scholarly journals Hydrophilic Surface-Modified PAN Nanofibrous Membranes for Efficient Oil–Water Emulsion Separation

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 197
Author(s):  
Evren Boyraz ◽  
Fatma Yalcinkaya
Keyword(s):  
Membrane Filtration ◽  
Membrane Surface ◽  
Alkaline Treatment ◽  
Oily Wastewater ◽  
Water Contact ◽  
Water Emulsion ◽  
Promising Alternative ◽  
Wastewater Filtration ◽  
Nanofibrous Membranes ◽  
Surface Modified

In order to protect the environment, it is important that oily industrial wastewater is degreased before discharging. Membrane filtration is generally preferred for separation of oily wastewater as it does not require any specialised chemical knowledge, and also for its ease of processing, energy efficiency and low maintenance costs. In the present work, hybrid polyacrylonitrile (PAN) nanofibrous membranes were developed for oily wastewater filtration. Membrane surface modification changed nitrile groups on the surface into carboxylic groups, which improve membrane wettability. Subsequently, TiO2 nanoparticles were grafted onto the modified membranes to increase flux and permeability. Following alkaline treatment (NaOH, KOH) of the hydrolysed PAN nanofibres, membrane water permeability increased two- to eight-fold, while TiO2 grafted membrane permeability increase two- to thirteen-fold, compared to unmodified membranes. TiO2 grafted membranes also displayed amphiphilic properties and a decrease in water contact angle from 78.86° to 0°. Our results indicate that modified PAN nanofibrous membranes represent a promising alternative for oily wastewater filtration.

Preparation and Characterization of Negatively Charged Polysulfone Hollow Fiber Membrane by UV-Photografting Polymerization of AMPS

2010 ◽  
Vol 129-131 ◽  
pp. 295-300
Author(s):  
Xiao Lei Wang ◽  
Jun Fu Wei ◽  
Yan Ming Yang ◽  
Huan Zhang ◽  
Guo Yang Shi
Keyword(s):  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
Morphological Changes ◽  
Membrane Surface ◽  
Streaming Potential ◽  
Attenuated Total Reflection ◽  
Water Contact ◽  
Potential Measurement ◽  
Uf Membranes ◽  
Surface Modified

Polysulfone (PSf) hollow fiber ultrafiltration (UF) membranes were surface-modified by the UV-induced graft polymerization of 2-acrylamido-2-methylpropanesulfonic acid (AMPS). Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and scanning electron microscope (SEM) were employed to characterize the structural and morphological changes on the membrane surface. Water contact angle of PSf-g-AMPS membrane surface decreased to 15.45° when AMPS concentration was 2 wt.%, which was nearly 35° lower than that of the unmodified membrane. The results of streaming potential measurement at different pressures implied the negatively charged characteristic of the PSf-g-AMPS membrane. The flux of PSf-g-AMPS membrane increased about 60% as compared to original PSf membrane and the rejection of heparin sodium for PSf-g-AMPS membrane achieved 78%, which was about 4 times that of PSf membrane at 0.04 MPa.

scholarly journals Detergent and Water Recovery from Laundry Wastewater Using Tilted Panel Membrane Filtration System

Membranes ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 260
Author(s):  
Nafiu Umar Barambu ◽  
Derrick Peter ◽  
Mohd Hizami Mohd Yusoff ◽  
Muhammad Roil Bilad ◽  
Norazanita Shamsuddin ◽  
...  
Keyword(s):  
Environmental Sustainability ◽  
Membrane Fouling ◽  
Membrane Filtration ◽  
Membrane Surface ◽  
Aeration Rate ◽  
Water Recovery ◽  
Wastewater Reclamation ◽  
Permeability Enhancement ◽  
Filtration System ◽  
Wastewater Filtration

Increasing global concern on clean water scarcity and environmental sustainability drive invention in water reclamation technology. Laundry wastewater reclamation via membrane technology faces the challenge of membrane fouling. This paper assesses a tilting-the-filtration-panel filtration system for the treatment of real laundry wastewater filtration aimed for water and detergent reuse. Results showed that the panel tilting significantly improved fouling control and enhanced permeability due to enhanced contact of air bubbles with the membrane surface, which induced continuous detachment of foulant from the membrane surface. The combination of aeration rate and tilting angle resulted in up to 83% permeability enhancement from 109 to 221.4 ± 10.8 (L/m2·h·bar). The system also offers 32% detergent recovery. Overall findings suggest that the system offers an attractive approach for both fouling management and detergent recovery and can potentially be applied under a simple setup in which filtration can be driven by gravity/hydrostatic pressure.

Low-pressure membrane filtration with unconventional coagulation regimes

2005 ◽  
Vol 5 (5) ◽  
pp. 1-8 ◽  
Author(s):  
K.Y. Choi ◽  
B.A. Dempsey
Keyword(s):  
Activated Carbon ◽  
Membrane Filtration ◽  
Membrane Surface ◽  
Cross Flow ◽  
Chemical Cleaning ◽  
Sand Filters ◽  
Charge Neutralization ◽  
Floc Size ◽  
Filtration System ◽  
Pre Treatment

The objective of the research was to evaluate in-line coagulation to improve performance during ultrafiltration (UF). In-line coagulation means use of coagulants without removal of coagulated solids prior to UF. Performance was evaluated by removal of contaminants (water quality) and by resistance to filtration and recovery of flux after hydraulic or chemical cleaning (water production). We hypothesized that coagulation conditions inappropriate for conventional treatment, in particular under-dosing conditions that produce particles that neither settle nor are removed in rapid sand filters, would be effective for in-line coagulation prior to UF. A variety of pre-treatment processes for UF have been investigated including coagulation, powdered activated carbon (PAC) or granular activated carbon (GAC), adsorption on iron oxides or other pre-formed settleable solid phases, or ozonation. Coagulation pre-treatment is often used for removal of fouling substances prior to NF or RO. It has been reported that effective conventional coagulation conditions produced larger particles and this reduced fouling during membrane filtration by reducing adsorption in membrane pores, increasing cake porosity, and increasing transport of foulants away from the membrane surface. However, aggregates produced under sweep floc conditions were more compressible than for charge neutralization conditions, resulting in compaction when the membrane filtration system was pressurized. It was known that the coagulated suspension under either charge-neutralization or sweep floc condition showed similar steady-state flux under the cross-flow microfiltration mode. Another report on the concept of critical floc size suggested that flocs need to reach a certain critical size before MF, otherwise membranes can be irreversibly clogged by the coagulant solids. The authors were motivated to study the effect of various coagulation conditions on the performance of a membrane filtration system.

Coagulation/flocculation/ultrafiltration for natural organic matter removal in drinking water production

2004 ◽  
Vol 4 (5-6) ◽  
pp. 215-222 ◽  
Author(s):  
A.R. Costa ◽  
M.N. de Pinho
Keyword(s):  
Drinking Water ◽  
Organic Matter ◽  
Natural Organic Matter ◽  
Membrane Fouling ◽  
Membrane Filtration ◽  
Membrane Surface ◽  
Water Production ◽  
Cellulose Acetate Membranes ◽  
Wide Range ◽  
Drinking Water Production

Membrane fouling by natural organic matter (NOM), namely by humic substances (HS), is a major problem in water treatment for drinking water production using membrane processes. Membrane fouling is dependent on membrane morphology like pore size and on water characteristics namely NOM nature. This work addresses the evaluation of the efficiency of ultrafiltration (UF) and Coagulation/Flocculation/UF performance in terms of permeation fluxes and HS removal, of the water from Tagus River (Valada). The operation of coagulation with chitosan was evaluated as a pretreatment for minimization of membrane fouling. UF experiments were carried out in flat cells of 13.2×10−4 m2 of membrane surface area and at transmembrane pressures from 1 to 4 bar. Five cellulose acetate membranes were laboratory made to cover a wide range of molecular weight cut-off (MWCO): 2,300, 11,000, 28,000, 60,000 and 75,000 Da. Severe fouling is observed for the membranes with the highest cut-off. In the permeation experiments of raw water, coagulation prior to membrane filtration led to a significant improvement of the permeation performance of the membranes with the highest MWCO due to the particles and colloidal matter removal.

Oil-in-water emulsion breaking marine bacteria for demulsifying oily wastewater

2019 ◽  
Vol 149 ◽  
pp. 292-301 ◽  
Author(s):  
Qinhong Cai ◽  
Zhiwen Zhu ◽  
Bing Chen ◽  
Baiyu Zhang
Keyword(s):  
Marine Bacteria ◽  
Oily Wastewater ◽  
Water Emulsion ◽  
Oil In Water ◽  
Oil In Water Emulsion

scholarly journals Changes in thermal stability of lignocelluloses waste aggregates long-term incorporated in composite

2021 ◽  
Vol 900 (1) ◽  
pp. 012042
Author(s):  
N Stevulova ◽  
A Estokova
Keyword(s):  
Thermal Stability ◽  
Alkaline Treatment ◽  
Cement Matrix ◽  
Scanning Calorimetry ◽  
Alkali Ions ◽  
Thermal Gravimetry ◽  
Pre Treatment ◽  
Surface Modified ◽  
Thermal Stability Of

Abstract This paper is addressed to comparative study of changes in thermal stability of surface-modified hemp-hurds aggregates long-term incorporated in bio-aggregate-based composites with the original ones before their integration into alternative binder matrix. In this study, the effectiveness of alkaline treatment of hemp hurds compared to the raw bio-aggregates as well as in relation to their behaviour when they are long-term incorporated in the MgO-cement environment is investigated. The differences in the thermal behaviour of the samples are explained by the changed structure of hemp hurds constituents due to the pre-treatment and long-term action of the alternative binder components on the bio-aggregates. Alkaline treatment increases thermal stability of hemp hurds compared to raw sample. Also long-term incorporation of hemp hurds in MgO-cement matrix had a similar effect in case of alkaline modified bio-aggregates. The more alkali ions present in the structure of hemp hurdssamples, the more ash is formed during their thermal decomposition studied by thermal gravimetry (TG) and differential scanning calorimetry (DSC).

Surface Modification of PEOT/PBT Membrane with Silk Fibroin Anchoring and its Potential Application in Artificial Salivary Gland Construct

2012 ◽  
Vol 538-541 ◽  
pp. 52-59
Author(s):  
Jie Zhu ◽  
Ming Shi Li ◽  
Li Qun Wang ◽  
Xiao Lin Zhu
Keyword(s):  
Salivary Gland ◽  
Silk Fibroin ◽  
Potential Application ◽  
Contact Angles ◽  
Water Contact ◽  
Polar Groups ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Surface Modified

We reported the preparation of surface modified poly (ethylene oxide terephthalate) - poly (butylene terephthalate) membrane by the method of silk fibroin anchoring, namely SF/(PEOT/PBT). Its surface properties were characterized by contact angles and XPS and the biocompatibility of the composite membrane was further evaluated by human salivary epithelial cells (HSG cells) growth in vitro. Results revealed that SF/(PEOT/PBT) possessed the low water contact angle (48.0±3.0°) and immobilized a great amount of fibroin (fibroin surface coverage: 26.39 wt%), which attributed to the formation of polar groups such as hydrosulfide group, sulfonic group, carboxyl and carbonyl ones in the process of SO2 plasma treatment. HSG cells growth in vitro indicated that the silk fibroin anchoring could significantly enhance the biocompatibility of PEOT/PBT membrane, which suggested the potential application of fibroin anchoring PEOT/PBT for clinical HSG cells transplantation in the artificial salivary gland construct.

Biomimetic Multilayer Nanofibrous Membranes with Elaborated Superwettability for Effective Purification of Emulsified Oily Wastewater

2018 ◽  
Vol 10 (18) ◽  
pp. 16183-16192 ◽  
Author(s):  
Jianlong Ge ◽  
Qing Jin ◽  
Dingding Zong ◽  
Jianyong Yu ◽  
Bin Ding
Keyword(s):  
Oily Wastewater ◽  
Nanofibrous Membranes
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