scholarly journals Preparation and Characterization of Biochar Derived from Agricultural By-Products for Dye Removal

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Phuong Thu Le ◽  
Huyen Thuong Bui ◽  
Duy Ngoc Le ◽  
Thi Hue Nguyen ◽  
Le Anh Pham ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Dye Adsorption ◽  
Textile Wastewater ◽  
High Specific Surface Area ◽  
Sem Images ◽  
Raman Analysis ◽  
Graphene Layers ◽  
Langmuir And Freundlich Models ◽  
By Products

In this study, biochar was derived from the agricultural by-products coconut coir (BC1) and rice husk (BC2) activated with NaOH 25%. This material was characterized through analytical methods such as SEM images, XRD, FTIR, and Raman. Analysis results indicated that the carbon structure carbon is amorphous and with many graphene layers. A high specific surface area was detected with 364.22 m2.g-1 for BC1 and 329.71 m2.g-1 for BC2 with many meso and micropores when analyzed by N2 and CO2 adsorption. The material also showed anionic and cationic dye adsorption capacity for textile wastewater following both Langmuir and Freundlich models where BC2 had better max adsorption capacity compared to BC1, 6.519 mg.g-1 for MO and 8.612 mg.g-1 for MB.

Tea Waste: A New Adsorbent for the Removal of Reactive Dyes from Textile Wastewater

2013 ◽  
Vol 803 ◽  
pp. 26-29 ◽  
Author(s):  
Antonio Zuorro ◽  
Maria Laura Santarelli ◽  
Roberto Lavecchia
Keyword(s):  
Low Cost ◽  
Dye Adsorption ◽  
Reactive Dyes ◽  
Textile Wastewater ◽  
Tea Leaves ◽  
Thermally Activated ◽  
Reactive Blue 19 ◽  
Reactive Green 19 ◽  
Spent Tea Leaves

Spent tea leaves (STL), a valueless waste produced during the manufacturing of tea beverages, were investigated as a potential low-cost adsorbent for the removal of the azo dyes Reactive Blue 19 (RB19), Reactive Red 120 (RR 120), Reactive Violet 5 (RV5) and Reactive Green 19 (R19) from wastewater. Untreated STL showed very low removal efficiency (< 7%), while a significant increase in dye adsorption was observed when they were thermally activated. Heating STL to 300 °C for 1 hour resulted in removal efficiencies ranging from 68.5 to 98.4%. Characterization of the waste by FTIR and TG/DTA indicated that major structural and/or chemical changes of the cellulose and hemicellulose components of STL occurred during heating.

Development and Characterization of Amine-Clay Hybrid Adsorbents for CO2 Capture

2016 ◽  
Vol 1133 ◽  
pp. 547-551 ◽  
Author(s):  
Ali E.I. Elkhalifah ◽  
Mohammad Azmi Bustam ◽  
Azmi Mohd Shariff ◽  
Sami Ullah ◽  
Nadia Riaz ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Surface Area ◽  
Surface Properties ◽  
Molar Mass ◽  
Adsorption Ability ◽  
Stepwise Increase ◽  
Inverse Effect ◽  
Bet Method ◽  
Sodium Form

The present work aims at a better understanding of the influences of the intercalated mono-, di- and triethanolamines on the characteristics and CO2 adsorption ability of sodium form of bentonite (Na-bentonite). The results revealed that the molar mass of intercalated amines significantly influenced the structural and surface properties as well as the CO2 adsorption capacity of Na-bentonite. In this respect, a stepwise increase in the d-spacing of Na-bentonite with the molar mass of amine was recorded by XRD technique. However, an inverse effect of the molar mass of amine on the surface area was confirmed by BET method. CO2 adsorption experiments on amine-bentonite hybrid adsorbents showed that the CO2 adsorption capacity inversly related to the molar mass of amine at 25 ͦC and 101 kPa. Accordingly, Na-bentonite modified by monoethanolammonium cations adsorbed as high as 0.475 mmol CO2/g compared to 0.148 and 0.087 mmol CO2/g for that one treated with di- and triethanolammonium cations, respectively.

scholarly journals Analytical Characterization of Water-Soluble Constituents in Olive-Derived By-Products

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1299
Author(s):  
Pablo Doménech ◽  
Aleta Duque ◽  
Isabel Higueras ◽  
José Luis Fernández ◽  
Paloma Manzanares
Keyword(s):  
Olive Tree ◽  
Mediterranean Area ◽  
Water Soluble ◽  
Olive Pomace ◽  
Olive Leaves ◽  
Olive Stone ◽  
Olive Trees ◽  
Tree Pruning ◽  
By Products

Olive trees constitute one of the largest agroindustries in the Mediterranean area, and their cultivation generates a diverse pool of biomass by-products such as olive tree pruning (OTP), olive leaves (OL), olive stone (OS), and extracted olive pomace (EOP). These lignocellulosic materials have varying compositions and potential utilization strategies within a biorefinery context. The aim of this work was to carry out an integral analysis of the aqueous extractives fraction of these biomasses. Several analytical methods were applied in order to fully characterize this fraction to varying extents: a mass closure of >80% was reached for EOP, >76% for OTP, >65% for OS, and >52% for OL. Among the compounds detected, xylooligosaccharides, mannitol, 3,4-dihydroxyphenylglycol, and hydroxytyrosol were noted as potential enhancers of the valorization of said by-products. The extraction of these compounds is expected to be more favorable for OTP, OL, and EOP, given their high extractives content, and is compatible with other utilization strategies such as the bioconversion of the lignocellulosic fraction into biofuels and bioproducts.

Dye Adsorption Capacity of MoS2 Nanoflakes Immobilized on Poly(lactic acid) Fibrous Membranes

2021 ◽  
Author(s):  
Rodrigo Schneider ◽  
Murilo H. M. Facure ◽  
Augusto D. Alvarenga ◽  
Paulo A. M. Chagas ◽  
Danilo M. dos Santos ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Adsorption Capacity ◽  
Dye Adsorption ◽  
Poly Lactic Acid ◽  
Fibrous Membranes

scholarly journals Extraction and Mass Spectrometric Characterization of Terpenes Recovered from Olive Leaves Using a New Adsorbent-Assisted Supercritical CO2 Process

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1301
Author(s):  
Zully J. Suárez Montenegro ◽  
Gerardo Álvarez-Rivera ◽  
Jose A. Mendiola ◽  
Elena Ibáñez ◽  
Alejandro Cifuentes
Keyword(s):  
Aluminum Oxide ◽  
Silica Gel ◽  
Supercritical Co2 ◽  
Olive Leaves ◽  
Fractionation Process ◽  
Selective Enrichment ◽  
Adsorption Desorption ◽  
First Time ◽  
By Products

This work reports the use of GC-QTOF-MS to obtain a deep characterization of terpenoid compounds recovered from olive leaves, which is one of the largest by-products generated by the olive oil industry. This work includes an innovative supercritical CO2 fractionation process based on the online coupling of supercritical fluid extraction (SFE) and dynamic adsorption/desorption for the selective enrichment of terpenoids in the different olive leaves extracts. The selectivity of different commercial adsorbents such as silica gel, zeolite, and aluminum oxide was evaluated toward the different terpene families present in olive leaves. Operating at 30 MPa and 60 °C, an adsorbent-assisted fractionation was carried out every 20 min for a total time of 120 min. For the first time, GC-QTOF-MS allowed the identification of 40 terpenoids in olive leaves. The GC-QTOF-MS results indicate that silica gel is a suitable adsorbent to partially retain polyunsaturated C10 and C15 terpenes. In addition, aluminum oxide increases C20 recoveries, whereas crystalline zeolites favor C30 terpenes recoveries. The different healthy properties that have been described for terpenoids makes the current SFE-GC-QTOF-MS process especially interesting and suitable for their revalorization.

scholarly journals Electrospun Membranes Based on Polycaprolactone, Nano-Hydroxyapatite and Metronidazole

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 931
Author(s):  
Ioana-Codruţa Mirică ◽  
Gabriel Furtos ◽  
Ondine Lucaciu ◽  
Petru Pascuta ◽  
Mihaela Vlassa ◽  
...  
Keyword(s):  
Fiber Diameter ◽  
Maximum Load ◽  
Guided Bone Regeneration ◽  
Attenuated Total Reflectance ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Total Reflectance ◽  
X Ray ◽  
Electrospun Membranes

The aim of this research was to develop new electrospun membranes (EMs) based on polycaprolactone (PCL) with or without metronidazole (MET)/nano-hydroxyapatite (nHAP) content. New nHAP with a mean diameter of 34 nm in length was synthesized. X-ray diffraction (XRD) and attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR) were used for structural characterization of precursors and EMs. The highest mechanical properties (the force at maximum load, Young’s modulus and tensile strength) were found for the PCL membranes, and these properties decreased for the other samples in the following order: 95% PCL + 5% nHAP > 80% PCL + 20% MET > 75% PCL + 5% nHAP + 20% MET. The stiffness increased with the addition of 5 wt.% nHAP. The SEM images of EMs showed randomly oriented bead-free fibers that generated a porous structure with interconnected macropores. The fiber diameter showed values between 2 and 16 µm. The fiber diameter increased with the addition of nHAP filler and decreased when MET was added. New EMs with nHAP and MET could be promising materials for guided bone regeneration or tissue engineering.

Design and Characterization of Novel Dirhodium Coordination Polymers - The Impact of Ligand Size on Selectivity in Asymmetric Cyclopropanation

2021 ◽  
Author(s):  
Zhenzhong Li ◽  
Lorenz Roesler ◽  
Till Wissel ◽  
Hergen Breitzke ◽  
Kathrin Hofmann ◽  
...  
Keyword(s):  
Coordination Polymers ◽  
Ligand Exchange ◽  
Dicarboxylic Acids ◽  
Sem Images ◽  
Asymmetric Cyclopropanation ◽  
The Impact

Three chiral dirhodium coordination polymers Rh2-Ln (n=1-3) have been synthesized via ligand exchange between dirhodium trifluoroacetate Rh2(TFA)4 and differently sized chiral dicarboxylic acids derived from L-tert-leucine. SEM images indicate that...

scholarly journals Acoustic Characterization of Some Steel Industry Waste Materials

2021 ◽  
Vol 11 (13) ◽  
pp. 5924
Author(s):  
Elisa Levi ◽  
Simona Sgarbi ◽  
Edoardo Alessio Piana
Keyword(s):  
Thermal Characteristic ◽  
Environmental Benefits ◽  
Acoustic Properties ◽  
Physical Parameters ◽  
Industry Waste ◽  
Acoustic Characterization ◽  
Minimization Procedure ◽  
The Difference ◽  
By Products

From a circular economy perspective, the acoustic characterization of steelwork by-products is a topic worth investigating, especially because little or no literature can be found on this subject. The possibility to reuse and add value to a large amount of this kind of waste material can lead to significant economic and environmental benefits. Once properly analyzed and optimized, these by-products can become a valuable alternative to conventional materials for noise control applications. The main acoustic properties of these materials can be investigated by means of a four-microphone impedance tube. Through an inverse technique, it is then possible to derive some non-acoustic properties of interest, useful to physically characterize the structure of the materials. The inverse method adopted in this paper is founded on the Johnson–Champoux–Allard model and uses a standard minimization procedure based on the difference between the sound absorption coefficients obtained experimentally and predicted by the Johnson–Champoux–Allard model. The results obtained are consistent with other literature data for similar materials. The knowledge of the physical parameters retrieved applying this technique (porosity, airflow resistivity, tortuosity, viscous and thermal characteristic length) is fundamental for the acoustic optimization of the porous materials in the case of future applications.

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