Hydrogen production by the hydrolysis of milled waste magnesium scraps in nickel chloride solutions and nickel chloride added in Marmara Sea and Aegean Sea Water

2015 ◽  
Vol 40 (46) ◽  
pp. 16169-16177 ◽  
Author(s):  
Aysel Kantürk Figen ◽  
Bilge Coşkuner Filiz
Keyword(s):  
Hydrogen Production ◽  
Sea Water ◽  
Aegean Sea ◽  
Nickel Chloride ◽  
Marmara Sea ◽  
Chloride Solutions ◽  
Hydrolysis Of

HYDROGEN FROM HYDROGEN SULPHIDE IN BLACK SEA

2019 ◽  
pp. 49-55
Author(s):  
S. Z. Baykara ◽  
E. H. Figen ◽  
A. Kale ◽  
T. N. Veziroglu
Keyword(s):  
Hydrogen Production ◽  
Black Sea ◽  
Hydrogen Sulphide ◽  
Sea Water ◽  
Economic Value ◽  
Environmental Pollutant ◽  
The Black Sea ◽  
Fuel Processing ◽  
Acid Gas ◽  
Reducing Bacteria

Hydrogen sulphide, an acid gas, is generally considered an environmental pollutant. As an industrial byproduct, it is produced mostly during fuel processing. Hydrogen sulphide occurs naturally in many gas wells and also in gas hydrates and gas-saturated sediments especially at the bottom of the Black Sea where 90% of the sea water is anaerobic.The anoxic conditions exist in the deepest parts of the basin since nearly 7300 years, caused by the density stratification following the significant influx of the Mediterranean water through the Bosphorous nearly 9000 years ago. Here, H2S is believed to be produced by sulphur reducing bacteria at an approximate rate of 10 000 tons per day, and it poses a serious threat since it keeps reducing the life in the Black Sea. An oxygen–hydrogen sulphide interface is established at 150–200 m below the surface after which H2S concentration starts increasing regularly until 1000 m, and finally reaches a nearly constant value of 9.5 mg/l around 1500 m depth.Hydrogen sulphide potentially has economic value if both sulphur and hydrogen can be recovered. Several methods are studied for H2S decomposition, including thermal, thermochemical, electrochemical, photochemical and plasmochemical methods.In the present work, H2S potential in the Black Sea is investigated as a source of hydrogen, an evaluation of the developing prominent techniques for hydrogen production from H2S is made, and an engineering assessment is carried out regarding hydrogen production from H2S in the Black Sea using a process design based on the catalytic solar thermolysis approach. Possibility of a modular plant is considered for production at larger scale.

scholarly journals Spring and surface water quality of the Cyprus ophiolites

2002 ◽  
Vol 6 (5) ◽  
pp. 797-817 ◽  
Author(s):  
C. Neal ◽  
P. Shand
Keyword(s):  
Water Quality ◽  
Sea Water ◽  
Stream Water ◽  
Chemical Reactivity ◽  
Surface Water Quality ◽  
Calcium Sulphate ◽  
Stream Water Quality ◽  
Troodos Ophiolite ◽  
High Calcium ◽  
Hydrolysis Of

Abstract. A survey of surface, spring and borehole waters associated with the ophiolite rocks of Cyprus shows five broad water types (1) Mg-HCO3, (2) Na-SO4-Cl-HCO3, (3) Na-Ca-Cl-SO4-OH-CO3, (4) Na-Cl-SO4 and (5) Ca-SO4. The waters represent a progression in chemical reactivity from surface waters that evolve within a groundwater setting due to hydrolysis of the basic/ultrabasic rock as modified by CO2-weathering. An increase in salinity is also observed which is due to mixing with a saline end-member (modified sea-water) and dissolution of gypsum/anhydrite. In some cases, the waters have pH values greater than 11. Such high values are associated with low temperature serpentinisation reactions. The system is a net sink for CO2. This feature is related not only to the hydrolysis of the primary minerals in the rock, but also to CaCO3 or Ca-Mg-CO3 solubility controls. Under hyperalkaline conditions, virtually all the carbon dioxide is lost from the water due to the sufficiently high calcium levels and carbonate buffering is then insignificant. Calcium sulphate solubility controls may also be operative when calcium and sulphate concentrations are particularly high. Keywords: Cyprus, Troodos, ophiolite, serpentinisation, spring, stream, water quality, bromide, iodine, boron, trace elements, hyperalkaline.

scholarly journals Research on hydrogen generation from rapid hydrolysis of aluminum in sodium fluoride solution

2019 ◽  
Vol 118 ◽  
pp. 03048
Author(s):  
Changchun Li ◽  
Yuxin Wu
Keyword(s):  
Hydrogen Production ◽  
Kinetic Model ◽  
Sodium Fluoride ◽  
Hydrogen Generation ◽  
Hydrogen Yield ◽  
Shrinking Core Model ◽  
Fluoride Solution ◽  
Shrinking Core ◽  
Rapid Hydrolysis ◽  
Hydrolysis Of

Hydrogen generation from rapid hydrolysis of aluminum in sodium fluoride solution was investigated through a hydrolysis experiment. Rapid and instant hydrogen yield were observed using sodium fluoride as additive. The experimental results demonstrate that the increase of temperature and the amount of additives in a certain range will boost the hydrogen production. The amount of additives outside the range only has an effect on the rapid hydrolysis of the aluminum during the initial stage, but the total amount of hydrogen produced doesn’t increased significantly. Theoretical analysis of the effects of the mixing ratio and the temperature on the hydrogen production rates were performed using the shrinking core model and the kinetic model. The shrinking core model parameter a and k indicate the film change degree of porosity and thickness and the effect of time on the diffusion coefficient. the kinetic model is verified and the activation energy confirming hydrogen yield control by a molecular diffusion process. Correspondingly, mechanisms of Al corrosion in NaF solutions under low and high alkalinity were proposed, respectively.

scholarly journals Influence of solid–acid catalysts on steam reforming and hydrolysis of dimethyl ether for hydrogen production

2006 ◽  
Vol 304 ◽  
pp. 40-48 ◽  
Author(s):  
Kajornsak Faungnawakij ◽  
Yohei Tanaka ◽  
Naohiro Shimoda ◽  
Tetsuya Fukunaga ◽  
Shunichiro Kawashima ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Dimethyl Ether ◽  
Steam Reforming ◽  
Solid Acid ◽  
Solid Acid Catalysts ◽  
Acid Catalysts ◽  
Hydrolysis Of

Measuring the Sea: Marsili’s Oceanographic Cruise (1679–80) and the Roots of Oceanography

2018 ◽  
Vol 48 (4) ◽  
pp. 845-860 ◽  
Author(s):  
Nadia Pinardi ◽  
Emin Özsoy ◽  
Mohammed Abdul Latif ◽  
Franca Moroni ◽  
Alessandro Grandi ◽  
...  
Keyword(s):  
Adriatic Sea ◽  
Aegean Sea ◽  
Experimental Methodology ◽  
Marmara Sea ◽  
Numerical Studies ◽  
Measurement Methodology ◽  
Geographical Position ◽  
Layer Flow ◽  
Current Inversion

ABSTRACTThe first in situ measurements of seawater density that referred to a geographical position at sea and time of the year were carried out by Count Luigi Ferdinando Marsili between 1679 and 1680 in the Adriatic Sea, Aegean Sea, Marmara Sea, and the Bosporus. Not only was this the first investigation with documented oceanographic measurements carried out at stations, but the measurements were described in such an accurate way that the authors were able to reconstruct the observations in modern units. These first measurements concern the “specific gravity” of seawaters (i.e., the ratio between fluid densities). The data reported in the historical oceanographic treatise Osservazioni intorno al Bosforo Tracio (Marsili) allowed the reconstruction of the seawater density at different geographic locations between 1679 and 1680. Marsili’s experimental methodology included the collection of surface and deep water samples, the analysis of the samples with a hydrostatic ampoule, and the use of a reference water to standardize the measurements. A comparison of reconstructed densities with present-day values shows an agreement within 10%–20% uncertainty, owing to various aspects of the measurement methodology that are difficult to reconstruct from the documentary evidence. Marsili also measured the current speed and the depth of the current inversion in the Bosporus, which are consistent with the present-day knowledge. The experimental data collected in the Bosporus enabled Marsili to enunciate a theory on the cause of the two-layer flow at the strait, demonstrated by his laboratory experiment and later confirmed by many analytical and numerical studies.

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