Synthesis of Modified Starch/Polyvinyl Alcohol Composite for Treating Textile Wastewater

In this work, we demonstrated a strategy to design a modified starch/polyvinyl alcohol composite (CCSP), which was employed as a highly efficient and economical fixed-bed adsorbent for treating textile wastewater. Characterization revealed that most of the CCSP was shaped with the morphology of sphericity, and had some water swelling properties. The crystallinity of the CCSP was lower than that of native starch and polyvinyl alcohol, and its average particle size gradually increased with the dosage increase of cationic starch in the preparation. Adsorption experiments showed that the adsorption capacities of CCSP were more than 605 and 539 mg/g for Reactive Black 5 and Reactive Orange 131, respectively, which were over 10 times larger than that of commercial activated carbon (AC). The mixture adsorbent composed of CCSP and AC could remove starch, polyvinyl alcohol, and dyes from textile wastewater completely and simultaneously combined with the fixed-bed technique, and its adsorption capacity was conducted as a function of the bed height and flow rate. Most importantly, the disabled mixture adsorbent could be converted into regenerated AC through a chemical activation process, thereby avoiding the production of solid waste. This study will provide a new efficient green sustainable method for treating textile wastewater.

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Changes in Particle Size Distributions on a Fixed Bed of Granular Activated Carbon

Water Science & Technology ◽

10.2166/wst.1986.0004 ◽

1986 ◽

Vol 18 (1) ◽

pp. 31-42 ◽

Cited By ~ 6

Author(s):

E. A. Shpirt ◽

K. T. Alben

Keyword(s):

New York ◽

Particle Size ◽

Activated Carbon ◽

Average Particle Size ◽

Fixed Bed ◽

Treatment Plant ◽

Granular Activated Carbon ◽

Water Treatment Plant ◽

Average Diameter ◽

Average Particle

The particle size distribution at different bed depths of a fixed bed of granular activated carbon (GAC) has been monitored during 50 weeks of a pilot column run at the Waterford, New York potable water treatment plant. Initial backwashing resulted in significant stratification of GAC in the column: larger particles (average diameter 1.18 mm) settled in the bottom of the column (105 cm), and smaller particles (average diameter 0.97 mm) were concentrated near the top (24 cm), compared to samples of unstratified virgin Calgon F400 (average diameter 1.09 mm). During column loading and initial backwashing, more fines were created than were present in the virgin GAC (average 6.5% of GAC fines in the > 40 mesh fraction, compared to only 0.3% in the > 40 mesh fraction for virgin Calgon F400). After 50 weeks of service there was an overall trend toward a smaller average particle size (0.9 mm) with development of a more regular pattern of bed stratification (1.08 mm at the bottom and 0.75 mm at the top). These changes are attributed to breaking of large particles (12-20 mesh) and creation of intermediate size particles (20-30 and 30-40 mesh).

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Synthesis of Gamma-Alumina Nanopowders Using Waste Metal Aluminum and Stability Surfactants

International Journal of Nanoscience ◽

10.1142/s0219581x19500145 ◽

2019 ◽

Vol 19 (02) ◽

pp. 1950014

Author(s):

Sabereh Nazari ◽

Sadegh Nazari ◽

Fariba Mansourizadeh ◽

Gholamreza Karimi

Keyword(s):

Particle Size ◽

Polyethylene Glycol ◽

Polyvinyl Alcohol ◽

Specific Surface ◽

Pore Volume ◽

Average Particle Size ◽

Average Crystallite Size ◽

Average Particle ◽

Gamma Alumina ◽

Metal Aluminum

In this study, high purity gamma-alumina nanopowders with crystalline structures have been prepared via a sol–gel process by waste metal aluminum, HCl, NaOH, Polyethylene glycol (PEG) and polyvinyl alcohol (PVA). Polyethylene glycol and polyvinyl alcohol have been used as stabilizing agents. The characterization of the samples has been performed utilizing XRD, FTIR, SEM, N2 adsorption/desorption techniques. Prepared samples of gamma-alumina at 800∘C with PEG has an average crystallite size of 2.58[Formula: see text]nm, average particle size of 21[Formula: see text]nm, specific surface area (SSA) of 65.55[Formula: see text]m2/g, and pore volume of [Formula: see text]0.06[Formula: see text]cm3/g. The average crystallite size of 3.07[Formula: see text]nm, average particle size of 31[Formula: see text]nm, specific surface area of 131.25[Formula: see text]m2/g, and pore volume of [Formula: see text]0.14[Formula: see text]cm3/g, were obtained using PVA surfactant.

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Activated Carbon Produced by Pyrolysis of Waste Wood and Straw for Potential Wastewater Adsorption

Materials ◽

10.3390/ma13092047 ◽

2020 ◽

Vol 13 (9) ◽

pp. 2047 ◽

Cited By ~ 7

Author(s):

Katarzyna Januszewicz ◽

Paweł Kazimierski ◽

Maciej Klein ◽

Dariusz Kardaś ◽

Justyna Łuczak

Keyword(s):

Activated Carbon ◽

Surface Area ◽

Activated Carbons ◽

Chemical Activation ◽

Fixed Bed ◽

Fixed Bed Reactor ◽

Physical Activation ◽

Activation Process ◽

Waste Wood ◽

Carbon Production

Pyrolysis of straw pellets and wood strips was performed in a fixed bed reactor. The chars, solid products of thermal degradation, were used as potential materials for activated carbon production. Chemical and physical activation processes were used to compare properties of the products. The chemical activation agent KOH was chosen and the physical activation was conducted with steam and carbon dioxide as oxidising gases. The effect of the activation process on the surface area, pore volume, structure and composition of the biochar was examined. The samples with the highest surface area (1349.6 and 1194.4 m2/g for straw and wood activated carbons, respectively) were obtained when the chemical activation with KOH solution was applied. The sample with the highest surface area was used as an adsorbent for model wastewater contamination removal.

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Magnetic Porous Controlled Fe3O4–Chitosan Nanostructure: An Ecofriendly Adsorbent for Efficient Removal of Azo Dyes

Nanomaterials ◽

10.3390/nano10061194 ◽

2020 ◽

Vol 10 (6) ◽

pp. 1194 ◽

Cited By ~ 1

Author(s):

Tiago M. Freire ◽

Lillian M. U. D. Fechine ◽

Danilo C. Queiroz ◽

Rafael M. Freire ◽

Juliano C. Denardin ◽

...

Keyword(s):

Azo Dyes ◽

Average Particle Size ◽

Molecular Size ◽

Nitrogen Adsorption ◽

Average Particle ◽

Precipitation Reaction ◽

Reactive Black 5 ◽

Anionic Dyes ◽

Adsorption Mechanisms ◽

Surface Modified

In this work, chitosan/magnetite nanoparticles (ChM) were quickly synthesized according to our previous report based on co-precipitation reaction under ultrasound (US) irradiation. Besides ChM was in-depth structurally characterized, showing a crystalline phase corresponding to magnetite and presenting a spheric morphology, a “nanorod”-type morphology was also obtained after increasing reaction time for eight minutes. Successfully, both morphologies presented a nanoscale range with an average particle size of approximately 5–30 nm, providing a superparamagnetic behavior with saturation magnetization ranging from 44 to 57 emu·g−1. As ChM nanocomposites have shown great versatility considering their properties, we proposed a comparative study using three different amine-based nanoparticles, non-surface-modified and surface-modified, for removal of azo dyes from aqueous solutions. From nitrogen adsorption–desorption isotherm results, the surface-modified ChMs increased the specific surface area and pore size. Additionally, the adsorption of anionic azo dyes (reactive black 5 (RB5) and methyl orange (MO)) on nanocomposites surface was pH-dependent, where surface-modified samples presented a better response under pH 4 and non-modified one under pH 8. Indeed, adsorption capacity results also showed different adsorption mechanisms, molecular size effect and electrostatic attraction, for unmodified and modified ChMs, respectively. Herein, considering all results and nanocomposite-type structure, ChM nanoparticles seem to be a suitable potential alternative for conventional anionic dyes adsorbents, as well as both primary materials source, chitosan and magnetite, are costless and easily supplied.

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Evaluation of Formulation Parameters for Development of Aceclofenac Nanosuspension Using Doe Statistical Tool

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.v6i4.8900 ◽

2016 ◽

Vol 6 (4) ◽

Author(s):

Sharma Shivkant ◽

Issarani Roshan ◽

Nagori Prakash

Keyword(s):

Particle Size ◽

Polyvinyl Alcohol ◽

Optimization Technique ◽

Average Particle Size ◽

Experimental Methodology ◽

Average Particle ◽

Saturation Solubility ◽

Formulation Parameters ◽

Dissolution Efficiency ◽

Formulation Variables

InThe objective of present study was to identify and evaluate formulation variables affecting characteristics of nanosuspension formulations. Full factorial design experimental methodology was used for development of aceclofenac nanosuspension. Formulation factors evaluated were drug to polymer (Polyvinyl alcohol) ratio, amount of surfactant (Sodium dodecyl sulphate) relative to drug and solvent employed for carrying the drug. Total 18 formulations were prepared and their saturation solubility in distilled water and z average particle size were regarded as responses in this study. The response surface methodology utilizing polynomial equation was used to quantify the effect of each formulation variables. All three variables exerted significant effect on particle size and saturation solubility. Optimized nanosuspensions were obtained using numerical optimization technique by the desirability approach. The optimum formulation parameters were found to be 400% w/w of drug to polymer ratio and 7.5% w/w of amount of SDS for both solvents. The best optimized formulation obtained from ethanol showed significantly improved saturation solubility 255.39 µg/ml, particle size 477.7 nm and better dissolution efficiency (DE05) 59.77%. The absence of interactions between drug and polymers was confirmed by Fourier transform infrared (FTIR) spectroscopy. The results demonstrated that polyvinyl alcohol was successfully employed for the development of nanosuspension of aceclofenac with higher dissolution efficiency leading to better oral bioavailability.

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Preparation of Silver Nanoparticles in a Plasma-Liquid System in the Presence of PVA: Antimicrobial, Catalytic, and Sensing Properties

Journal of Chemistry ◽

10.1155/2020/5380950 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Margarita I. Skiba ◽

Victoria I. Vorobyova ◽

Iryna V. Kosogina

Keyword(s):

Polyvinyl Alcohol ◽

Catalytic Reduction ◽

Average Particle Size ◽

Liquid System ◽

Localized Surface Plasmon ◽

Average Particle ◽

Technological Parameters ◽

Short Term ◽

Ag Nps ◽

Sem Images

The preparation of stabilized silver nanodispersions under the action of short-term plasma discharge using a polyvinyl alcohol stabilizer (polyvinyl alcohol (PVA)) was investigated. The influence of the basic technological parameters such as initial Ag+ concentration, PVA concentration, and process duration on the formation of nanoparticles and their characteristics (size and stability) were determined. The UV-Vis spectra showed the localized surface plasmon resonance at wavelengths of 400–420 nm. The SEM images showed that the shape of Ag NPs is spherical with an average particle size up to 30 nm. Ag NPs were used as a catalyst for the reduction of 4-nitrophenol (4-NP). The effect of the concentration of PNP and catalyst dosage on the value of apparent rate constant (kapp) for catalytic reduction of 4-NP in the presence of Ag NPs was investigated by means of UV-Vis spectrophotometry. The antimicrobial activity of Ag nanoparticles was investigated against yeast and Escherichia coli. The colorimetric sensor studies of plasma synthesized Ag NPs showed selective sensing of the potentially hazardous Hg2+ ion in water.

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Electrospun synthesis of silver/poly (vinyl alcohol) nano-fibers: investigation antibacterial activity and flame retardant property

10.21203/rs.3.rs-248410/v1 ◽

2021 ◽

Author(s):

Sara Azarakhsh ◽

Hamed Bahiraei ◽

Gholamhosain Haidari ◽

Davood Ghanbar

Keyword(s):

Polyvinyl Alcohol ◽

Flame Retardant ◽

Ag Nanoparticles ◽

Average Particle Size ◽

Water Soluble ◽

Poly Vinyl Alcohol ◽

Average Particle ◽

Sem Images ◽

Water Soluble Polymer ◽

Nano Fiber

Abstract Polyvinyl alcohol (PVA) and Ag nanoparticles-embedded polyvinyl alcohol (Ag/PVA) nano-fibers have been synthesized successfully via the electro-spinning technique at room temperature. XRD patterns confirmed the presence of Ag nanoparticles in the electro-spinning PVA nano-fibers. FE-SEM images displayed that silver nanoparticles with an average particle size of 32 nm are uniformly dispersed in PVA nano-fibers. Also, the average diameter of Ag/PVA nano-fibers was estimated to be 142 nm. The EDX analysis of Ag/PVA nano-fiber determined the aggregation of Ag nanoparticles in the range of polymer nano-fibers. The antibacterial property of Ag/PVA nano-fiber for inhibition of Escherichia coli (E-coli) growth was approved. Since polyvinyl alcohol is a biocompatible and water-soluble polymer, it can be considered as unique candidate for the preparation of wound dressing nano-fibers. It is also found that the nontoxic nanostructures can appropriately enhance both flame retardant and thermal stability properties of the Ag/PVA matrix. These results show that the Ag/PVA nano-fibers may find practical applications as self-reinforced medical devices and tissue-engineering scaffolds.

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Characterization of Bottom Ash Waste Adsorbent from Palm Oil Plant Boiler Burning Process to Adsorb Carbon Dioxide in a Fixed Bed Column

Indonesian Journal of Chemistry ◽

10.22146/ijc.66509 ◽

2021 ◽

Vol 21 (6) ◽

pp. 1454

Author(s):

Novi Sylvia ◽

Fitriani Fitriani ◽

Rozanna Dewi ◽

Rizka Mulyawan ◽

Abrar Muslim ◽

...

Keyword(s):

Palm Oil ◽

Contact Time ◽

Co2 Adsorption ◽

Average Particle Size ◽

Fixed Bed ◽

Bottom Ash ◽

Average Particle ◽

Fixed Bed Column ◽

Bed Height ◽

Ft Ir

Palm oil bottom ash utilization from mill boilers as CO2 adsorbent has been in use for few years. This study aims to examine adsorbent characteristics and capabilities of bottom ash produced from boiler combustion in palm oil industry for CO2 adsorption before and after utilization, such as compound functional group using the Fourier Transform Infra-Red (FT-IR) spectrophotometer, adsorbent morphology through Scanning Electron Microscopy (SEM), and compound amount using Energy Dispersive X-Ray Spectroscopy (EDX). The CO2 adsorption was carried out in fixed-bed column. Process variables consist of volumetric flow rate, contact time and bed height. Results showed that SiO2 compounds in the heterogeneous form with average particle size of 1073 nm, as supported by FT-IR spectrum finding indicating SiO2 signal at wavelength of 958–954 cm–1. Additionally, EDX analysis showed Silica and Oxygen content of 11.88% and 36.90%, resulting 70% CO2 adsorption capacity of 0.350 mg/g at discharge of 5 L/min, contact time of 40 min, and bed height of 12 cm. Langmuir isotherm model was obtained with R2 of 0.998, qm of 1.588, and kL of 0.144. Meanwhile, the kinetic model followed a simple first-order prototypical with R2 of 0.952, C02 of 0.260, and k1 of 0.006.

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Optimization of Manufacturing Conditions for Activated Carbon from Coffee (Coffea Arabica L.) Bean Waste by Chemical Activation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.658.113 ◽

2010 ◽

Vol 658 ◽

pp. 113-116 ◽

Cited By ~ 2

Author(s):

Chiravoot Pechyen ◽

Duangdao Aht-Ong ◽

Viboon Sricharoenchaikul ◽

Duangduen Atong

Keyword(s):

Activated Carbon ◽

Surface Area ◽

Coffea Arabica ◽

Activated Carbons ◽

Chemical Activation ◽

Fixed Bed ◽

Fixed Bed Reactor ◽

Activation Process ◽

Type I ◽

Coffee Bean

Pyrolysis is one form of energy recovery process which has the potential to generate oil, gas and char products. The char becomes an attractive by-product, with applications including production of activated carbons that is useful as a sorbent for wastewater treatment and air pollution control. In this work, activated carbon was prepared from Coffee (Coffea Arabica L.) bean waste collected from local coffee houses. Char from pyrolysis of coffee bean waste at 900 °C contained high fixed carbon and low volatile content that was favorable for subsequent activation process. The char was activated via chemical treatment with sodium hydroxide (NaOH) at five different NaOH : char ratios (1:1, 2:1, 3:1, 4:1 and 5:1) and heat treated at 400°C for 15 minutes using a fixed bed reactor under nitrogen atmosphere with a flow rate of 100 mL/min. Result shows that NaOH works effectively as dehydration reagent around 400°C. Under the experimental conditions investigated, impregnation ratio of 1.0 was found to be suitable for producing high-surface area activated carbon. The surface area and total pore volume of activated carbons, which were determined by application of the Brunauer–Emmett–Teller (BET) and t-plot methods, were achieved as high as 802 m2/g and 0.80 cm3/g, respectively. The chemically activated carbons were found to be mainly type I carbons and had high adsorption property (Methylene blue adsorption = 284 mg/g and Iodine number = 1070 mg/g).

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Mixed Surfactant Template Method for Preparation of Nanometer Selenium

E-Journal of Chemistry ◽

10.1155/2009/109608 ◽

2009 ◽

Vol 6 (s1) ◽

pp. S304-S310 ◽

Cited By ~ 2

Author(s):

Zhi-Lin Li ◽

Peng-Min Hua

Keyword(s):

Sodium Dodecyl Sulfate ◽

Polyvinyl Alcohol ◽

Mass Fraction ◽

Room Temperature ◽

Average Particle Size ◽

Sodium Dodecyl ◽

Soft Template ◽

Average Particle ◽

Mixed Surfactant ◽

Dodecyl Sulfate

Selenium nanoparticles have been synthesized in an aqueous solution by using sodium dodecyl sulfate and polyvinyl alcohol as a soft template. The factors on synthesis, such as reaction time, concentration of reactants and ultrasonic irradiation were studied. The uniform stable selenium nanospheres were obstained in the conditions of 1.0 (mass fraction) sodium dodecyl sulfate, 1.0 (mass fraction) polyvinyl alcohol, n(Vc):n(H2SeO3)=7:1 and 7 minutes after the initiation of the reaction at room temperature. The average particle size of selenium is about 30 nm. The product was characterized by UV and TEM. Finally the applications of the red element nanometer selenium in anti-older cosmetics are presented.

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