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The purpose of this paper is to investigate the influence of some structural characteristics of terry fabrics on the rate of sorption.

Fabrics are produced by changing the weft density and the pile height. An experimental stand for dynamic measurement of water sorption is created. The quantities of water absorbed by the fabric over time are determined. The sorption rates are calculated and discussed.

The dynamics of the sorption process are assessed through the sorption curves presented. The sorption rates for the main sorption stages, as well the average rate for weft and warp direction, are calculated. Results are statistically worked out applying ANOVA. Appropriate conclusions about the influence of the investigated parameters on sorption process are made.

The originality/value of this paper is: determination of the rates of water sorption for the particular time intervals and the average rates for the entire test period; and assessment of the infuence of the loop height and weft density on the sorption rates.

In recent years, oil spill pollution has become one of the main problems of environmental pollution. Recovering oil by means of sorbent materials is a very promising approach and has acquired more attention due to its high cleanup efficiency. Compared to synthetic fibrous sorbents, the use of natural fibers in oil spill cleanups offers several advantages including environmental friendliness, degradable features and cost-effectiveness. Therefore, studies on developing sorbents using natural fibers for oil spill cleanup applications have become a research hotspot.

This paper reviews the work conducted by several researchers in developing oil sorbents from fibers such as cattail, nettle, cotton, milkweed, kapok, populous seed fiber and Metaplexis japonica fiber. Some featured critical parameters influencing the oil sorption capacity of fibrous substrates are discussed. Oil sorption capacity and reusability performance of various fibers are also discussed. Recent developments in oil spill cleanups and test methods for oil sorbents are briefly covered.

The main parameters influencing the oil sorption capacity of sorbents are fiber morphological structure, fiber density (g/cc), wax (%), hollowness (%) and water contact angle. An extensive literature review showed that oil sorption capacity is highest for Metaplexis japonica fiber followed by populous seed fiber, kapok, milkweed, cotton, nettle and cattail fiber. After use, the sorbents can be buried under soil or they can also be burned so that they can be vanished from the surface without causing environmental-related issues.

This review paper aims to summarize research studies conducted related to various natural fibers for oil spill cleanups, fiber structural characteristics influencing oil sorption and recent developments in oil spill cleanups. This work will inspire future researchers with various knowledge backgrounds, particularly, from a sustainability perspective.

In order to understand interactions a_w vs equilibrium moisture content (EMC) in fortified coconut powder, moisture sorption isotherms were constructed under different storage conditions in order to predict the changes in their physical, chemical and microbiological properties that occur during storage and processing, which are unique to each food.

For which the moisture sorption isotherms were determined at three different temperatures (15, 25 and 35 °C), in a range of water activity from 0.1 to 0.90. Nine models, namely, the GAB, BET, Oswin, Smith, Halsey, Henderson, Chung and Pfost, Peleg and Caurie equations, were fitted to the sorption data. Various statistical tests were adopted as criteria to evaluate the fit performance of the models.

Of the models tested, the Peleg model gave the best fit to experimental data (R² = 0.997; R_MSE = 0.276), across the full range of water activities and at different temperatures. Humidity of the monolayer (m_o) was found between 2.54 and 2.34%, a fundamental parameter to define the storage and control conditions, given that it is considered the value at which the product is more stable. The net sorption isosteric heat (Q_st) increased to maximum and then diminished with increased moisture content (X_w); maximum values were obtained in the X_w interval between 0.48 and 2.87% (db), being between 35.72 and 99.26 kJ/mol, where the maximum value indicates coverage of the strongest bond sites and higher adsorbate-adsorbent interaction.

These results provide reliable experimental data on water absorption isotherms of the CP + FAC important to determine optimal processing, storing and packaging conditions.

The most widely recycled plastic in the world is recycled polyethylene terephthalate (rPET). To minimize the environmental related issues associated with synthetic fibers, several researchers have explored the potential use of recycled polyester fibers in developing various technical textile products. This study aims to develop needle-punched nonwoven fabrics from recycled polyester fibers and investigate its suitability in oil spill cleanup process.

According to Box and Behnken factorial design, 15 different needle-punched nonwoven fabrics from recycled polyester fibers were prepared by changing the parameters, namely, needle punch density, needle penetration depth and fabric areal weight. Several featured parameters such as oil sorption, oil retention, oil sorption kinetics, wettability and reusability performance were systematically elucidated.

The maximum oil sorption of recycled nonwoven polyester is found to be 24.85 g/g and 20.58 g/g for crude oil and vegetable oil, respectively. The oil retention is about 93%–96% in case of crude oil, whereas 87%–91% in case of vegetable oil. Recycled polyester nonwoven possesses good hydrophobic–oleophilic properties with static contact angle of 138° against water, whereas 0° against crude oil and vegetable oil. The reusability test results indicate that recycled polyester nonwoven fabric can be used several times because of its reusability features.

There is no detailed study on the oil sorption features of needle-punched nonwoven fabrics developed from recycled polyester fibers. This study is expected to help in developing fabrics for oil spill cleanups.

The purpose of this paper is to investigate the possible application of recycled wool‐based nonwoven material (RWNM) for removal of different dyes that are used in textile dye houses.

The sorption kinetics, the influence of initial dye concentration, pH and temperature are analyzed. Basic, reactive, direct and metal complex dyes are studied.

The sorption properties are highly influenced by the type of the dye owing to differences in their chemical structure and thus, the mechanism of binding to wool. Modification of material with chitosan and hydrogen peroxide improves the sorption capacities and sorption rates but no general trend can be established. Consequently, the sorption behaviour is analyzed separately for each type of the dye.

The results indicate that RWNM can be used as an efficient, low‐cost sorbent for decolorisation of effluents.

The purpose of this paper is to investigate the performance of natural Jordanian zeolite tuff to remove ammonia from aqueous solutions using a laboratory batch method and fixed-bed column apparatus. Equilibrium data were fitted to Langmuir and Freundlich models.

Column experiments were conducted in packed bed column. The used apparatus consisted of a bench-mounted glass column of 2.5 cm inside diameter and 100 cm height (column volume = 490 cm3). The column was packed with a certain amount of zeolite to give the desired bed height. The feeding solution was supplied from a 30 liter plastic container at the beginning of each experiment and fed to the column down-flow through a glass flow meter having a working range of 10-280ml/min.

Ammonium ion exchange by natural Jordanian zeolite data were fitted by Langmuir and Freundlich isotherms. Continuous sorption of ammonium ions by natural Jordanian zeolite tuff has proven to be effective in decreasing concentrations ranging from 15-50 mg NH₄-N/L down to levels below 1 mg/l. Breakthrough time increased by increasing the bed depth as well as decreasing zeolite particle size, solution flow-rate, initial NH₄+ concentration and pH. Sorption of ammonium by the zeolite under the tested conditions gave the sorption capacity of 28 mg NH₄-N/L at 20°C, and 32 mg NH₄-N/L at 30°C.

This research investigates the performance of natural Jordanian zeolite tuff to remove ammonia from aqueous solutions using a laboratory batch method and fixed-bed column apparatus. The equilibrium data of the sorption of Ammonia were plotted by using the Langmuir and Freundlich isotherms, then the experimental data were compared to the predictions of the above equilibrium isotherm models. It is clear that the NH₄+ ion exchange data fitted better with Langmuir isotherm than with Freundlich model and gave an adequate correlation coefficient value.

Nowadays trace organic pollutants represent a major concern in water treatment systems. Activated carbon has been used for most applications aiming at the reduction of these kind of compounds in aqueous effluents, but regeneration needs and high operation costs led to a renewed interest in the search for alternative sorbents. Pine bark is an excedentary raw material from sawmills in Portugal, and therefore a profitable natural resource that has already been successfully tested in the adsorption of organochlorines from contaminated water. This study aims at characterizing the pine bark surface structurally and chemically, to understand the nature of sorption occurring when a trace organic contaminant is present in aqueous effluents. Pentachlorophenol (PCP) was the trace contaminant used in the experiments. Scanning electron microscopy (SEM), mercury porosimetry, Fourier transform infrared spectroscopy (FTIR) and X‐ray photoelectron spectroscopy (XPS) were the techniques used, in addition to classical chemical analysis and solid phase micro extraction (SPME) prior to gas chromatography with mass spectrometry (GC‐MS) for PCP quantification. The pine bark proved to be a material of very low porosity, low specific surface area, strong carbon aromatic content probably relative to polyphenols and lignin composition. Sorption experiments showed a good correlation for the linear adsorption isotherm, as well as the desorption experiments. In the conditions tested, the average PCP removal after 24 h was above 98 per cent. This material proved to be an encouraging sorbent for cheap water remediation solutions.

The paper aims to evaluate drying performance of earth mortar by solar drying for more durability, minimize pathologies in traditional construction and determine the influence of temperature and humidity on the microstructure of earth mortar using static gravimetric method.

A convective solar dryer was used for the pretreatment of building and solid materials for construction.

The humidity influences the mortar sorption – surface water sorption of earth mortar increased with increasing temperature.

The study used a novel method for pretreatment building materials by using solar dryer.

The purpose of this paper is to demonstrate applicability of the pervaporation technique for separation ethanol/water mixtures.

For the purposes of membrane material development for pervaporation zeolite filled and unfilled cellulose acetate membranes were prepared. Zeolite types were 4A, 13X. The effect of incorporation of nano‐sized zeolites prepared in a colloidal form in membranes was also investigated. Equilibrium sorption experiments were carried out. Degrees of swelling were calculated at different liquid feed mixture compositions for separating an azeotrope forming mixture, ethanol/water by pervaporation.

Zeolite 13X filled CA membrane may have the better pervaporation performance than zeolite 4A filled CA membrane. From the sorption tests it is concluded that ethanol/water azeotropy can be achieved by pervaporation.

Application of CA membranes in industrial scale pervaporation units may be feasible for separation of ethanol/water mixtures. Specially ethanol/water azeotropy will be achieved by pervaporation. Using distillation and pervaporation hybrid systems, bioethanol can be produced economically.

The paper illustrates the success of pervaporation techniques in separating ethanol/water mixtures.

The purpose of this study is to investigate how the amount of material used and printing parameters affect the mechanical and water sorption properties of acrylonitrile butadiene styrene printed parts.

The specimens were printed using different printing parameters such as shell number, infill pattern and printing orientation, while accounting for the amount of material used. The mechanical properties of the printed parts were then evaluated using tensile, compression and flexural tests, along with sorption tests.

The results revealed that the maximum tensile stress of 31.41 MPa was obtained when using 100% infill and a horizontal printing orientation. Similarly, the maximum flexural strength and compression of 40.5 MPa and 100.7 MPa, respectively, were obtained with 100% infill. The printing orientation was found to have a greater impact on mechanical behavior compared to the number of shells or infill patterns. Specifically, the horizontal printing orientation resulted in specimens with at least 25% greater strength compared to the vertical printing orientation. Furthermore, the relationship between the amount of material used and strength was evident in the tensile and flexural tests, which showed a close correlation between the two.

This study’s originality lies in its focus on optimizing the amount of material used to achieve the best strength-to-mass ratio and negligible water infiltration. The findings showed that specimens with two shells and a 60% infill density exhibited the best strength-to-mass ratio.