Preparation of PCL/Clay and PVA/Clay Electrospun Fibers for Cadmium (Cd+2), Chromium (Cr+3), Copper (Cu+2) and Lead (Pb+2) Removal from Water

Wang

J Polym Sci B Polym Phys

et al. 2019

Superhydrophobic polycaprolactone (PCL) membranes with hierarchical structure were fabricated via alternate electrospinning/electrospraying techniques. Electrospun PCL/methyl silicone oil (PCL/MSO) nanofibers were employed as substrate. PCL/MSO‐PCL microspheres (PCL/MSO‐PCLMS) hierarchical membrane was prepared via electrosprayed PCLMS as an additional layer on the substrate. Field emission scanning electron microscopy images showed the formation of hierarchical PCL/MSO‐PCLMS membranes. Compared to pure PCL fibers substrate (120 ± 1.3°), the water contact angle (WCA) of MSO‐modified PCL membrane was 142 ± 0.7°. The most interesting observation was that the WCA of PCLMS without any modification could be achieved to 146 ± 2.8°. On this basis, PCL/MSO‐PCLMS hierarchical membrane possessed superhydrophobic surface with 150 ± 0.6° of WCA. The excellent surface roughness and air‐pocket capacity of hierarchical membranes would make the membranes more hydrophobic. The maximum oil (n‐hexane) adsorption capacity of PCL/MSO‐PCLMS membrane was 32.53 g g−1. Oil–water separation efficiencies of the superhydrophobic membranes were all higher than 99.93% after 10 cycles. The hierarchically structured PCL superhydrophobic membranes indicate the potential applications of environmentally friendly biopolymers as separation membranes. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 421–430

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Preparation of hierarchically structured PCL superhydrophobic membrane via alternate electrospinning/electrospraying techniques

Wang

J Polym Sci B Polym Phys

et al. 2019

“…Hota et al studied sorption of Cd +2 ions by electrospun PA6 and PCL membrane inclusion of ceramic boehmite NPs and found that sorption capacity of polymer/boehmite is much higher (0.2 mg/L) than polymer NFs alone (0.002 mg/L) [94]. Another study demonstrated for electrospun PCL/clay and PVA/clay that NFs are suitable for use in heavy metal removal of cadmium (Cd +2 ), chromium (Cr +3 ), copper (Cu +2 ) and lead (Pb +2 ) from water due to the high surface activity [141]. Further studies showed that the adsorptive property of fly ash and photocatalytic property of TiO 2 can introduce different functionalities on PU mat for water purification.…”

Section: Applications Of Ceramic Electrospun Matsmentioning

confidence: 99%

Electrospun Ceramic Nanofiber Mats Today: Synthesis, Properties, and Applications

2017

Ceramic nanofibers (NFs) have recently been developed for advanced applications due to their unique properties. In this article, we review developments in electrospun ceramic NFs with regard to their fabrication process, properties, and applications. We find that surface activity of electrospun ceramic NFs is improved by post pyrolysis, hydrothermal, and carbothermal processes. Also, when combined with another surface modification methods, electrospun ceramic NFs result in the advancement of properties and widening of the application domains. With the decrease in diameter and length of a fiber, many properties of fibrous materials are modified; characteristics of such ceramic NFs are different from their wide and long (bulk) counterparts. In this article, electrospun ceramic NFs are reviewed with an emphasis on their applications as catalysts, membranes, sensors, biomaterials, fuel cells, batteries, supercapacitors, energy harvesting systems, electric and magnetic parts, conductive wires, and wearable electronic textiles. Furthermore, properties of ceramic nanofibers, which enable the above applications, and techniques to characterize them are briefly outlined.

Bull. Chem. React. Eng. Catal.

“…The removal percentage of all three heavy metal ions increased with the absorbent concentration, gradually reaching a plateau value. A higher amount of chitosan-loaded bentonite adsorbent means more adsorption sites available for the heavy metal ions, therefore the heavy metal ion removal is improved [28]. (Figure 16).…”

Section: Adsorption Performance Of Chitosanloaded Bentonite Claymentioning

confidence: 99%

“…The percentages of Cu(II), Cr(VI), and Pb(II) adsorption increased with the chitosan loading. An optimal chitosan loading should enhance the adsorption capacity of the clay, without clogging its adsorption channels (which is detrimental for the adsorption of heavy metal ions) [6,28].…”

Section: Adsorption Performance Of Chitosanloaded Bentonite Claymentioning

confidence: 99%

Effects of Bentonite Activation Methods on Chitosan Loading Capacity

Fan

et al. 2017

The adsorption capacity of bentonite clay for heavy metal removal from wastewater can be significantly enhanced by a high loading of chitosan on the surface. In order to enhance the chitosan loading, we tested activating bentonite clay by three methods prior to chitosan loading: sulfuric acid, calcination, and microwave treatments. Meanwhile, several parameters during chitosan loading, namely the initial chitosan concentration, stirring speed, reaction time, temperature, and pH value were investigated. Our results indicate that chitosan is attached to bentonite clay through intercalation and surface adsorption according to X-ray Diffraction (XRD), Scanning Eelectron Microscopy (SEM), and Fourier Transform Infrared Spectroscopy (FTIR) analyses. The maximum chitosan loading on 200-mesh raw bentonite clay (126.30 mg/L) was achieved under the following conditions: the initial chitosan concentration of 1000 mg/L, the stirring speed of 200 rpm, pH of 4.9, 60 min of reaction time, and temperature of 30 °C. The chitosan loading was further increased to 256.30, 233.70, and 208.83 mg/g, when using bentonite clay activated through 6 min of microwave irradiation (800 W), 10 % sulfuric acid treatment, and calcinations at 600 °C, respectively. When the chitosan loading was increased from 34.76 to 233.7 mg/g, the removal percentages of Cu(II), Cr(VI), and Pb(II) were improved, respectively from 78.90 to 95.5 %, from 82.22 to 98.74 %, from 60.09 to 86.18 %.