Modified Biomaterials And Their Application As Adsorbents Of Penicillin G, Jesie Silva, Lizebel Morante, Tesfamichael Demeke, Jacqueline Baah-Twum, Abel E. Navarro
Publications and Research
The prevalence of antibiotics in water creates microbial resistance and has a negative impact on the ecosystem. Biomaterials such as spent tea leaves are rich in functional groups and are suitable for chemical modification for diverse applications. This research proposes the use of spent tea leaves of chamomile (CM), green tea (GT), and peppermint (PM) as structural scaffolds for the incorporation of carboxyl, sulfonyl, and thiol groups to improve the adsorption of Penicillin G (Pe). Adsorbents characterization reported a higher number of acidic functional groups, mainly in thiolated products. Scanning electron microscopy (SEM) analysis showed changes on the surfaces of …
Bioremoval Of Phenol From Aqueous Solutions Using Native Caribbean Seaweed, Abel E. Navarro, Anibal Hernandez-Vega, Md Emran Masud, Loretta M. Roberson, Liz M. Diaz-Vázquez
Bioremoval Of Phenol From Aqueous Solutions Using Native Caribbean Seaweed, Abel E. Navarro, Anibal Hernandez-Vega, Md Emran Masud, Loretta M. Roberson, Liz M. Diaz-Vázquez
Publications and Research
Among several Puerto Rican algae, Sargassum sp. (SG) and Chaetomorpha (CM) showed the highest phenol adsorption capacity from aqueous solutions and were used in optimized adsorption batch experiments at room temperature. The effects of pH, adsorbent dose, phenol concentration, salinity and presence of interfering substances were evaluated. Initial solution pH exhibited a strong effect, mainly on the phenol aqueous chemistry; showing the maximum adsorption at pH 10. Sorption isotherm results were modelled according to the Langmuir, Tempkin and Freundlich equations. Isotherm modelling indicated a maximum adsorption capacity (qmax) of 82.10 and 17.7 mg of phenol per gram of SG and …
Comparative Sorption Of Methylene Blue Onto Hydrophobic Clays, Alvaro D. Sponza, Natalia J. Fernandez, David Yang, Karla A. Ortiz, Abel E. Navarro
Comparative Sorption Of Methylene Blue Onto Hydrophobic Clays, Alvaro D. Sponza, Natalia J. Fernandez, David Yang, Karla A. Ortiz, Abel E. Navarro
Publications and Research
Chemical modifications of clay to remove methylene blue (MB) from aqueous solutions at room temperature were compared. Natural bentonite (NC) was modified by cation exchange with hexadecyltrimethylammonium chloride (HC), bencyltriethylammonium chloride (BC), and tetramethylammonium chloride (TC) to reverse the surface polarity of the hydrophilic bentonite. The adsorption of MB was studied and fitted by the adsorption theories of Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin. Equilibrium parameters were calculated, indicating that chemical modification did not improve the adsorption, due to the electrostatic adsorption mechanism. Specific surface area was determined, reporting the following trend: NC > TC > BC > HC. Isotherms show that TC is …
Decolorization Of Hair Dye By Lignocellulosic Waste Materials From Contaminated Waters, Habib Zahir, Michelle Naidoo, Rada-Mayya Kostadinova, Karla A. Ortiz, Rosario Sun-Kuo, Abel E. Navarro
Decolorization Of Hair Dye By Lignocellulosic Waste Materials From Contaminated Waters, Habib Zahir, Michelle Naidoo, Rada-Mayya Kostadinova, Karla A. Ortiz, Rosario Sun-Kuo, Abel E. Navarro
Publications and Research
Basic yellow 57 (BY57) was chosen as a model hair dye due to its prevalence in cosmetics wastewaters. This study proposes the use of lignocellulosic materials like spent tea leaves of peppermint (PM), chai tea (CT), and chamomile (CM) as raw adsorbents for the removal of BY57 from contaminated solutions. Batch adsorption experiments were carried out at room temperature to achieve the maximum adsorption capacity. Results indicate that the highest removal is achieved at pH 6–8, with a minimum adsorbent mass of 75 mg and in the absence of salinity, crowding agents and heavy metals. Adsorption equilibria were modeled according …