Measurements of hydrogen solubility in various nitrobenzene-aniline mixtures were conducted in an autoclave reactor with a stirrer and control of temperature. The solubility of hydrogen was measured at 7 different values of temperature (30 °C, 40 °C, 50 °C, 90 °C, 130 °C, 170 °C, 210 °C, respectively), 3 values of stirrer rotation speed (1200 rpm, 1600 rpm, 2000 rpm, respectively) and a range of pressure of 20 ‒ 30 bar. Moreover, pure aniline, pure nitrobenzene and their mixtures with different concentrations were used. In the next step, values of Henry’s constant were calculated. Based on experimental data a dependence of Henry’s constant on temperature for pure aniline and pure nitrobenzene was proposed. Additionally, for each temperature correlations between Henry’s constant and aniline’s concentration in mixture of nitrobenzene-aniline were found.
Hydrogen-based power engineering has great potential for upgrading present and future structures of heat and electricity generation and for decarbonizing industrial technologies. The production of hydrogen and its optimal utilization in the economy and transport for the achievement of ecological and economic goals requires a wide discussion of many technological and operational – related issues as well as intensive scientific research. The introductory section of the paper indicates the main functions of hydrogen in the decarbonization of power energy generation and industrial processes, and discusses selected assumptions and conditions for the implementation of development scenarios outlined by the Hydrogen Council, 2017 and IEA, 2019. The first scenario assumes an 18% share of hydrogen in final energy consumption in 2050 and the elimination 6 Gt of carbon dioxide emissions per year. The second document was prepared in connection with the G20 summit in Japan. It presents the current state of hydrogen technology development and outlines the scenario of their development and significance, in particular until 2030. The second part of the paper presents a description of main hybrid Power-to-Power, Power-to-Gas and Power-to-Liquid technological structures with the electrolytic production of hydrogen from renewable sources. General technological diagrams of the use of water and carbon dioxide coelectrolysis in the production of fuels using F-T synthesis and the methanol production scheme are presented. Methods of integration of renewable energy with electrolytic hydrogen production technologies are indicated, and reliability indicators used in the selection of the principal modules of hybrid systems are discussed. A more detailed description is presented of the optimal method of obtaining a direct coupling of photovoltaic (PV) panels with electrolyzers.
Hydrogen as a raw material finds its main use and application on the Polish market in the chemical industry. Its potential applications for the production of energy in fuel cell systems or as a fuel for automobiles are widely analyzed and commented upon ever more frequently. At present, hydrogen is produced worldwide mainly from natural gas, using the SMR technology or via the electrolysis of water. Countries with high levels of coal resources are exceptional in that respect, as there the production of hydrogen is increasingly based on gasification processes. China is such an example. There some 68% of hydrogen is generated from coal. The paper discusses the economic efficiency of hydrogen production technologies employing lignite gasification, comparing it with steam reforming of natural gas technology (SMR). In present Polish conditions, this technology seems to be the most probable alternative for natural gas substitution.
For the purpose of evaluating the economic efficiency, a model has been developed, in which a sensitivity analysis has been carried out. An example of the technological process of energy-chemical processing of lignite has been presented, based on the gasification process rooted in disperse systems, characteristics of the fuel has been discussed, as well as carbon dioxide emission issues. Subsequently, the assumed methodology of economic assessment has been described in detail, together with its key assumptions. Successively, based on the method of discounted cash flows, the unit of hydrogen generation has been determined, which was followed by a detailed sensitivity analysis, taking the main risk factors connected with lignite/coal and natural gas price relations, as well as the price of carbon credits (allowances for emission of CO2) into account.