[en] Human history reveals again and again lost moments of history. Had they been recognized, the world would have taken another - better - course. The point of transition to hydrogen and solar energy is another such historical moment. The primary energy supply oriented 20th century is coming to a close. The useful energy demand oriented 21st century belongs to three additional energy sources: efficient energy use, solar energy in its many manifestations and solar hydrogen. This paper describes a new energy supply system based on renewable energy sources. The potential for reducing pollutants is described; current external environmental costs are discussed, and a strategy for the systematic development and introduction of solar technologies is proposed. The paper concludes by recalling the Energy-Environment Resolution passed in 1986 by the IAHE Board of Directors

[en] TiFe(Zr) intermetallic compound is one of the best materials for hydrogen storage which can absorb/desorb hydrogen reversibly. By means of X-ray diffraction and Moessbauer-effect, in the present paper the behaviors of the hydrogen atoms in TiFe(Zr) host lattice are investigated. According to the experimental results and theoretical calculations for Mossbauer hyperfine parameters of β-phase, it has been shown that, with respect to Mossbauer hyperfine parameters of α-phase, the contribution of volume expansion is the main effect to the change in isomer shift of β-phase, instead the contribution of valency charge is small. while the contributions of volume and valency charge are of the same importance to the change in isomer shift of γ-phase

[en] A thermochemical hydrogen production process, which is based on the GA process and features a pulse decomposition of hydrogen iodide using an iodine adsorbent (Pt/active carbon) was studied. The one-path conversion of hydrogen iodide higher than 60% could be obtained at 200 degrees C when the feed amount of hydrogen iodide per pulse was lower than 0.3 g-HI/g-adsorbent. The regeneration method of the adsorbent is discussed based on the adsorption isotherms of iodine on the active carbon. An apparatus for examining the chemical feasibility of the process was constructed. Present status of its operation is described

[en] This paper reports on the disposal of hydrogen which is often required in the operation of an experimental facility that contains hydrogen. Whether the vented hydrogen can be discharged to the atmosphere safely depends upon a number of factors, such as flow rate and atmospheric conditions. Calculations have been made that predict the distance a combustible mixture can extend from the point of release under some specified atmospheric conditions. In addition, the quantity of hydrogen in the combustible cloud is estimated. These results can be helpful in deciding whether the hydrogen can be released directly to the atmosphere or if it must be intentionally ignited

[en] This paper reports on improvement in the technique of using metal hydride in the hydrogen compression process: an industrial prototype of thermochemical hydrogen compressor. This prototype uses a fixed bed (reactor) of FeTi metallic alloy that reacts exothermically with hydrogen (absorption of the gas) at room temperature and at 10 Kgf/cm² of pressure, and desorbs the pressurized hydrogen at one specific temperature for each pressure (250 degrees C for 100 Kgf/cm²). It is presented the project, manufacture, operation, performance and a comparation with a conventional mechanical compressor working in the compression of ultra-pure hydrogen. The cost of the prototype in Brazil is also given

[en] This paper reports on pilot plant studies on hydrogen sulfide decomposition by solar energy that were carried out. The pilot plant consists of a 6-kW fix-focus type concentrator, reactor type receiver, heat exchanger, condenser, pressure swing adsorption (PSA) system for H₂/H₂S separation, and a data acquisition system. The concentrator is composed of six mirror segments mounted individually to an upper and lower carrier truss. The reactor tube (25 mm I.D. and 90 cm long) s formed into two circles and every 15 cm a type K thermocouple is inserted 6 mm deep into the catalyst bed. The reactor is connected to a shell and tube type heat exchanger followed by a sulfur condenser. Cobalt-molybdenum supported on alumina was used as a catalyst. hydrogen yields higher than 20% were obtained at a temperature of 850 degrees C using this catalyst. The produced hydrogen was separated from associate H₂S gas using the PSA system, where various molecular sieves or zeolites were tested as adsorbents. These zeolites were evaluated in terms of breakthrough time, stability, adsorption efficiency, and dynamic capacity

[en] Thermochemical water decomposition has been identified as a potentially significant future process for the production of hydrogen, which is currently an important industrial commodity, and has significant future potential as a fuel. In this paper, the thermodynamic performance of the Ispra Mark-10 thermochemical water decomposition process is investigated. Exergy analysis is used since energy analysis on its own does not pinpoint true process inefficiencies, and often does not provide rational efficiencies. The analysis has indicated that the principal losses occur in the primary water decomposition reactors, and are mainly due to internal irreversibilities associated with chemical reaction and heat transfer across large temperature differences, and that the losses associated with effluents (particularly cooling water) are not that significant

[en] In order to establish a fuel cycle of hydrogen isotopes in a D-T fusion reactor. An experimental and analytical study was carried out for the separation of a single component from a hydrogen isotopes-inert gas mixture or from a hydrogen-deuterium mixture with a vanadium particle bed. The separation was performed using a single column pressure swing absorption (PSA) process which consists of a series of three steps: pressurization step, high pressure feed step and blowdown step. The single column PSA process was found to be effective in the separation of hydrogen isotopes described in this paper, and the analytical results by means of a computer simulation could be well fitted to the experimental data

[en] The concept of a hydro-hydrogen based clean energy system is under investigation for a 100 MW scale. The goal of this paper is to prove the feasibility of the conversion of Quebec hydropower via electrolysis into hydrogen, the maritime transport of liquid hydrogen (LH₂) or methylcyclohexane (MCH) to Europe and the storage, distribution and end-use there. The end-use technologies comprise: electricity/heat cogeneration, vehicle and aviation propulsion and hydrogen enrichment of natural gas for use in industry and household. The 3 million ECU feasibility study is financed at 1/3 each, by the Commission of the European Communities, by the Quebec Government and by the numerously participating European and Canadian industry. The two year feasibility study presently is being carried out and managed by a Joint Management Group (JMG) set up by the Ludwig-Bolkow-Foundation, Germany, and Hydro-Quebec, Canada

[en] There has been a proliferation of efforts on hydride research relating to reversible hydrogen storage. Since the maximum hydrogen storage capacity available in the present day storage materials is about 3.8% (weight-wise), there is an ever ongoing search for still higher storage capacity materials. This paper reports the synthesis, characterization and hydrogenation behaviour of La-Mg (La₂Mg₁₇) hydrogen storage material. Novel features obtained are ambient condition hydrogenation-dehydrogenation characteristics of the material after the first activation (150 ± 10 degrees C; 32 kg/cm² pressure), and high storage capacity up to 6.05 weight percentage