scholarly journals Improvement of Polytetrafluoroethylene Membrane High-Efficiency Particulate Air Filter Performance with Melt-Blown Media

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4067
Author(s):  
Euijin Shim ◽  
Jeong-Phil Jang ◽  
Jai-Joung Moon ◽  
Yeonsang Kim
Keyword(s):  
High Efficiency ◽  
High Weight ◽  
Average Particle Size ◽  
Initial Pressure ◽  
Average Particle ◽  
Air Conditioner ◽  
Air Filter ◽  
Ptfe Membrane ◽  
Filter Performance ◽  
Actual Use

Polytetrafluoroethylene (PTFE) membrane filters are widely used in low-load application areas, such as industrial cleanrooms, due to their low initial pressure drop. In this study, melt-blown (MB) nonwoven was introduced as a pre-filtration layer at the front end of a high-efficiency particulate air (HEPA) filter to improve the filter performance of the PTFE membrane. Pre-filtration reduces the average particle size, which reaches the PTFE membrane and reduces the dust load on the HEPA filters. A comparative analysis of the HEPA filters by composite MB and PTFE was conducted. Regarding the MB composite on the PTFE, low-weight and high-weight MB composites were effective in increasing dust filtration efficiency, and the dust loading capacity of the PTFE composite with high-weight MB increased by approximately three times that of the PTFE membrane. In addition, the filter was installed on an external air conditioner in an actual use environment and showed a high efficiency of 99.984% without a change in differential pressure after 120 days.

PENGARUH LAJU PREKURSOR SERBUK ALUMINIUM TERHADAP BENTUK MORFOLOGI NANOPARTIKEL ALUMINA DENGAN METODE THERMAL PLASMA

ROTOR ◽  
2017 ◽  
Vol 10 (1) ◽  
pp. 17
Author(s):  
Havid Arifian Rochman ◽  
Arief Ginanjar Dirgantara ◽  
Salahudin Junus ◽  
Imam Sholahuddin ◽  
Aris Zainul Muttaqin
Keyword(s):  
Particle Size ◽  
Aluminum Powder ◽  
Thermal Plasma ◽  
High Efficiency ◽  
Average Particle Size ◽  
Alumina Nanoparticles ◽  
Rate Variation ◽  
Average Particle ◽  
Dc Plasma ◽  
Simple Method

The synthesis of nanoparticles using thermal DC plasma method is a simple method for ease of installation and high efficiency is due to the rate of precursor that can be controlled. Micro-sized aluminum powder is synthesized using thermal DC plasma undergoing a process of evaporation as it passes through high temperature plasma flame, where kemuadian oxidized aluminum particles which evaporates the particles are split and binds with oxygen to form aluminum oxide or also known as alumina (Al2O3). In this experiment, the flow rate of oxygen plasma parameters at 35 SCFH (Standard Cubic Feet per Hour) and 20 amperes flows with precursors rate variation of 1.16 g / min, 3.19 g / min, and 3.5 g / min. Precursors used is 88 micro sized aluminum powder. To determine the morphology of nanoparticles of alumina testing scanning electron microscopy (SEM), the morphology form of nanosphere. Results of the analysis showed that the rate of precursor low causing agglomeration level slightly while the higher rate of precursor agglomeration rate also increased. At the rate of precursor 1.16 g / min, nanoparikel undergo agglomeration with an average particle size of 36.55 nm, and then at a rate of 3.19 gr precursor / mnt an average particle size of 46.49 nm, and at a rate of 3.5 gr / mnt an average particle size of 46.49 nm. The powder nanoparticles were then characterized using X-ray defraksi (XRD) where all alumina nanoparticles were synthesized showed alumina phase that is formed is a phase δ-Al2O3. Keywords: Alumina nanoparticles, DC Thermal Plasma, morphology, precursor rate, nanoparticles size, SEM, XRD.

scholarly journals A New Collector for Effectively Increasing Recovery in Copper Oxide Ore-Staged Flotation

Minerals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 595
Author(s):  
Renfeng Zhu ◽  
Guohua Gu ◽  
Zhixiang Chen ◽  
Yanhong Wang ◽  
Siyu Song
Keyword(s):  
Particle Size ◽  
Copper Oxide ◽  
High Efficiency ◽  
Average Particle Size ◽  
Economic Feasibility ◽  
Processing Plant ◽  
Average Particle ◽  
Entrainment Rate ◽  
Flotation Process ◽  
New Type

A new method, staged flotation for effectively increasing the recovery of ultra-fine copper oxide ore with a new type of collector (ZH-1, C3-5 carbon chain xanthate) is proposed for the first time. The flotation process and mechanism were examined by flotation tests, entrainment rate analysis, laser particle size experiments and microscopic imagery as well as economic feasibility analysis. It was demonstrated that the collector isoamyl sodium xanthate (ISX) shows a good collection ability (recovery exceeded 95%) for azurite, but the recovery was relatively much lower for malachite (only near 80%) due to the different particle size distribution. The new type of xanthate ZH-1 has shown a high-efficiency collection performance for fine-grained malachite. The recovery achieved for −10 μm malachite was more than 95% when the ZH-1 dosage was 150 mg/L, while the average particle size of −10 μm malachite sharply increased from 4.641 μm to 9.631 μm. The batch flotation results indicated that the copper oxide flotation recovery increased from 79.67% to 83.38%, and the grade also raised from 18.08% to 18.14% after using the staged flotation technology with ZH-1 as collector during the flotation of −25 μm ore. It was confirmed that this technology was quite effective for the recovery of copper oxide at the Dishui Copper Processing Plant, which successfully increased its gross profit by 1.6 million US$ per year.

scholarly journals Anomalocardia brasiliana shellfish shells as a novel and ecofriendly adsorbent of Nylosan Brilliant Blue acid dye

2018 ◽  
Vol 78 (7) ◽  
pp. 1576-1586 ◽  
Author(s):  
Tarsila Maíra Nogueira de Paiva ◽  
Tiago José Marques Fraga ◽  
Davyson Cesar S. Sales ◽  
Marilda Nascimento Carvalho ◽  
Maurício Alves da Motta Sobrinho
Keyword(s):  
Electrostatic Interactions ◽  
High Efficiency ◽  
Average Particle Size ◽  
Physical Nature ◽  
Freundlich Isotherm ◽  
Brilliant Blue ◽  
Point Of Zero Charge ◽  
Maximum Adsorption Capacity ◽  
Average Particle ◽  
Acid Dye

Abstract Malacoculture waste (Anomalocardia brasiliana) shellfish shells (ABSS) were evaluated as adsorbents of Nylosan Brilliant Blue (NBB) acid dye. The ABSS were thermally activated at 1,000 °C for 10 h and then characterized by Fourier-transform infrared spectroscopy, analysis of specific surface area (BET), X-ray diffraction (XRD), and scanning electron microscopy. Point of zero charge (PZC) analysis of ABSS verified pHPZC 13.0. The study of kinetics showed that the pseudo-second-order model fit the experimental data best and the system reached equilibrium within 5 min. Adsorption isotherms followed the Langmuir–Freundlich isotherm and ABSS reached an outstanding maximum adsorption capacity of 405 mg·g−1 under the following optimum conditions: pH 12.4, 303 K, 450 rpm, 2.0 g of adsorbent, and 150 μm average particle size. These conditions were obtained after a previous statistical analysis of the variables. Enthalpy and Gibbs energy obtained in the thermodynamics experiments were −23.79 kJ·mol−1 and −4.07 kJ·mol−1, respectively. These parameters confirm that the process is exothermic, spontaneous, and indicative of the physical nature of the adsorption. The adsorption of NBB onto ABSS tended to be more favorable at a lower temperature. Low value of enthalpy suggested that weak binding forces, such as electrostatic interactions, govern the sorption mechanism. ABSS high availability in the environment, its low toxicity and high efficiency make it a promising ecofriendly adsorbent of textile dyes.

scholarly journals Low-Temperature Adsorption Study of Carbon Dioxide on Porous Magnetite Nanospheres Iron Oxide

2021 ◽  
Vol 12 (5) ◽  
pp. 6252-6268
Keyword(s):  
Adsorption Isotherms ◽  
High Efficiency ◽  
Co2 Adsorption ◽  
Average Particle Size ◽  
Total Pore Volume ◽  
Spherical Shape ◽  
Bet Surface Area ◽  
Average Particle ◽  
Type I ◽  
Magnetite Fe3o4

Porous magnetite Fe3O4 nano-spheres (PMNs) have been successfully produced and have been demonstrated to be high-efficiency adsorbents. The PMNs have a spherical shape with an average particle size of 25.84 nm. The BET surface area of PMNs is 143.65 m2g-1, with a total pore volume of 0.16 cm3g-1. As a result of CO2 adsorption and desorption features on dry PMNs, this synthesized material is projected to be exploited as possible CO2 sequestration reservoirs to minimize greenhouse gas emissions. CO2 adsorption was best at low temperatures and with dry PMNs. PMNs, on the other hand, has a very high adsorption capacity of 0.96 mmol/g. According to the IUPAC categorization of adsorption isotherms, all CO2 adsorption isotherms of coal samples fall into type I, which most likely indicates adsorption restricted to a few layers of molecules (micropores and mesopores). Langmuir, Henry, Dubbin, Temkin, Toth, Harkin-Jura, Elovich, Redlich Peterson, and Josene models suit any experimental adsorption data that best predict the heterogeneous surface features of PMNs.

Preparation and Characterization of Silicone Oil/UF Resin Microcapsules as Erosion Inhibitor

2016 ◽  
Vol 723 ◽  
pp. 481-485 ◽  
Author(s):  
Hong Guang Li ◽  
Shao Sen Lin ◽  
Shi Guo Du ◽  
De Jiang Lin
Keyword(s):  
Particle Size ◽  
High Efficiency ◽  
In Situ Polymerization ◽  
Silicone Oil ◽  
Average Particle Size ◽  
Weight Ratio ◽  
Polymerization Process ◽  
Core Material ◽  
Molar Ratio ◽  
Average Particle

Microcapsules with silicone oil as core and poly (urea-formaldehyde) as shell were prepared by direct in-situ polymerization process. The influences of formaldehyde-urea molar ratios on microcapsules morphologies were investigated by scanning electron microscope (SEM). The microcapsules were characterized by fourier transform infrared spectrometer (FT-IR), particle size analyzer, simultaneous thermal analyzer. The results showed that well dispersive microcapsules were obtained with average particle size of 2.5 μm when formaldehyde-urea molar ratio was 1.8:1.0 and that the weight ratio of silicon dioxide to microcapsule was 15.4%, which produced from pyrolysis of core material silicone oil. The prepared microcapsules were expected to a kind of high-efficiency erosion inhibitor when used in propellant.

scholarly journals Studies various factors effecting the synthesis of submicron silicon dioxide particles by leaching from waste dumps of the Balaklavskoe deposit

2021 ◽  
Vol 2057 (1) ◽  
pp. 012137
Author(s):  
V A Turyanskiy ◽  
G A Baranov ◽  
T V Chayka ◽  
V M Gavrish
Keyword(s):  
Silicon Dioxide ◽  
High Efficiency ◽  
Solid Phase ◽  
Average Particle Size ◽  
Precipitation Process ◽  
Average Particle ◽  
Waste Dumps ◽  
Dioxide Powder ◽  
Soda Solution ◽  
Silicon Dioxide Content

Abstract The paper presents the results of studies of the main parameters of synthesis of silicon dioxide powder from Balaklava deposit sludge with silicon dioxide content of 24%. During the study caustic soda solution is used as a leaching agent and sulfuric acid was used as a precipitant. At the leaching stage the concentration of leaching agent, the ratio of liquid phase to solid phase, the optimum temperature of leaching as well as the mode of pulp agitation are investigated. At the precipitation stage, the following parameters are considered: concentration of precipitating agent and temperature of the precipitation process. As a result of using the optimal parameters the high efficiency of obtaining silica powder of 98.56% is achieved. Average particle size is 200-800 nm, and agglomerate size is more than 800 nm.

scholarly journals Effective Removal of Amido Black and Eosin B Dyes in Aqueous Solution by MWCNT/ZrO2/Pb Nanocomposites: Isotherm, Reusability and Kinetic Studies

2021 ◽  
Author(s):  
Marjan Sheibani ◽  
Mehrorang Ghaedi ◽  
Vahid Zare-Shahabadi ◽  
Arash Asfaram
Keyword(s):  
Aqueous Solution ◽  
High Efficiency ◽  
Average Particle Size ◽  
Theoretical Data ◽  
Kinetic Studies ◽  
Average Particle ◽  
Operational Conditions ◽  
Eosin B ◽  
Amido Black ◽  
Multi Walled Carbon Nanotubes

This research illustrates modification of multi-walled carbon nanotubes (MWCNT) by ZrO2/Pb to construct nanocomposites (MWCNT/ZrO2/Pb-NCs) by simple precipitation technique and subsequently examine its ability for adsorption of Amido black (AB) and Eosin B (EB) dyes in binary system. The present nanocomposites investigation by FESEM, XRD, FTIR, and EDX analysis, reveal its as-synthesized crystalline nature with cubic morphology and average particle size 30–50 nm. The present nano-adsorbent represent high efficiency for AB and EB adsorption from aqueous solution, while dependency of variables including pH, initial concentration of dyes, contact time and MWCNT/ZrO2/Pb-NCs mass were analyzed by central composite design (CCD). The predicted maximum removal percentage was 95% removal for both dyes is consequence of adjustment of operational conditions at pH of 6.0; 0.05 g MWCNT/ZrO2/Pb-NCs; 15 min stirring at 15 mg L-1 for both dyes. The Langmuir as applicable for representation and description of reveal data of adsorption with adsorption capacity of 15.46 and 16.92 mg g-1 for AB and EB, respectively. Pseudo-first order model owing to its high correlation coefficient and closeness of experimental and theoretical data well represented behavior of corresponding adsorption system. Mechanism examination strongly proof high contribution of external mass transference as the main rate-controlling step. The successful regeneration of MWCNT/ZrO2/Pb-NCs suggested their usefulness in wastewater treatment and its ability of environmental management.

scholarly journals Description, Kinetic and Equilibrium Studies of the Adsorption of Carbon Dioxide in Mesoporous Iron Oxide Nanospheres

2021 ◽  
Vol 12 (1) ◽  
pp. 1022-1038
Keyword(s):  
Iron Oxide ◽  
High Efficiency ◽  
Co2 Adsorption ◽  
Average Particle Size ◽  
Bet Surface Area ◽  
Average Particle ◽  
Equilibrium Studies ◽  
Spherical Form ◽  
Best Fit

Mesoporous iron oxide nanospheres (MINs) have been successfully synthesized and have proven to be high-efficiency adsorbents. The morphology of the MINs is very uniform in spherical form, with an average particle size of 23-27 nm in the diameter range. MINs content has a fairly high BET surface area of 188.25 m2g−1 and a total volume of 0.14 cm3g−1 pores. Thus, seams were seen as potential CO2 sequestration reservoirs to reduce greenhouse gas emissions. The CO2 adsorption was favorable at low temperature and dry MINs conditions. However, MINs have a high adsorption capacity of 0.15 mmol/g. The CO2 adsorption isotherm of all coal samples according to the IUPAC classification of adsorption isotherms fits category I, which most likely explains adsorption confined to a few layers of molecules (micropores and mesopores). The balancing assessment using Langmuir, Henry, Dubbin, Temkin, Toth, Harkins-Jura, Elovich, Redlich-Peterson, and Josene model provided the best fit for any experimental adsorption data that predict heterogeneous surface properties of MINs.

Photodegradation of 2-Naphthalenesulfonate in Aqueous Catalyzed by N-Doped TiO2 under Irradiation of Simulated Solarlight

2011 ◽  
Vol 356-360 ◽  
pp. 471-475
Author(s):  
Guo Qing Liu ◽  
Le Chen ◽  
Yu Ping Wang ◽  
Pan Ying Peng
Keyword(s):  
Visible Light ◽  
Nitrogen Doping ◽  
High Efficiency ◽  
Anatase Phase ◽  
Sol Gel ◽  
Average Particle Size ◽  
Average Particle ◽  
Light Sources ◽  
Band Gap Narrowing ◽  
Very High

N/TiO2photocatalyst was synthesized by modified sol–gel method and characterized by XRD, XPS and DRS. The photoactivity of N/TiO2were evaluated by the degradation of 2-naphthalenesulfonate (2-NS) under different light sources. The results showed that nitrogen doping may cause band gap narrowing of TiO2, and therefore increase the photocatalytivity of N/TiO2under visible-light. The average particle size of the N/TiO2synthesized is about 10 nm, and the N/TiO2contains 100% anatase phase of TiO2. The dopant is found mainly to be NOx and the doping concentration in NT is 1.30%. The NT shows very high efficiency for the catalysis of the degradation of 2-NS. The degradation efficiency of 2-NS using NT under visible light for 5 h is 47.29%, much higher than 2.5% of the pure TiO2.

A Study on Novel Gas Atomization Device for Preparing Ultra Fine Metal Powder

2011 ◽  
Vol 291-294 ◽  
pp. 741-744
Author(s):  
Xin An Dang ◽  
Li Li Wang ◽  
Li Jun Yang
Keyword(s):  
Particle Size ◽  
Magnetic Particles ◽  
High Efficiency ◽  
Surface Effect ◽  
Average Particle Size ◽  
Average Particle ◽  
Good Prospect ◽  
Gas Atomization ◽  
Metal Powders ◽  
Two Fluids

On the basis of technologies of gas atomization, supersonic gas atomization, surface effect of electric charge and jet, we design a new-style device of two fluids atomization with the combination of solid atomization and electric field utilizing a LAVAL nozzle, a delivery tube of sectional type and the electrical field dispersion technique. The soldering tin of 63 A was atomized with the air, and the powder prepared was analyzed by optical granularity analyzer, nanometer magnetic particles and Zeta potential analyzer. The results show that the particle size with less than 8μm can reach 75%; the average particle size is 1.7612μm, and the first peak in the distribution curve is about 500 nm, which is an order of magnitude smaller than that the existing reported peak. The compound atomization device can refine the particle size of powers effectively, improve uniformity, yielding rate, and the purity of atomized powders and has a significant effect on atomizing, thus provides powerful supports for preparing ultra fine metal powders with high efficiency and low energy consumption and has a good prospect in application.

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