Destruction of Organic Matter by Hydrogen Peroxide in the Presence of Pyrophosphate and Its Effect on Soil Specific Surface Area

1977 ◽  
Vol 41 (2) ◽  
pp. 340-342 ◽  
Author(s):  
Paolo Sequi ◽  
Roberto Aringhieri
Keyword(s):  
Hydrogen Peroxide ◽  
Organic Matter ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area

scholarly journals 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 ◽  
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.

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

1999 ◽  
Vol 40 (3) ◽  
pp. 83-89 ◽  
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.

scholarly journals INFLUENCE OF CONDITIONS OF SYNTHESIS OF COBALT AND MANGANESE OXIDES ON THEIR ABILITY TO CATALYTIC DECOMPOSITION OF HYDROGEN PEROXIDE

2020 ◽  
Vol 86 (8) ◽  
pp. 111-125
Author(s):  
Olexandr Ivanenko ◽  
Anatoliy Omel’chuk ◽  
Tamara Pavlenko ◽  
Yuliia Pohorenko ◽  
Valerii Bikov
Keyword(s):  
Hydrogen Peroxide ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Manganese Oxides ◽  
Diffraction Method ◽  
Catalytic Decomposition ◽  
Ammonia Solution ◽  
Cobalt Hydroxide ◽  
Hydroxy Compounds

Cobalt and manganese oxides and their complex oxide compositions were obtained by the sol-gel method using various precipitators(ammonia solution and HMTA). It was determined by X-ray diffraction method that both individual and co-precipitated hydroxo compounds after calcination at 400 °С form oxide phases of Co3O4 and Mn3O4 composition. Samples obtained by sedimentation with ammonia solution have a larger specific surface area than synthesized in HMTA solution. When calcined at 400 °C, the specific surface area for cobalt-containing samples sedimentated with ammonia solution decreases, and for samples sedimentated from HMTA solution - increases. The pore volume depends on the precipitator and changes little during calcination. For co-sedimentated and calcined at 400 °C samples, the specific surface area plays a significant role: the higher it is, the greater the catalytic ability of the sample to decompose hydrogen peroxide. On the SEM image of samples driedat 100 °C, sedimentated with ammonia solution, agglomeration of flat particles of gitrated oxides of cobalt and/or manganese of globular form is observed. For samples deposited in HMTA solution, SEM images are represented by agglomeration of particles in the form of planar layers. Calcination at 400 °C partially destroys the structure. Kinetic studies of the decomposition of hydrogen peroxide with theparticipation of the obtained samples indicate the first order of the reaction. Samples of cobalt hydroxide and co-sedimentated cobalt and manganese hydroxy compounds synthesized in HMTA solution showed the best ability to catalyze. The highest productivity (dm3 H2O2 of decomposed 1 g of catalyst) is inherent in samples of cobalt hydroxy compounds and its composition with manganese compounds synthesized by HMTA, after heat treatment at 100 °C. The ability of such samples to catalytic decomposition of hydrogen peroxide is estimated to be not less than 2.4 dm3 H2O2 (14 days). Compared to compounds synthesizedwith ammonia solution, they retain their activity for a longer time.

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

2021 ◽  
Author(s):  
Huifang Wu ◽  
Yu Jiang ◽  
Xiang Li ◽  
Jun Zhou ◽  
Xinyu Xu ◽  
...  
Keyword(s):  
Organic Matter ◽  
Water Treatment ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Ph Value ◽  
Polluted Water ◽  
Dynamic Filtration ◽  
Removal Efficiencies ◽  
Filtration Experiment

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.

The Makeup of Soil

2003 ◽  
Author(s):  
Robert E. White
Keyword(s):  
Organic Matter ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Continuous Distribution ◽  
Mineral Matter ◽  
Fine Earth ◽  
Soil P ◽  
Surface Areas ◽  
Specific Surface Areas

Minerals and organic matter comprise the solid phase of the soil. The geological origin of the soil minerals, and the input of organic matter from plants and ani­mals, are briefly discussed in section 1.2.1. A basic knowledge of the composition and properties of these materials is fundamental to understanding how a soil in­fluences the growth of grapevines. A striking feature of soil is the size range of the mineral matter, which varies from boulders (>600 mm diameter), to stones and gravel (600 to >2 mm diameter), to particles (<2 mm diameter)—the fine earth fraction. The fine earth fraction is the most important because of the type of miner­als present and their large surface areas. The ratio of surface area to volume de­fines the specific surface area of a particle. The smaller the size of an object, the larger is the ratio of its surface area to volume. This can be demonstrated by con­sidering spherical particles of radius 0.1 mm, 0.01 mm, and 0.001 mm (1 mi­crometer or micron, μm). The specific surface areas of these particles are 30, 300, and 3000 mm2/mm3, respectively. In practice, the specific surface area is mea­sured as the surface area per unit mass, which implies a constant particle density (usually taken as 2.65 Mg/m3). A large specific surface area means that more mol­ecules can be adsorbed on the surface. Representative values for the specific sur­face areas of sand, silt, and clay-size minerals are given in table 2.1. Note the large range in specific surface area, even for the clay minerals, from as little as 5 m2/g for kaolinite to 750 m2/g for Na-montmorillonite. Because specific surface areas are important, we need to know the size distri­bution of particles in the fine earth fraction. This is expressed as the soil’s texture. The types of minerals that make up the individual size fractions are also impor­tant because they too influence the reactivity of the surfaces. Both these topics are discussed here. All soils show a continuous distribution of particle sizes, called a frequency dis­tribution. This distribution relates the number (or mass) of particles of a given size to their actual size, measured by the diameter of an equivalent sphere.

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