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Development of spinel sol bonded high pure alumina castable composition

A cement free high pure alumina[url=https://www.hslabrasive.com/]HSL factory[/url] castable composition is developed for high temperature applications using synthesized Mg-Al spinel sol as binder. The spinel sol is prepared from nitrate precursors and characterized for its pH, solid content, particle size, FTIR, thermal behavior (DSC-TG), phase formation with temperature (XRD), microstructure (FESEM), etc. High alumina castable formulations with different particle size distributions (PSDS) are conventionally processed using the synthesized sol as sole binder at two different amounts. Castables were characterized for various refractory properties after heat treatment at different temperatures. The hot strength and the corrosion resistance of the best composition are evaluated and the properties are compared with silica sol bonded high alumina castable with similar formulations, processed under similar conditions. [url=https://www.hslabrasive.com/products/fused-alumina/brown-fused-alumina.html]brown fused alumina HSL[/url]Considerable improvement in terms of hot strength, corrosion resistance and thermal shock resistance are obtained for the spinel sol bonded composition.

Alumina powder/Bis-GMA composite: effect of filler content on mechanical properties and osteoconductivity

Three composites consisting of alumina[url=https://www.hslabrasive.com/]hslabrasive[/url] powder dispersed in a bisphenol-a-glycidyl methacrylate (Bis-GMA) matrix were prepared and evaluated to assess the effect of alumina powder content on the mechanical properties and osteoconductivity of the composite. The alumina powder composites (APC) consisted of alumina powder (AL-P) as the inorganic filler dispersed in a Bis-GMA matrix that was solidified by a radical polymerization process. Prior to polymerization the AL-P was mixed with the monomers in proportions of 50%, 70%, and 80% by weight (APC50, APC70, and APC80). A fused silica-glass-filled composite containing 70% glass by weight (SGC70) was used as a control. The compressive and bending strengths, the elastic modulus in bending, and the bending strain of the composites increased as the AL-P content increased. We also evaluated the composites in vivo by implanting them into the medullary canals of rat tibiae. To compare the osteoconductivity of the composites, an affinity index was calculated for each composite; the affinity index equals the length of a bone in direct apposition to the composite and is expressed as a percentage of the total length of the composite surface. Microradiographic examination for periods of up to 26 weeks after implantation revealed that APC50, APC70, and APC80 all exhibited excellent osteoconductivity and made direct contact with the bone with no interposed soft tissues. However, the higher the AL-P content of the composite, the higher the osteoconductivity, especially at 4 weeks after the operation. Moreover, the amount of bone directly apposed to the composite surface increased with time. In contrast, little bone formation was seen on the surface of SGC70, even after 26 weeks. Observation by scanning electron microscope-energy dispersive X-ray microanalysis demonstrated that bone made direct contact with the APC surface through a layer containing calcium, phosphorus, and alumina powder. [url=https://www.hslabrasive.com/products/fused-alumina/brown-fused-alumina.html]fused alumina abrasive[/url]These results suggest that APC shows promise as a basis for developing mechanically strong and highly osteoconductive composites.

Effect of presence of ions on surface characteristics of surfactant modified powdered activated carbon (PAC)

Modification of surface characteristics of solids using surfactants has practical implications in industrial and environmental applications. Extensive research has been conducted to explore the mechanism of surfactant sorption to different solid surfaces. However, a clear understanding yet to be found especially for heterogeneous surfaces in which pores and structure show local differences. The main objective of this study was to determine the effects of ions on the surface potential of surface modified activated carbon. In order to achieve the objective, anionic and cationic surfactants were selected and adsorptions of these surfactants to powdered activated carbon (PAC[url=https://www.powdered-activated-carbon.com/]powdered activated carbon size[/url] were investigated. Then, zeta potential measurements were conducted for the surface modified PAC and finally, the effects of mono- and di-valent anions and cations on the zeta potentials of PAC surface were investigated. The results showed that even at very low cetyl trimethyl ammonium bromide (CTAB) concentrations charge reversal was observed and substantial increase was observed in zeta potential. However, linearalkyl benzene sulfonate (LABS) showed somewhat gradual decrease in zeta potential, reaching maximum when maximum sorption capacity was attained. Presence of anions in addition to CTAB effected the change of zeta potential. Similar effects were also observed for LABS modified PAC in the presence of mono- and di-valent cations. The change of zeta potential of with the valance of cations and anions were linear.[url=https://www.activated-carbon-pellets.com/]activated carbon pellets for air filter au[/url]

Mesoporous activated coconut shell-derived hydrochar prepared via hydrothermal carbonization-NaOH activation for methylene blue adsorption

Mesoporous activated coconut shell-derived hydrochar prepared via hydrothermal carbonization-NaOH activation for methylene blue adsorption[url=https://www.chinactivecarbon.com/products/coconut-carbon-gold.html]coconut shell activated carbon for gold mine[/url] Mesoporous activated carbon was prepared using a hydrochar derived from coconut shell waste through hydrothermal carbonization and NaOH chemical activation process (COSHTC). Three sets of activated carbons were obtained with different hydrochar:NaOH impregnation ratios (1:1, 1:2, and 1:3). Among these ratios, 1:3 (COSHTC3) exhibited the optimum adsorption for methylene blue (MB). COSHTC3 adsorbed MB with an initial concentration of 25-250 mg/L at pH 3-11 and 30 °C. The adsorption isotherm of MB on COSHTC3 demonstrated that Langmuir isotherm could be better applied at a maximum monolayer adsorption capacity of 200.01 mg/g at 30 °C. The data was well fitted to the pseudo-second-order (PSO) kinetic model. These results show that the COSHTC3 prepared from low-cost agricultural waste (coconut shell) [url=https://www.chinactivecarbon.com/]www.chinactivecarbon.com[/url]with average pore diameter 28.6 Å and surface area 876.14 m2/g acts as a better adsorbent for removal of cationic dyes and could pave the way for more low-cost adsorbents for dye removal.

Adsorption of humic acid by powdered activated carbon in saline water conditions

The adsorption of humic acid (HA) by powdered activated carbon (PAC) [url=https://www.powdered-activated-carbon.com/]powdered activated carbon cost[/url]in saline waters has been examined in the absence and presence of metal salt coagulants. The study showed that adsorption of HA by PAC can be significantly greater in saline water compared to freshwater and low conductivity water. An optimal adsorption was attained at saline concentrations corresponding to synthetic seawater diluted to 12.5–25% of its original concentration. In undiluted synthetic seawater the adsorption of HA from solution by PAC was comparable with that of local tap water in terms of initial adsorption rate and total removal. The enhanced adsorption is believed to be a combination of reduced electrostatic repulsion between the HA and PAC at high salt concentrations, and chemisorption due to chemical bonding between the functional groups. The effects of adding a metal salt coagulant, either aluminium sulphate or ferric chloride, on overall HA removal were found to depend strongly on the coagulant dose, solution pH and the sequence of addition of the PAC and metal salt coagulant. Addition of the PAC shortly before the coagulant was found to give the greatest removal of HA.The adsorption of humic acid (HA) by powdered activated carbon (PAC) in saline waters has been examined in the absence and presence of metal salt coagulants. The study showed that adsorption of HA by PAC can be significantly greater in saline water compared to freshwater and low conductivity water. An optimal adsorption was attained at saline concentrations corresponding to synthetic seawater diluted to 12.5–25% of its original concentration. In undiluted synthetic seawater the adsorption of HA from solution by PAC[url=https://www.granular-activated-carbon.com/]activated carbon granule manufacturers in china[/url] was comparable with that of local tap water in terms of initial adsorption rate and total removal. The enhanced adsorption is believed to be a combination of reduced electrostatic repulsion between the HA and PAC at high salt concentrations, and chemisorption due to chemical bonding between the functional groups. The effects of adding a metal salt coagulant, either aluminium sulphate or ferric chloride, on overall HA removal were found to depend strongly on the coagulant dose, solution pH and the sequence of addition of the PAC and metal salt coagulant. Addition of the PAC shortly before the coagulant was found to give the greatest removal of HA.

Honeycomb-like hierarchical carbon derived from livestock sewage sludge as oxygen reduction reaction catalysts in microbial fuel cells

Cathode catalysts with excellent efficiencies, low costs and long-term durability in microbial fuel cell (MFC) applications have attracted considerable attention. Herein, hierarchically structured carbons with[url=https://www.wyactivatedcarbon.com/products/other-activated-carbon/honeycomb-activated-carbon.html]honeycomb active carbon[/url]honeycomb-like interconnected macro-mesoporous frameworks and N, P, and Fe heteroatom doping have been successfully prepared through direct pyrolysis from livestock sewage sludge. In neutral media, the as-prepared activated livestock sewage sludge carbon (LSC-A) catalyst displayed great electrocatalytic activity for the oxygen reduction reaction (ORR), and a maximum power density of 1273 ± 3 mW/m2 was obtained when this catalyst applied in MFCs, which is comparable to that of commercial Pt/C (1294 ± 2 mW/m2). Furthermore, after 90 days of operation, the voltage output of the MFC with the LSC-A cathode decreased only 10.2%, which is considerably lower than the 28.4% decrease of the Pt/C cathode, indicating that LSC-A possesses a greater long-term stability than the Pt/C cathode. This study demonstrated that the N, P, Fe-doped honeycomb-like hierarchically structured carbon derived from livestock sewage sludge is a cost-efficient and promising cathode catalyst for scaling up MFCs[url=https://www.wyactivatedcarbon.com/]https://www.wyactivatedcarbon.com/[/url]

Optimized synthesis of granular fuel and granular activated carbon from sawdust hydrochar without binder

In this study, a facile and eco-friendly method for synthesis of granular fuel and granular activated carbon[url=https://www.coconutactivatedcarbon.com/]largest activated carbon manufacturers[/url]was developed. The approach needs not to add a harmful binder due to inherent characteristics of sawdust hydrochar and has not been previously reported. Granular fuel was prepared from densification of sawdust hydrochar acquired from hydrothermal carbonization. Sawdust hydrochar was also pelletized and activated with FeCl3 and ZnCl2 to obtain granular activated carbon. The effects of the temperature used for the hydrothermal carbonization process on the characteristics of granular fuel and granular activated carbon were investigated. The results showed that at the optimal temperature of 230 °C, the high heat value, energy density, and equilibrium moisture content of granular fuel were 23.53 MJ/kg, 35.87 GJ/m3, and 0.73%. Equilibrium moisture content was improved about 7 times compared to sawdust. In addition, the hydrothermal carbonization temperature was negatively correlated with the Brunauer-Emmett-Teller surface area and the iodine adsorption value of granular activated carbon. The compression strength of granular activated carbon was excellent (up to 8.8 MPa), which was high enough to use in adsorption bed. For optimal granular fuel and granular activated carbon properties, the best temperature was found to be 230 °C, and the Brunauer-Emmett-Teller surface area and the iodine adsorption value of granular activated carbon were 641 m2/g and 626 mg/g. As the environmental problems acquire increasingly attentions, the granular fuel and granular activated carbon[url=https://www.activated-carbon-pellets.com/]4mm air purification activated carbon pellets[/url] could be promising and eco-friendly materials for future applications.

Development of activated carbon pellets using a facile low-cost binder for effective malachite green dye removal

Activated carbon pellet (ACP) is advantageous to the industrial-based adsorption process owing to its easy handling, large volumetric adsorption capacity and good mechanical properties. This study introduces a straightforward phosphoric acid-impregnated sawdust as economical binder to convert textile sludge activated carbon powder into water resistant pellets. The effects of activation time and drying technique on the physicochemical and mechanical properties of ACPs were investigated. The materials were characterized using N2 gas adsorption-desorption, scanning electron microscope, Boehm titration, pHpzc and compressive strength test. It was discovered that the physiochemical properties of ACPs were close to that of base activated carbon.[url=https://www.coconutactivatedcarbon.com/]largest activated carbon manufacturers[/url]Moreover, a longer activation time promotes the development of micropore on ACPs and enhances the compressive strength. The microporosity, surface area and compressive strength of ACPs are in the range of 16–23%, 668–979 m2/g and 0.4–1.5 MPa, respectively. The ACP prepared at 560 °C for 3 h showed a 395 mg/g of malachite green removal, whilst retaining its cylindrical shape. The Langmuir model gave the best conformity to the equilibrium data, suggesting a possible monolayer adsorption onto ACPs. [url=https://www.activated-carbon-pellets.com/]4mm air purification activated carbon pellets[/url] This study demonstrated the potential of sawdust as low-cost binder and the applicability of ACPs in dye adsorption.

A new honeycomb carbon monolith for CO2 capture by rapid temperature swing adsorption using steam regeneration

[url=https://www.wyactivatedcarbon.com/products/other-activated-carbon/honeycomb-activated-carbon.html]honeycomb active carbon[/url]A rapid process for CO2 capture is of key importance for the economic feasibility of the process in industry, consequently short adsorption/desorption cycles are crucial. With this aim in mind, a carbon based honeycomb monolith was evaluated for CO2 capture in a thermal swing adsorption process at short contact times. The effect of (1) regeneration time, (2) presence of water vapor during adsorption and desorption and (3) regeneration method (steam versus hot air) on CO2 adsorption was studied. The monolith was characterized in terms of porosity and CO2, N2, and H2O isotherms. Cyclic adsorption/desorption experiments were performed using different synthetic gas mixtures with concentrations of CO2 ranging between 6 and 15 vol%. The effect of water vapor in the synthetic gas mixture on adsorption capacity was limited but increases with relative humidity. Steam of 120 °C was used to heat the monolith and desorb CO2. Advantages of steam usage are the facile separation of steam and concentrated CO2 and the low (waste) heating energy cost of steam. It was demonstrated that the steam allows very fast heating and cooling of the monolith.[url=https://www.wyactivatedcarbon.com/]https://www.wyactivatedcarbon.com/[/url] However, the presence of residual condensation water after the cooling step reduces the cyclic adsorption capacity, requiring an additional drying step with hot or cold air.

Effect of powdered activated carbon on Chinese traditional medicine wastewater treatment in submerged membrane bioreactor with electronic control backwashing

Effect of powdered activated carbon on Chinese traditional medicine wastewater treatment in submerged membrane bioreactor with electronic control backwashing [url=https://www.granular-activated-carbon.com/]activated carbon granule manufacturers in china[/url]Chinese traditional medicine wastewater, rich in macromolecule and easy to foam in aerobic biodegradation such as Glycosides, was treated by two identical bench-scale aerobic submerged membrane bioreactors (SMBRs) operated in parallel under the same feed, equipped with the same electronic control backwashing device. One was used as the control SMBR (CSMBR) while the other was dosed with powdered activated carbon (PAC) (PAC-amended SMBR, PSMBR). The backwashing interval was 5 min. One suction period was about 90 min by adjusting preestablished backwashing vacuum and pump frequency. The average flux of CSMBR during a steady periodic state of 24 d (576 h) was 5.87 L/h with average hydraulic residence time (HRT) of 5.97 h and that of PSMBR during a steady periodic state of 30 d (720 h) was 5.85 L/h with average HRT of 5.99 h. The average total chemical oxygen demand (COD) removal efficiency of CSMBR was 89.29% with average organic loading rate (OLR) at 4.16 kg COD/(m3-d) while that of PSMBR was 89.79% with average OLR at 5.50 kg COD/(m3-d). COD concentration in the effluent of both SMBRs achieved the second level of the general wastewater effluent standard GB8978–1996 for the raw medicine material industry (300 mg/L). Hence, SMBR with electronic control backwashing was a viable process for medium- strength Chinese traditional medicine wastewater treatment. Moreover, the increasing rates of preestablished backwashing vacuum, pump frequency, and vacuum and flux loss caused by mixed liquor in PSMBR all lagged compared to those in CSMBR; thus the actual operating time of the PSMBR system without membrane cleaning was extended by up to 1.25 times in contrast with the CSMBR system,[url=https://www.powdered-activated-carbon.com/]powdered activated carbon cost[/url] and the average total COD removal efficiency of PSMBR was enhanced with higher average OLR.


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