Solar Production of Hydrogen Using “Self-Assembled” Polyoxometalate Photocatalysts

2006 ◽  
Vol 128 (3) ◽  
pp. 326-330 ◽  
Author(s):  
N. Muradov ◽  
A. T-Raissi
Keyword(s):  
Cost Effective ◽  
Hydrogen Gas ◽  
Anion Exchange Resins ◽  
Colloidal Platinum ◽  
Production Of Hydrogen ◽  
Order Of Magnitude ◽  
Near Term ◽  
Exchange Resins ◽  
Water Alcohol Solutions ◽  
Water Alcohol

The near-term and cost-effective production of solar hydrogen from inexpensive and readily available hydrogen containing compounds (HCCs) can boost the prospects of future hydrogen economy. In this paper, we assess the prospects of the solar-assisted conversion of HCCs into hydrogen using polyoxometalate (POM) based photocatalysts, such as isopolytungstates (IPT) and silicotungstic acid (STA). Upon exposure to solar photons, IPT aqueous solutions containing various HCCs (e.g., alcohols, alkanes, organic acids, sugars, etc.) produce hydrogen gas and corresponding oxygenated compounds. The presence of small amounts of colloidal platinum increases the rate of hydrogen evolution by one order of magnitude. A solar photocatalytic flat-bed reactor, approximately 1.2m×1.2m in size, was fabricated and tested for the production of hydrogen from water-alcohol solutions containing IPT and STA and small amounts of colloidal Pt. The solar photoreactor tests demonstrated steady-state production of hydrogen gas for several days. IPT immobilized on granules of anion exchange resins with quaternary ammonium active groups show good photocatalytic activity for hydrogen production from water-alcohol solutions exposed to near-UV or solar radiation.

Solar Production of Hydrogen Using “Self-Assembled’’ Polyoxometalate Photocatalysts

Solar Energy ◽  
2005 ◽  
Author(s):  
Nazim Z. Muradov ◽  
Ali T-Raissi
Keyword(s):  
Cost Effective ◽  
Hydrogen Gas ◽  
Anion Exchange Resins ◽  
Colloidal Platinum ◽  
Production Of Hydrogen ◽  
Order Of Magnitude ◽  
Near Term ◽  
Exchange Resins ◽  
Water Alcohol Solutions ◽  
Water Alcohol

Near-term and cost-effective production of solar hydrogen from inexpensive and readily available hydrogen containing compounds (HCCs) can boost the prospects of future hydrogen economy. In this paper, we assess the prospects of solar-assisted conversion of HCCs into hydrogen using polyoxometalate (POM) based photocatalysts, such as isopolytunstates (IPT) and silicotungstic acid (STA). Upon exposure to solar photons, IPT aqueous solutions containing various HCCs (e.g. alcohols, alkanes, organic acids, sugars, etc.) produce hydrogen gas and corresponding oxygenated compounds. The presence of small amounts of colloidal platinum increases the rate of hydrogen evolution by one order of magnitude. A solar photocatalytic flat-bed reactor, approximately 1.2 m × 1.2 m in size, was fabricated and tested for production of hydrogen from water-alcohol solutions containing IPT and STA and small amounts of colloidal Pt. The solar photoreactor tests demonstrated steady-state production of hydrogen gas for several days. IPT immobilized on granules of anion exchange resins with quaternary ammonium active groups show good photocatalytic activity for hydrogen production from water-alcohol solutions exposed to near-UV or solar radiation.

scholarly journals Mg/Al double-metal hydroxide regeneration of anion exchange resin by electric field intensification

2016 ◽  
Vol 75 (6) ◽  
pp. 1309-1318 ◽  
Author(s):  
Ying Wang ◽  
Zhun Li ◽  
Yansheng Li ◽  
Zhigang Liu
Keyword(s):  
Electric Field ◽  
Anion Exchange ◽  
Exchange Resin ◽  
Ph Value ◽  
Anion Exchange Resin ◽  
Cost Effective ◽  
Regenerative Capacity ◽  
Metal Hydroxides ◽  
Anion Exchange Resins ◽  
Exchange Resins

Fouled anion exchange resins were regenerated by electric field intensification of Mg/Al double-metal hydroxides. Regenerative experiments were performed with varying voltages (10–30 V) and dosages of Mg/Al hydroxides (0.045–0.135 mol and 0.015–0.045 mol, respectively) for 1–5 h. Optimal results were obtained under the following regenerative conditions: 20 V, 4 h, and 0.09/0.03 mol of Mg/Al hydroxides. The maximum regenerative capacity of resins was increased to 41.07%. The regenerative mechanism was presented by Fourier-transform infrared spectrum of resins and Mg/Al hydroxides, and the regenerative degree was analyzed with respect to conductivity, pH value, and electric current. Mg/Al hydroxides were also recycled after the regeneration. This method was proven to be cost-effective and environmentally friendly.

Hydrogen Gas Production Using Aluminum Waste Cans Powder Produced by Disintegration Method

2020 ◽  
Vol 853 ◽  
pp. 228-234
Author(s):  
Seng Tat Lim ◽  
Sumathi Sethupathi ◽  
Abdulkareem Ghassan Alsultan ◽  
Loong Kong Leong ◽  
Yun Hin Taufiq-Yap
Keyword(s):  
Fossil Fuels ◽  
Fine Powder ◽  
Cost Effective ◽  
Production Method ◽  
Gas Production ◽  
Hydrogen Gas ◽  
Alkaline Condition ◽  
Hydrolysis Process ◽  
Production Of Hydrogen ◽  
Hydrolysis Of

Fossil fuels dependencies need to be stopped to safeguard the earth from further damage. This study focuses on the production of hydrogen (H2) gas using waste aluminum (Al) cans. Al waste cans were fed into disintegrator to produce fine powder. The hydrolysis performance of disintegrated powdered Al cans were compared with the commercial Al powder. The effect of different reaction temperatures (25 - 100°C); type of alkalis (NaOH, KOH and Ba (OH)2); and type of water sources (tap, deionized, ultrapure and distilled) for the hydrolysis process were analyzed. The Al powders were also characterized using different techniques to understand its behavior. It was found that powdered Al waste cans produced more H2 compared to commercial Al reported in the literature. The higher the reaction temperature, the higher the rate of H2 production. Deionized water maximizes the production of H2 compared to other types of water. Ba (OH)2 was found to be an unproductive alkaline for H2 production using powdered Al waste cans. The successful hydrolysis of powdered Al waste can in alkaline condition in this research has demonstrated as a cost-effective, clean and green alternative hydrogen production method.

I-V Characteristic and Performance of Three Electrode Alkaline Electrolyzer

2021 ◽  
Author(s):  
Diwakar Kafle ◽  
Sushil Dumre ◽  
Saroj Tripathi ◽  
Shankar Shrestha
Keyword(s):  
Hydrogen Production ◽  
Electricity Consumption ◽  
Cost Effective ◽  
Hydrogen Gas ◽  
Voltage Source ◽  
Promising Technique ◽  
Environment Friendly ◽  
Main Challenge ◽  
Production Of Hydrogen ◽  
And Performance

Abstract Hydrogen production by electrolysis of water is seen as a promising technique as it is environment friendly and it can use renewable energy source for the production of hydrogen gas. However, this technology has less than 4% contribution to the production of commercial hydrogen in the market. This is due to the high electricity consumption of the water splitting reaction. The main challenge to make this technology efficient and economically viable is to develop cost effective and highly efficient electrolyzer. Here we have developed a three electrode electrolyzer in which an extra electrode is inserted between conventional electrodes: cathode and anode. This novel electrolyzer utilizes an extra voltage source which reduces the overpotential and increases the anode current of the cell, which is responsible for the hydrogen production. Furthermore, we observed that, the operating resistance of the cell decreases under the application of the new voltage source. Our results demonstrate that the introduction of third electrode improves the performance of electrolysis by consuming less power as compared to the traditional or conventional two electrode electrolyzer system.

IV. The aluminium-iodine reaction

1880 ◽  
Vol 30 (200-205) ◽  
pp. 546-550
Keyword(s):  
Joint Action ◽  
Hydrogen Gas ◽  
Production Of Hydrogen ◽  
Ordinary Temperature ◽  
Metallic Aluminium ◽  
Iodine Reaction ◽  
Water Alcohol

About four years ago we pointed out a reaction of iodide of aluminium which, as far as we are aware, has no precise analogue in the science of chemistry, and which has led to the discovery of several volatile aluminium alcohols. It is well known that neither water, alcohol, nor ether is decomposed by metallic aluminium, and that each of these bodies will dissolve iodine without entering further into combination with it ; but we found that by the joint action of these two elements, it was possible to split up the above-mentioned liquids. Water, though forming a definite hydrate with the iodide of aluminium, is decomposed by it in the presence of an excess of the metal, hydrogen being evolved and aluminic hydrate formed. This takes place at the ordinary temperature. Alcohol in a similar manner is decomposed by the joint action of metallic aluminium and its iodide, with the ultimate production of hydrogen gas, aluminic ethylate, and varying amounts of aluminic iodoethylate proportional to the quantity of aluminic iodide employed. A small quantity of the iodide suffices to bring about the formation of a very large amount of the ethylate ; in fact, the process would be a continuous one, were it not that the solid products gradually put a stop to the reaction.

scholarly journals Electrolyzer Modeling and Real-Time Control for Optimized Production of Hydrogen Gas

2020 ◽  
Author(s):  
Benjamin Flamm ◽  
Christian Peter ◽  
Felix N. Büchi ◽  
John Lygeros
Keyword(s):  
Real Time ◽  
Nonlinear Models ◽  
Cost Effective ◽  
Hydrogen Gas ◽  
Real Time Control ◽  
Actual System ◽  
Thermal Dynamics ◽  
Time Operation ◽  
Effective Manner ◽  
Production Of Hydrogen

<pre>We present a method that operates an electrolyzer to meet the demand of a hydrogen refueling station in a cost-effective manner by solving a model-based optimal control problem. To formulate the underlying problem, we first conduct an experimental characterization of a Siemens SILYZER 100 polymer electrolyte membrane electrolyzer with \SI{100}{\kilo \watt} of rated power. We run experiments to determine the electrolyzer's conversion efficiency and thermal dynamics as well as the overload-limiting algorithm used in the electrolyzer. The resulting detailed nonlinear models are used to design a real-time optimal controller, which is then implemented on the actual system. Each minute, the controller solves a deterministic, receding-horizon problem which seeks to minimize the cost of satisfying a given hydrogen demand, while using a storage tank to take advantage of time-varying electricity prices and photovoltaic inflow. We illustrate in simulation the significant cost reduction achieved by our method compared to others in the literature, and then validate our method by demonstrating it in real-time operation on the actual system. </pre>

scholarly journals Electrolyzer Modeling and Real-Time Control for Optimized Production of Hydrogen Gas

2020 ◽  
Author(s):  
Benjamin Flamm ◽  
Christian Peter ◽  
Felix N. Büchi ◽  
John Lygeros
Keyword(s):  
Real Time ◽  
Nonlinear Models ◽  
Cost Effective ◽  
Hydrogen Gas ◽  
Real Time Control ◽  
Actual System ◽  
Thermal Dynamics ◽  
Time Operation ◽  
Effective Manner ◽  
Production Of Hydrogen

<pre>We present a method that operates an electrolyzer to meet the demand of a hydrogen refueling station in a cost-effective manner by solving a model-based optimal control problem. To formulate the underlying problem, we first conduct an experimental characterization of a Siemens SILYZER 100 polymer electrolyte membrane electrolyzer with 100 kW of rated power. We run experiments to determine the electrolyzer's conversion efficiency and thermal dynamics as well as the overload-limiting algorithm used in the electrolyzer. The resulting detailed nonlinear models are used to design a real-time optimal controller, which is then implemented on the actual system. Each minute, the controller solves a deterministic, receding-horizon problem which seeks to minimize the cost of satisfying a given hydrogen demand, while using a storage tank to take advantage of time-varying electricity prices and photovoltaic inflow. We illustrate in simulation the significant cost reduction achieved by our method compared to others in the literature, and then validate our method by demonstrating it in real-time operation on the actual system. </pre>

Removal of Hydrophobic and Hydrophilic Constituents by Anion Exchange Resin

1999 ◽  
Vol 40 (9) ◽  
pp. 207-214 ◽  
Author(s):  
J.-P. Croué ◽  
D. Violleau ◽  
C. Bodaire ◽  
B. Legube
Keyword(s):  
Molecular Weight ◽  
Anion Exchange ◽  
Water Source ◽  
Atomic Ratio ◽  
Size Exclusion ◽  
Salting Out ◽  
Anion Exchange Resins ◽  
Hydrophilic Character ◽  
Exchange Resins

The objective of this work was to compare the affinity of well characterized NOM fractions isolated from two surface waters with strong (gel matrix and macroporous matrix) and weak anion exchange resins (AER) using batch experiment conditions. The structural characterization of the fraction of NOM has shown that the higher the hydrophilic character, the lower the C/O atomic ratio, the lower the SUVA, the lower the aromatic carbon content and the lower the molecular weight. In general (not always), strong AER was more efficient to remove DOC than weak AER. For the same water source (Suwannee River), the higher the molecular weight of the NOM fraction, the lower the affinity with AER. Increasing the ionic strength favored the removal of the hydrophobic NOM fraction (“salting out” effect) while increasing the pH apparently reduced the removal of the hydrophilic NOM fraction. Results were discussed in terms of size exclusion, adsorption, anion exchange and also hydrophobic/hydrophilic repulsion.

Pound Wise and Penny Foolish? Weight Loss and The Dynamics of Health Care Spending

2011 ◽  
Vol 14 (2) ◽  
Author(s):  
Thomas G Koch
Keyword(s):  
Weight Loss ◽  
Cost Savings ◽  
Cost Effective ◽  
Economic Consequences ◽  
Health Care Spending ◽  
Order Of Magnitude ◽  
Dynamic Measures ◽  
The Cost ◽  
The Impact ◽  
The Relationship

Current estimates of obesity costs ignore the impact of future weight loss and gain, and may either over or underestimate economic consequences of weight loss. In light of this, I construct static and dynamic measures of medical costs associated with body mass index (BMI), to be balanced against the cost of one-time interventions. This study finds that ignoring the implications of weight loss and gain over time overstates the medical-cost savings of such interventions by an order of magnitude. When the relationship between spending and age is allowed to vary, weight-loss attempts appear to be cost-effective starting and ending with middle age. Some interventions recently proven to decrease weight may also be cost-effective.

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