Evaluation of omphacite and iron-coated omphacite as a water filtration medium

Abstract In this study, omphacite media were modified by roasting at high temperature. The optimal preparation conditions were as follows: the pH value was 1, concentration of FeCl3 was 2 mol/L, roasting temperature was 450 °C and roasting time was 2 h. The specific surface area, scanning electron microscopy, and EDS analysis were used to compare the unmodified and modified omphacite, and a dynamic filtration experiment was performed to treat the slightly polluted water. The analysis of characterization results revealed that, the surface structure of the modified omphacite filter media has changed greatly. Its surface is rough and potholes have increased, and the specific surface area and adsorption capacity are significantly increased. Results of the dynamic filtration experiment revealed that the average removal efficiencies of organic matter, TOC, and turbidity by quartz sand were 21.17%, 2.2%, and 94.5%. The average removal efficiencies of organic matter, TOC, and turbidity by unmodified omphacite were 23.46%, 26.7%, and 95.2%. The average removal efficiencies of organic matter, TOC, and turbidity by modified omphacite were 50.35%, 45.5%, and 96.3%. On the whole, the filtration performance of the modified omphacite filter column is the best among three filter columns, and the recovery of the backwashing performance is also better. HIGHLIGHT At present, no application of omphacite in sewage has been found.The development of omphacite filtration technology can not only provide new market hot spots for minerals in the East China Sea area, but also have a very positive value for improving water treatment technology and enhancing water treatment efficiency.It is the intersection of mineral processing and environmental science.

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Preparation of Sands Modified by Aluminous Salt and its Adsorption Capability of CD2+

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.130-134.856 ◽

2011 ◽

Vol 130-134 ◽

pp. 856-859

Author(s):

Chun Sheng Ding ◽

Yang Ping Fu ◽

Qian Fen Zhu ◽

Jing Fu

Keyword(s):

Specific Surface ◽

Surface Area ◽

Influencing Factors ◽

Removal Efficiency ◽

Specific Surface Area ◽

Quartz Sand ◽

Ph Value ◽

Alkaline Condition ◽

Initial Concentration ◽

Adsorption Capability

In this experiment quartz sand was chosen as a carrier to be coated by aluminous salt under alkaline condition, and then the specific surface area was tested, and the adsorption capability and Cd2+ removal influencing factors of modified sand were studied. The investigation results showed that the specific surface area of modified sand was 75.244m2/g which was 9.38 times of that of original sand; the removal efficiency of Cd2+ by aluminous salt modified sand reached 59% contrast to 39% of original sand with pH 7.00. It was also found that the removal efficiency of Cd2+ by the aluminous salt modified sand was reduced with the increase of initial concentration of Cd2+ solution, and was enhanced with the increase of pH value, the Cd2+ removal efficiency was almost 71% with pH 9.0.

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Comparative Analysis on Chemical Composition and Charcoal Characterization of Two Miscanthus Species

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.415-417.1265 ◽

2011 ◽

Vol 415-417 ◽

pp. 1265-1272

Author(s):

Wen Biao Zhang ◽

Wen Zhu Li ◽

Bing Song Zheng

Keyword(s):

Chemical Composition ◽

Specific Surface ◽

Water Content ◽

Surface Area ◽

Specific Surface Area ◽

Ph Value ◽

Perennial Grass ◽

Water Extract ◽

Carbonization Temperature ◽

Hot Water

Miscanthus is a highly productive, rhizomatous, C4 perennial grass that should be considered as an excellent active carbon precursor. This paper compares the charcoal characterization and chemical composition between M. sinensis and M. floridulus. Species differed in water content, hot water extract, 1% NaOH extract, organic solvent extract, cellulose, lignin and ash. Carbonization temperatures have effects on charcoal yields of Miscanthus, which ranged from 23.5% to 48.0% for M. sinensis and 11.3% to 37.2% for M. floridulus. Water content, charcoal density, pH value, and specific surface area of charcoal characterization varied between two species of Miscanthus. The specific surface area increased with the increase of carbonization temperature. The highest specific surface area of M. sinensis and M. floridulus was 351.74 m2g−1and 352.74 m2g−1, respectively, when the carbonization temperature was 800°C.

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Preparing of Silica Aerogel and Adsorption Performance on Nitrobenzene

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.512-515.1980 ◽

2012 ◽

Vol 512-515 ◽

pp. 1980-1985

Author(s):

Ya Jun Luo ◽

Xue Li ◽

Xiao Li Hu ◽

Deng Liang He ◽

Peng Lin

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Ph Value ◽

Adsorption Property ◽

Infrared Absorption Spectrum ◽

Nitrobenzene Solution ◽

Silica Source ◽

Electron Microscopes ◽

Scanning Electron Microscopes

SiO2aerogel is prepared under normal conditions by taking tetraethyl orthosilicate (TEOS) as the silica source, N-hexane as the displacer, trimethylchlorosilane hexane as the modifier and hydrolysis environment provided by hydrochloric acid and ammonia water. The effect of pH value, time, temperature, initial concentration on the adsorption of nitrobenzene by aerogel has been studied. The results show that the best range of the pH value for adsorption is 10.72. When adsorption time is 100 min, adsorption equilibrium can be reached. The best temperature for adsorption is 40 °C. The adsorption capacity becomes larger with the concentration increasing of the nitrobenzene solution. When the concentration reaches 500 mg/L, the adsorption reaches 32.402 mg/g. The adsorption equation matches Langmuir model. Scanning Electron Microscopes (SEM), infrared absorption spectrum and specific surface area measurements have shown that the adsorption property of SiO2aerogel for the nitrobenzene is related to cellular structure of the aerogel and large specific surface area.

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Obtaining of transition phases of alumina starting from sodium aluminate in Bayer process

Hemijska industrija ◽

10.2298/hemind110128018o ◽

2011 ◽

Vol 65 (3) ◽

pp. 271-277

Author(s):

Zoran Obrenovic ◽

Radislav Filipovic ◽

Marija Milanovic ◽

Ivan Stijepovic ◽

Ljubica Nikolic

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Ph Value ◽

Sodium Aluminate ◽

High Specific Surface Area ◽

Heterogeneous Structure ◽

Aluminate Solution ◽

Bayer Liquor ◽

Sodium Aluminate Solution

Transition (active) phases of alumina were synthesized starting from sodium aluminate solution prepared out of Bayer liquor. The neutralisation of sodium aluminate solution was performed by sulphuric acid. Powder X-ray diffraction (XRD), Fourier-transformed infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and low-temperature nitrogen absorption studies were employed to trace the formation of the transition phases of alumina. The results show that the properties of the powders (phase composition, morphology and specific surface area) are strongly influenced by the initial pH value of the system, as well as by the duration of neutralisation step. It is possible to obtain powders with heterogeneous structure with dominant phase of bayerite, gibbsite or boehmit by tuning the pH and concentration of the starting sodium aluminate solution. The transition (active) phases of alumina (?- and ?-alumina) with high specific surface area (264-373 m2/g) are formed through the thermal dehydratation of aluminium hydroxide (bayerite and gibbsite) and aluminium oxyhydroxide (boehmite or pseudoboehmite) at the temperature of 500?C. Namely, bayerite and pseudoboehmite transforms to ?-phase of alumina upon heating, while gibbsite transforms to ?-phase, maintaining the parent morphology.

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Physicochemical and Microstructural Properties of Red Muds under Acidic and Alkaline Conditions

Applied Sciences ◽

10.3390/app10092993 ◽

2020 ◽

Vol 10 (9) ◽

pp. 2993

Author(s):

Qingke Nie ◽

Youdong Li ◽

Guohui Wang ◽

Bing Bai

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Red Mud ◽

Ph Value ◽

Soil Layer ◽

Microstructural Properties ◽

Naoh Solution ◽

Red Muds ◽

Hcl Solution

The main purpose of this study was to characterize the mineral and chemical composition of typical red muds in China. Changes in the physicochemical and microstructural properties of red muds collected from the Shanxi and Shandong provinces were investigated after they were immersed in an alkaline NaOH or an acidic HCl solution for 7, 28, and 120 days. The results showed that red mud has a high cation exchange capacity and active physicochemical properties, which can be closely related to its extremely high alkalinity and complex microstructure. The neutralization of red mud with the HCl solution results in the release of Na+ from the red mud particles into the leachate and can effectively decrease the pH value of the filtrate. The neutralization process can result in a significant decrease in the liquid limit, plastic limit and plasticity index, whereas the opposite was observed for the different parameters after the addition of the NaOH solution. In this sense, acid neutralization can significantly improve the cementation property of the red mud. This result will increase the water permeability of the acid-treated soil layer and improve the growth ability of plants. The specific surface area of red mud immersed in the NaOH solution decreased, whereas the specific surface area of red mud immersed in the HCl solution increased. This study contributes to our understanding of red mud properties after the red mud has been subjected to acidic and alkaline treatments, and the results can provide insights into the safe disposal of red mud.

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Quantitative Characterization for the Micronanopore Structures of Terrestrial Shales with Different Lithofacies Types: A Case Study of the Jurassic Lianggaoshan Formation in the Southeastern Sichuan Basin of the Yangtze Region

Geofluids ◽

10.1155/2021/1416303 ◽

2021 ◽

Vol 2021 ◽

pp. 1-16

Author(s):

Weiwei Liu ◽

Kun Zhang ◽

Qianwen Li ◽

Zhanhai Yu ◽

Sihong Cheng ◽

...

Keyword(s):

Organic Matter ◽

Specific Surface ◽

Pore Structure ◽

Surface Area ◽

Specific Surface Area ◽

Pore Volume ◽

Sichuan Basin ◽

Parallel Plate ◽

Quantitative Characterization ◽

Southeastern Sichuan Basin

Due to the specificity of the geological background, terrestrial strata are widely distributed in the major hydrocarbon-bearing basins in China. In addition, terrestrial shales are generally featured with high thickness, multiple layers, high TOC content, ideal organic matter types, and moderate thermal evolution, laying a solid material foundation for hydrocarbon generation. However, the quantitative characterization study on their pore structure remains inadequate. In this study, core samples were selected from the Middle Jurassic Lianggaoshan Formation in the southeastern Sichuan Basin of the Upper Yangtze Region for analyses on its TOC content and mineral composition. Besides, experiments including oil washing, the adsorption/desorption of CO2 and nitrogen, and high-pressure mercury pressure experiments were carried out. The pore structure of different petrographic types of terrestrial shales can be accurately and quantitatively characterized with these works. The following conclusions were drawn: for organic-rich mixed shales and organic-rich clay shales, the TOC content is the highest; the pore volume, which is primarily provided by macropores and specific surface area, which is provided by mesopores, was the largest, thus providing more space for shale oil and gas reservation. The pores take on a shape either close to a parallel plate slit or close to or of an ink bottle. For organic-matter-bearing shales, both the pore volume and specific surface area are the second-largest and are provided by the same sized pores with organic-rich mixed shales. Its pores take on a shape approximating either a parallel plate slit or an ink bottle. Organic-matter-bearing mixed shales have the lowest pore volume and specific surface area; its pore volume is primarily provided by macropores, and the specific surface area by mesopores and the shape of the pores are close to an ink bottle.

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Removal efficiency and mechanism of bio-treated coking wastewater by catalytic ozonation using MnO2 modified with anionic precursors

Environmental Engineering Research ◽

10.4491/eer.2020.394 ◽

2020 ◽

Vol 26 (5) ◽

pp. 200394-0

Author(s):

Jie Zhang ◽

Ben Dong ◽

Ding Ding ◽

Shilong He ◽

Sijie Ge

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Catalytic Performance ◽

Catalytic Ozonation ◽

Relative Content ◽

Precipitation Method ◽

Coking Wastewater ◽

Physiochemical Properties ◽

Removal Efficiencies

In this paper, MnO2 catalyst were firstly prepared and modified by four kinds of anionic precursors (i.e., NO3-, AC-, SO42- and Cl-) through redox precipitation method. After that, bio-treated coking wastewater (BTCW) was prepared and employed as targeted pollutants to investigate the catalytic ozonation performance of prepared-MnO2 catalyst was investigated and characterized by the removal efficiencies and mechanism of the prepared bio-treated coking wastewater (BTCW), which was employed as the targeted pollutants. Specifically, the effects of specific surface area, crystal structure, valence state of Mn element and lattice oxygen content on catalytic activity of MnO2 materials were characterized by BET, XRD and XPS, respectively. Results showed that COD of BTCW could be removed 47.39% under MnO2-NO3- catalyst with 2 h reaction time, which was much higher than that of MnO2-AC- (3.94%), MnO2-SO42- (12.42%), MnO2-Cl- (12.94%) and pure O3 without catalyst (21.51%), respectively. So, MnO2-NO3- presented the highest catalytic performance among these catalysts. The reason may be attributed to a series of better physiochemical properties including the smaller average grain, the larger specific surface area and active groups, more crystal defect and oxygen vacancy, higher relative content of Mn3+ and adsorbed oxygen (Oads) than that of another three catalysts.

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Three-Dimensional Hierarchical Porous Carbon Derived from Natural Resources for Highly Efficient Treatment of Polluted Water

10.21203/rs.3.rs-443489/v1 ◽

2021 ◽

Author(s):

Jiaxin Li ◽

Rudolf Holze ◽

Simbarashe Moyo ◽

Song Wang ◽

Sanxi Li ◽

...

Keyword(s):

Specific Surface ◽

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Surface Area ◽

Specific Surface Area ◽

Porous Carbon ◽

Polluted Water ◽

Hierarchical Porous Carbon ◽

Hierarchical Porous

Abstract In this work, a series of three-dimensional (3D) porous carbon nanomaterial with large specific surface area and hierarchical pores were selectively prepared from biomass with varied properties obtained by tuning the carbonization temperature and activation agent. The optimized carbon sample (PC-500-6) exhibits a typical hierarchical porous structure with a high specific surface area (3203 m2/g) and pore size distribution in the range 0.8 to 3.0 nm, which shows excellent adsorption performance for methylene blue (MB) from an aqueous solution. The maximum adsorption capacity even reaches 917.43 mg/g, which is among one of the best results up to now. Through analysis of the adsorption data, it is found that the corresponding adsorption kinetic fits the pseudo-second-order model very well. The present results demonstrate that biomass-derived hierarchical porous carbon has a real potential application for wastewater treatment.Background:Dealing with the ever-increasing water pollution has become an urgent global problem, especially the organic containing polluted water. The physical adsorption has become one of the most popular ways for removal of organic dyes from wastewater due to its low cost as well as high efficiency. However, the adsorption performance is still limited by the low specific surface area (SSA) and unsuitable pore size. Hence, it is still a challenge to synthesize active carbon (AC) with high SSA, suitable pore size distribution as well as low cost for polluted water treatment. Here, we report an efficient method to prepare AC with large SSA from jujube for removal of MB in aqueous solution. The present results demonstrate that biomass-derived hierarchical porous carbon has a real potential application for wastewater treatment.Results:The as-prepared hierarchical porous structure carbon material (PC-500-6) shows a high specific surface area (3203 m2/g) and pore size distribution in the range 0.8 to 3.0 nm, while exhibits an enhanced adsorption performance for methylene blue (MB) from an aqueous solution. The maximum adsorption capacity even reaches 917.43 mg/g, which was calculated from Langmuir model. Through analysis of the adsorption data, it is found that the corresponding adsorption kinetic fits the pseudo-second-order model very well.Conclusions:It can be concluded that the adsorption of MB has a strong correlation with SSA, pore size distribution as well as the pore volume. The present study paved a practical way for wastewater treatment by using biomass-derived hierarchical porous carbon.

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Polyamide-6 surface cracked forms nanofibers: A novel way for increasing the surface roughness, and porosity

10.21203/rs.3.rs-879988/v1 ◽

2021 ◽

Author(s):

Sedigheh Aghayari

Keyword(s):

Surface Roughness ◽

Water Treatment ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Pore Volume ◽

Polyamide 6 ◽

Bet Method ◽

Before And After ◽

The Web

Abstract Here away used to reduce the porosity of the nanofibers, which is removing PVA nanofibers from PVA/PA6 nanofibers by water treatment. Measuring the porosity of the electrospun web before and after treatment by the BET method proved this. The specific surface area of the web was 60 % reduced after water treatment. Surface roughness and pore volume have reduced after water treatment. Also, I introduced BET as the method for measuring the diameters of mesopores (or lower than 100nm). I used BET to prove that the cracks can make mesopores on the nanofibers.

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Assessment of Effective Specific Surface Area for Free Water Surface Constructed Wetlands

Water Science & Technology ◽

10.2166/wst.1999.0142 ◽

1999 ◽

Vol 40 (3) ◽

pp. 83-89 ◽

Cited By ~ 8

Author(s):

N. R. Khatiwada ◽

C. Polprasert

Keyword(s):

Organic Matter ◽

Specific Surface ◽

Surface Area ◽

Constructed Wetlands ◽

Specific Surface Area ◽

Kinetic Models ◽

Water Surface ◽

Free Water ◽

Organic Matter Degradation ◽

Biofilm Bacteria

Biofilm bacteria attached to submerged surfaces play a major role in organic matter degradation in free-water-surface(FWS) constructed wetlands used for wastewater treatment. Effective specific surface area (as) available for the biofilm bacteria is an important parameter in organic matter degradation and in describing the biofilm kinetic models used in the design and operation of constructed wetlands. In this study, kinetic models based on two possible biofilm geometries were developed for the determination of as and its non-dimensionalised value or area factor (δ). The as and δ values were estimated for a laboratory FWS constructed wetland treating domestic wastewater based on the chemical oxygen demand (COD) removal performance and other kinetic parameters. With the assumption of slab geometry for the biofilm, the values of as and δ were found as 3.15 m2/m3 and 2.2 for the lab unit having 80% mass COD removal, whereas by considering the cylindrical geometry for the biofilm attached on the lateral roots higher values of as and δ were obtained.

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