scholarly journals Surface-Modified Nanofibrous PVDF Membranes for Liquid Separation Technology

Materials ◽  
2019 ◽  
Vol 12 (17) ◽  
pp. 2702 ◽  
Author(s):  
Evren Boyraz ◽  
Fatma Yalcinkaya ◽  
Jakub Hruza ◽  
Jiri Maryska
Keyword(s):  
Tio2 Nanoparticles ◽  
Polyvinylidene Fluoride ◽  
Cost Effective ◽  
Second Step ◽  
Separation Technology ◽  
New Type ◽  
Oil Water ◽  
Green Separation ◽  
Surface Modified ◽  
Near Future

Preparing easily scaled up, cost-effective, and recyclable membranes for separation technology is challenging. In the present study, a unique and new type of modified polyvinylidene fluoride (PVDF) nanofibrous membrane was prepared for the separation of oil–water emulsions. Surface modification was done in two steps. In the first step, dehydrofluorination of PVDF membranes was done using an alkaline solution. After the first step, oil removal and permeability of the membranes were dramatically improved. In the second step, TiO2 nanoparticles were grafted onto the surface of the membranes. After adding TiO2 nanoparticles, membranes exhibited outstanding anti-fouling and self-cleaning performance. The as-prepared membranes can be of great use in new green separation technology and have great potential to deal with the separation of oil–water emulsions in the near future.

Biosurfactants as demulsifying agents for oil recovery from oily sludge – performance evaluation

2013 ◽  
Vol 67 (12) ◽  
pp. 2875-2881 ◽  
Author(s):  
Evans M. N. Chirwa ◽  
Tshepo Mampholo ◽  
Oluwademilade Fayemiwo
Keyword(s):  
Oil Recovery ◽  
Sodium Dodecyl ◽  
Cost Effective ◽  
Solid Particles ◽  
Second Step ◽  
Oily Sludge ◽  
Waste Sludge ◽  
Complex Interactions ◽  
Oil Water ◽  
Living Organisms

The oil producing and petroleum refining industries dispose of a significant amount of oily sludge annually. The sludge typically contains a mixture of oil, water and solid particles in the form of complex slurry. The oil in the waste sludge is inextractible due to the complex composition and complex interactions in the sludge matrix. The sludge is disposed of on land or into surface water bodies thereby creating toxic conditions or depleting oxygen required by aquatic animals. In this study, a fumed silica mixture with hydrocarbons was used to facilitate stable emulsion (‘Pickering’ emulsion) of the oily sludge. The second step of controlled demulsification and separation of oil and sludge into layers was achieved using either a commercial surfactant (sodium dodecyl sulphate (SDS)) or a cost-effective biosurfactant from living organisms. The demulsification and separation of the oil layer using the commercial surfactant SDS was achieved within 4 hours after stopping mixing, which was much faster than the 10 days required to destabilise the emulsion using crude biosurfactants produced by a consortium of petrochemical tolerant bacteria. The recovery rate with bacteria could be improved by using a more purified biosurfactant without the cells.

scholarly journals Enriched Catalytic Activity of TiO2 Nanoparticles Supported by Activated Carbon for Noxious Pollutant Elimination

Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2808
Author(s):  
Suriyaprabha Rajendran ◽  
Gajendra Kumar Inwati ◽  
Virendra Kumar Yadav ◽  
Nisha Choudhary ◽  
Mitesh B. Solanki ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Activated Carbon ◽  
Tio2 Nanoparticles ◽  
Dye Degradation ◽  
Cost Effective ◽  
Pure Tio2 ◽  
Textile Dye ◽  
Sonochemical Method ◽  
Bet Analysis ◽  
Surface Modified

Cleaning wastewater has become one of the most serious issues for a number of scientists and researchers in recent years, as water is the most basic need for the daily life of humans. There has been a focus on the removal of noxious pollutants from wastewater effluents by using nanocatalysts owing to their unique physicochemical actions and stability. Herein we manufactured TiO2 nanoparticles supported by activated carbon (AC-TiO2) using a cost-effective sonochemical method. The band structures of the AC-TiO2 and TiO2 were modified from 3.2 to 3.1 eV, thus increasing the catalytic activity. The structural, optical and anatase crystal phase properties, with morphological confirmation, were studied by applying UV-DRS, PL, FESEM, XRD, along with HRTEM, respectively. The specific surface area, calculated by BET analysis, was found to be ~241 m2/gm and ~46 m2/gm for AC-TiO2 and TiO2. The degradation efficiency of the as-prepared nanocatalysts against the very toxic but rarely studied organic textile dye pollutant RO 84 was investigated and 97% efficiency were found for the AC-TiO2 as compared to pure TiO2, which is a highly appreciated finding in the catalytic dye degradation application domain. Such surface-modified nanocatalysts could be further implemented for the treatment of wastewaters/waste effluents released from chemical industries, laboratories and other sources.

scholarly journals Novel PVDF-PVP Hollow Fiber Membrane Augmented with TiO2 Nanoparticles: Preparation, Characterization and Application for Copper Removal from Leachate

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 399
Author(s):  
Mohammed Umar Abba ◽  
Hasfalina Che Man ◽  
Raba’ah Syahidah Azis ◽  
Aida Isma Idris ◽  
Muhammad Hazwan Hamzah ◽  
...  
Keyword(s):  
Contact Angle ◽  
Adsorption Capacity ◽  
Tio2 Nanoparticles ◽  
Polyvinylidene Fluoride ◽  
Negative Impact ◽  
Hollow Fiber Membrane ◽  
Copper Removal ◽  
Fiber Membrane ◽  
Copper Adsorption ◽  
Phase Inversion Technique

High proportion of copper has become a global challenge owing to its negative impact on the environment and public health complications. The present study focuses on the fabrication of a polyvinylidene fluoride (PVDF)-polyvinyl pyrrolidone (PVP) fiber membrane incorporated with varying loading (0, 0.5, 1.0, 1.5, and 2.0 wt%) of titanium dioxide (TiO2) nanoparticles via phase inversion technique to achieve hydrophilicity along with high selectivity for copper removal. The developed fibers were characterized based on scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), permeability, porosity, zeta potential, and contact angle. The improved membrane (with 1.0 wt% TiO2) concentration recorded the maximum flux (223 L/m2·h) and copper rejection (98.18%). Similarly, 1.0 wt% concentration of TiO2 nanoparticles made the membrane matrix more hydrophilic with the least contact angle of 50.01°. The maximum copper adsorption capacity of 69.68 mg/g was attained at 1.0 wt% TiO2 concentration. The experimental data of adsorption capacity were best fitted to the Freundlich isotherm model with R2 value of 0.99573. The hybrid membrane developed in this study has considerably eliminated copper from leachate and the concentration of copper in the permeate was substantially reduced to 0.044 mg/L, which is below standard discharge threshold.

Oil, Water, Slag Three Phases Separation Technology of Heavy Aging Oil

2014 ◽  
Vol 936 ◽  
pp. 1553-1555
Author(s):  
Meng Zheng
Keyword(s):  
Water Content ◽  
Field Test ◽  
Oil Recovery ◽  
Recovery Rate ◽  
Storage Capacity ◽  
Quality Requirements ◽  
Separation Technology ◽  
Oil Water ◽  
Export Quality ◽  
Three Phases

The technology was used for handling heavy aging oil by demulsifier and three phases horizontal scrow centrifuge. Through laboratory and field test, it showed that the water content of the processed aging oil dropped from 50% to 5% below, purity oil recovery rate reached more than 95%, meeting export quality requirements. The technology improved the effective storage capacity of flow station, is of great significance to the safe and steady operation of flow station.

Preparation and properties of short oil alkyd resin/TiO2 nanocomposites based on surface modified TiO2 nanoparticles

2016 ◽  
Vol 39 (5) ◽  
pp. 1488-1499 ◽  
Author(s):  
Tijana S. Radoman ◽  
Jasna V. Džunuzović ◽  
Pavle M. Spasojević ◽  
Milena T. Marinović-Cincović ◽  
Katarina B. Jeremić ◽  
...  
Keyword(s):  
Tio2 Nanoparticles ◽  
Alkyd Resin ◽  
Surface Modified

Synthesis of Silica Modified Large-Sized Hydroxyapatite Whiskers by a Hydrothermal Co-Precipitation Method

2015 ◽  
Vol 645-646 ◽  
pp. 1339-1344 ◽  
Author(s):  
Yan Ting Yin ◽  
Qing Hua Chen ◽  
Ting Ting Yan ◽  
Qing Hua Chen
Keyword(s):  
Bone Repair ◽  
Ethanol Solution ◽  
Morphological Properties ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
New Type ◽  
Ft Ir ◽  
Co Precipitation ◽  
Surface Modified

The objective of this study was to develop a novel silica modified large-sized hydroxyapatite whiskers with improved properties for use in bone repair applications. Large-sized whiskers with a mean length of 250μm were obtained by a hydrothermal co-precipitation method at 150°C, 7.5Mpa in high-pressure reactor. Silica modified hydroxyapatite whiskers were prepared by dissolving TEOS in ethanol solution, then sintering with hydroxyapatite. The compositional and morphological properties of prepared whiskers were studied by means of x-ray diffraction (XRD), Fouier transform infrared (FT-IR), scanning electron microscopy (SEM). The results indicated the evidence of nanosilicon dioxide particles on the surface of HAP whiskers. The size of nanosilicon dioxide particles depends on dropping and stirring rate. Hence, this new type of silica modified large-sized hydroxyapatite whiskers is a valuable candidate for biomedical applications.Key words: hydroxyapatite, hydrothermal co-precipitation, surface modified, whiskers

scholarly journals ToU Pricing-Based Dynamic Electricity Theft Detection in Smart Grid Using Gradient Boosting Classifier

2021 ◽  
Vol 11 (1) ◽  
pp. 401
Author(s):  
Rajiv Punmiya ◽  
Sangho Choe
Keyword(s):  
Smart Grid ◽  
Dynamic Pricing ◽  
Gradient Boosting ◽  
Core Concept ◽  
Actual Usage ◽  
Electricity Theft ◽  
Extreme Gradient Boosting ◽  
New Type ◽  
Near Future ◽  
Very High

In the near future, it is highly expected that smart grid (SG) utilities will replace existing fixed pricing with dynamic pricing, such as time-of-use real-time tariff (ToU). In ToU, the price of electricity varies throughout the whole day based on the respective utilities’ decisions. We classify the whole day into two periods with very high and low probabilities of theft activities, termed as the “theft window” and “non-theft window”, respectively. A “smart” malicious consumer can adjust his/her theft to mostly targeting the theft window, manipulate actual usage reporting to outsmart existing theft detectors, and achieve the goal of “paying reduced tariff”. Simulation results show that existing schemes do not detect well such window-based theft activities conversely exploiting ToU strategies. In this paper, we begin by introducing the core concept of window-based theft cases, which is defined at the basis of ToU pricing as well as consumption usage. A modified extreme gradient boosting (XGBoost) based machine learning (ML) technique called dynamic electricity theft detector (DETD) has been presented to detect a new type of theft cases.

Initial properties and ageing behaviour of pineapple leaf and palm fibre as reinforcement for polypropylene

2016 ◽  
Vol 30 (2) ◽  
pp. 174-195 ◽  
Author(s):  
Rungsima Chollakup ◽  
Haroutioun Askanian ◽  
Florence Delor-Jestin
Keyword(s):  
Mechanical Properties ◽  
Cost Effective ◽  
Tensile Tests ◽  
Natural Fibre ◽  
Thermal Ageing ◽  
Second Step ◽  
Scanning Calorimetry ◽  
Ultraviolet Exposure ◽  
Palm Fibre

In the furniture, automotive and contruction industries, there is increased demand for cost-effective and lightweight biocomposites. The objective of this work was to develop new natural fibre-based composites with specific properties. Palm and pineapple leaf fibres were chosen in association with polypropylene (PP). The first step was to investigate the effect of these natural fibres as reinforcement for PP. The evolution of chemical structure and crystallinity was proposed with infrared spectroscopy measurements and differential scanning calorimetry thermograms, respectively. The assessments of mechanical properties with tensile tests and melt viscoelastic behaviour were also investigated. The study enabled to distinguish the influence of fibre content. The second step in our work was to assess the composite durability after ultraviolet exposure or thermal ageing. The oxidation level was calculated. The long-term evolution of thermal and mechanical properties was also proposed. As a result, the PP/pineapple leaf composite revealed a promising biocomposite.

Sign in / Sign up

Export Citation Format

Share Document