Waste Jute Fabric as a Biosorbent for Heavy Metal Ions from Aqueous Solution

A. Ivanovska,B. Dojcinovic,S. Maletic,L. Pavun,K. Asanovic,M. Kostic 한국섬유공학회 2020 Fibers and polymers Vol.21 No.9

The influence of the chemical composition on the biosorption potential of waste jute fabric for Ni2+, Cu2+, and Zn2+was investigated. The raw jute fabric was treated with sodium hydroxide or sodium chlorite to selectively removehemicelluloses and lignin, respectively. All jute fabrics were characterized by determination of their chemical composition aswell as functional group content. The effects of solution pH, contact time, and initial metal ion concentration on thebiosorption from monometallic and polymetallic solution by jute fabrics were investigated. The maximum biosorptioncapacity for all heavy metal ions was observed at pH 5.5. Concerning the contact time, the raw jute fabric shows more than72 % of the total uptake capacity of Ni2+, Cu2+, and Zn2+ within 1 h, while the jute fabrics with lower hemicelluloses andlignin content show between 72-85 % of the total uptake capacity within 3 h. Increased initial metal ion concentration from10 to 20 mg/l in monometallic solution caused an increase in the total uptake capacity of jute fabrics with lowerhemicelluloses and lignin content for 47-69 % (Ni2+), 42-63 % (Cu2+), and 22-37 % (Zn2+). The biosorption capacity of alkalitreated jute fabrics was affected by the changes in the total amount of carboxyl and aldehyde groups that accompany thehemicelluloses removal. In the case of the oxidative treatment, the biosorption capacity was affected by the lignin content aswell as the amount of introduced carboxyl groups. The best biosorption performance possesses jute fabric with 63.2 % lowerlignin content as well as 81.1 % higher amount of carboxyl groups; biosorption capacity toward Ni2+, Cu2+, and Zn2+ inmonometallic solution is about 2.4; 2.2 and 3.5 times higher compared to the raw jute fabric, respectively. All jute fabricsexhibited the same affinity order (which is independent on the initial metal ion concentrations) toward heavy metal ions: Ni2+> Cu2+ > Zn2+ in the case of competitive biosorption. An increase in the initial metal ion concentration for two times in thepolymetallic solution caused about a 35-59 % increase in the total uptake capacity of Ni2+, while the total uptake capacities ofCu2+ and Zn2+ increased for 19-38 % and 18-65 %, respectively.

Alkali Treated Jute Fabrics Suitable for the Production of Inexpensive Technical Textiles

Aleksandra Ivanovska,Koviljka Asanović,Maja Jankoska,Sanja Pavlović,Goran Poparić,Mirjana Kostić 한국섬유공학회 2022 Fibers and polymers Vol.23 No.8

This work aimed to obtain jute fabrics suitable for the production of inexpensive technical textiles by using simplealkali treatments. The influences of alkali concentration (1-17.5 % NaOH) and treatment duration (5-30 min) on the fabrics’compression properties, abrasion resistance, and sound absorption coefficient were studied in detail. With increasing thetreatment severity, the fabric compressibility decreases by 19.6-33.9 % due to increased fabric compactness. In parallel, thefiber crystallinity index and hemicellulose content decrease, while the fibers’ interfibrillar regions become less dense and lessrigid contributing to 19.0-27.0 % better recoverability after compression. The mercerized fabrics possessed a notably lowermass loss (4.1-5.9 %) after 750 abrasion cycles compared to the other investigated fabrics (18.9-30.9 %), which could beascribed to the higher friction forces existing between the yarns within the mercerized fabrics and between the fibers withinthe yarns, as well as higher elongation at maximum force. In the case of the fabrics treated for 5 or 15 min with differentNaOH concentrations, their mass losses during abrasion decrease with increasing the elementary fiber liberation, while thesound absorption coefficients increase with increasing the fabric compactness. Mercerized fabrics are capable of absorbingabout 28 % to 2.7 times (at 990 Hz) and 2.0 to 2.4 times (at 4090 Hz) higher mechanical sound energy compared to theuntreated fabric. The jute fabric mercerized during 30 min could be used for the production of carpet backings, while thosemercerized during 5 min is the most suitable for the production of sound-absorbing materials.

Revalorization of Cotton and Cotton/Elastane Knitted Fabric Waste

Aleksandra Ivanovska,Jelena Lađarević,Koviljka Asanović,Leposava Pavun,Mirjana Kostić,Biljana Mangovska 한국섬유공학회 2023 Fibers and polymers Vol.24 No.2

The present paper demonstrates a simple way for revalorization of differently softened cotton and cotton/elastane knittedfabric waste collected from the textile industry. Such waste was used as an adsorbent for Congo Red (CR) dye, whereby upto 96% removal efficiency was reached. The CR adsorption process onto cationic and silicone softened fabrics is in conformitywith Langmuir (with maximum adsorption capacity of 12.533 mg/g) and Freundlich isotherms, respectively. Differentadsorption of CR onto cationic and silicone softened fabrics is ascribed to the different softeners’ fixation to them, whilethe adsorption of CR operates in the same manner, via hydrophobic interactions. The adsorption kinetic data follow thepseudo-second-order model, while the equilibrium was reached after 90 min. Additionally, this study proposed a new circulareconomy solution for the disposal of fabric waste with adsorbed CR generating additional revenues. The volume electricalresistivity measurements confirmed that the knitted fabric wastes with adsorbed CR have 169–737 times lower resistivities(0.008–0.037 GΩ·cm) than before the adsorption. The inversely proportional correlation between fabrics’ adsorptionefficiencies and their volume electrical resistivities after CR adsorption was found. Such knitted fabric waste with adsorbedCR could be defined as dissipative materials and could be used for providing antistatic protection.

Information as An Object of Legal Regulation in Ukraine

Iasechko, Svitlana,Ivanovska, Alla,Gudz, Tetyana,Marchuk, Mykola,Venglinskyi, Oleksandr,Tokar, Alla International Journal of Computer ScienceNetwork S 2021 International journal of computer science and netw Vol.21 No.5

The article deals with the problematic issues of defining information as an object of private relations. Definitions that they are intangible and non-consumable by nature, are inextricably linked to a specific material carrier are/or secured by the subject that transmits them, messages, and information that have quantitative and qualitative characteristics, and are capable of having a freight or another value, and in case of its illegal usage causing damage and moral harm.

Multipurpose Nonwoven Viscose/Polypropylene Fabrics: Effect of Fabric Characteristics and Humidity Conditions on the Volume Electrical Resistivity and Dielectric Loss Tangent

Koviljka A. Asanovic,Dragana D. Cerovic,Mirjana M. Kostic,Tatjana V. Mihailovic,Aleksandra M. Ivanovska 한국섬유공학회 2020 Fibers and polymers Vol.21 No.10

In this work, the volume electrical resistivity and dielectric loss tangent of viscose/polypropylene multipurposenonwoven fabrics were examined. According to the obtained results, the changes in the volume electrical resistivity dependon the applied chemical bonding agent, viscose fiber content, moisture content, fabric thickness, fabric weight, and relativeair humidity. Based on the volume electrical resistivity hysteresis, the portion of sorbed moisture retained in the material afterdesorption, as well as the portion of moisture removed from the material during desorption, were determined. Furthermore,the dielectric loss tangent measured at the frequency range between 30 Hz and 140 kHz, for the samples exposed to differentrelative air humidity (40 % and 80 %) and wet samples, is dependent on the chemical bonding agent, viscose fiber content,moisture content, as well as frequency of the external electric field. The dielectric loss tangent measured at 80 % relative airhumidity showed a peak at about 100 Hz, while for the wet samples, the peak was observed in the frequency range between30 and 140 kHz. In a wet state, the dielectric loss tangent is primarily influenced by the water molecules present in thesample.