Search

Simple, safe, scalable and low-cost method of hydrogen production via aluminum-water reaction was proposed. Hydrogen generation method is based on oxidation of coarse aluminum of centimetric scale in alkali aqueous solution with alkali concentration of no more than 0.1 M under intensive mixing of reaction medium. In presented work aluminum conversion (hydrogen yield) was studied depending on the aluminum to solution mass ratio (α changed from 30.1 to 2.7), the concentration of alkali in aqueous solution, the mixing rate, the form of aluminum particles (granules or chips) and chemical purity of aluminum. It was shown that under implemented experimental conditions alkali is continuously regenerated during oxidation reaction and synergistic effect of low content alkali aqueous solution and intensive mixing works. Aluminum conversion degree after 5 h oxidation of aluminum chips at 90 °C in 0.1 M KOH aqueous solution with α = 4 and mixing rate of 400 rpm was 75.4%. With alkali concentration increasing from 0.01 M to 0.3 M the conversion of aluminum increases from 20.7 to 95.7% (after 5 h at 90 °C, α = 4). Proposed method was strongly affected by mixing of reaction medium inside the reactor while it didn't feel the difference between aluminum chips and granules having specific surface area of 22 and 5.5 cm2/g respectively. Chemical purity of aluminum had little effect on aluminum conversion as well. Generally, proposed method can be used for hydrogen generation, aluminum waste utilization and special-grade alumina production.

Hydrogen forming by aluminium oxidation with liquid water of water solutions at low temperatures is complicated by the following reasons. Firstly, on an aluminium surface a film of oxide is formed effectively preventing further oxidation. Secondly, the rate of aluminium oxidation considerably decreases as the temperature of the system decreases. However, in this study the methods are given which enable one to overcome the above difficulties. The experiments on the oxidation of powdered activated aluminium in different water solutions have been carried out. The data obtained have been used to plot a number of curves characterizing hydrogen flow rates depending on the solution composition and the temperature of the process (the original weight of the powder was 0.25 g, solution volume - 300 ml, measuring time - 180 min). At −40 °C for KOH solution the yield of hydrogen was 50 ml, for CaCl 2 – about 5 ml, and for ZnCl 2 – approximately 2 ml. At −10 °C H 2 yield for NaOH was 264 ml, for KOH – 260 ml; at −20 °C: 100 ml for NaOH, and 225 ml for KOH. For KOH solution at temperatures of −30 °C and −40 °C the yields were equal to 192 and 49 ml respectively. Oxidation of granulated non-activated aluminium (2.5 g of aluminium per 300 ml of solution) with hydrochloric acid solution in the presence of CuCl 2 (2.5 g per 300 ml of solution) resulted in generation of more than 2000 ml of hydrogen during 300 min. For FeCl 3 solution the total value of hydrogen obtained during 180 min was equal to 70 ml, it also has been observed partial freezing of this solution.

Structural formation of plastic greases, which are essentially colloidal systems, during their fabrication and the factors that affect aging of lubricants during storage in containers and use in friction units are examined. The results of an analysis of the quality of the greases after prolonged use in friction units in different types of engineering are reported.

The higher requirements for the performance characteristics of lubricants and the intensifying competitive struggle of these products on the world market are making it necessary to assimilate new technologies which would allow deliberately altering the composition of base oils as soon as possible.

The stages and results of refining a new oil, Galol M–4042 TD, primarily intended to replace M–16IKhP–3 oil (GOST 25770) in two–stroke transport diesels, are discussed in detail in [1]. Galol M–4042 TD belongs to the SAE–40 class, i.e., it is a summer oil by definition [2]. The new oil, like M–16IKhP–3 oil, exclusively contains barium–containing additives, which is predetermined by the specific conditions of operation in two–cycle transport diesels with a high degree of boosting.

This article uses laboratory simulation to compare the oxidation rates of oils operating in electrohydraulic servo loading systems, in which the oil is in contact with atmospheric oxygen and various steels and alloys (bronze, brass, aluminium) at approximately 150 C. The oxidizability and corrosivity of the oils were rated by the quantities of oxidation products (IR spectroscopy) and dissolved iron, chromium, nickel, titanium, copper, zinc and aluminium, which are components of the alloys (by atomic absorption spectroscopy). Finds that the proposed micromethod makes it possible to shorten by a factor of 8-10 the preliminary evaluation of an oil with respect to oxidation and corrosion. Suggests that the method can be used in selecting functional additive packages, since it gives a more objective rating of oil oxidizability than do the commonly accepted test methods.

Progress in the development of a new class of materials of oil-soluble surfactants that form primary micelles is studied. AKOR10 corrosion inhibitor, as well as Sulin, developed on the basis of a mixture of petroleum and synthetic sulfonates with polarizing additives are reviewed. A detailed study is made of the influence of the adsorption/chemisorption and adhesion/cohesion properties in metal-oil-surfactant-air systems on the ability of the surfactant to reduce local contact, and pitting corrosion, corrosion in friction, corrosion fatigue, fretting wear, and fretting corrosion. The results indicate that the adsorption/chemisorption processes on the metal proceed spontaneously with a decrease in the free energy of the system, are exothermic, and promote ordering of the system.

This article reports on a study of the behavior of oil base stocks at metal/oil/air and metal/electrolyte/oil/air interfaces and the influence of the oil base stocks on the corrosion-mechanical breakdown of metals. Oil blends were formulated on the basis of data obtained previously on the preparation of synergistic formulations from liquids differing in polarity. The results indicate that the low level of protective properties of the oil base stocks, as shown by the high levels of dissolution current, makes them incapable of preventing corrosion-fatigue processes from taking place. Data on corrosion-mechanical breakdown in a metal/oil/electrolyte system show that the electrolyte aggravates the fretting corrosion of the metal in practically all of the oil base stocks that were investigated. It is concluded that the mineral and synthetic oils, while they differ in surface properties and polarity, do not protect steel against corrosionmechanical breakdown, either with or without the presence of an electrolyte.

The lube stocks from West Siberian crudes are characterized by high contents of aromatic hydrocarbons and by high viscosity indexes of the naphthenic/paraffinic and aromatic hydrocarbons. Mass spectrometric analysis showed that isoparaffins account for one-third of the total naphthenic/paraffinic hydrocarbons. The study showed that the naphthenic/paraffinic hydrocarbons of the residual lube stock from West Siberia crudes, even with a variation of molecular weight over broad limits, are relatively uniform in composition. They consist mainly of isoparaffinic and monocyclic and noncondensed naphthenic structures.

1. The action of an electric field produces an increase in the viscosity of oils, with or without polymeric additives. 2. Oil viscosity at low rates of shear is determined by structurization, and this leads to rather large errors in determining viscosity in capillary or rotating viscometers. 3. A maximum has been found in oil viscosity at certain rates of shear, as a result of static charging of the oil film. 4. Oil viscosity is affected by the surface condition of the viscometer parts and by the presence of a disperse phase. It has been shown that adsorbed surfactants can reduce oil viscosity.

1. Polar and protective properties have been studied for three oil fractions of Sosnino crude and for a distillate, raffinate, extract, and dewaxed oil from Zhirnovsk crude. It has been shown that the most polar products are those containing maximum amounts of medium and heavy aromatic hydrocarbons. 2. The polar oil products have better protective properties, owing to the formation of adsorbed films on the metal. The protection efficiency of these films is still inadequate, so that corrosion inhibitors must be added to the oils.

This paper reports on the standardization of lubricating oils and fuels used in Diesel engines in the USSR. Diesel oil users are listed along with purpose and type of Diesel engines. Grades of oil recommended for engine operation on various grades of Diesel fuel are tabulated. Standardized testing is also dealt with in this report.

In contrast to most other petroleum products, lube oils are not used up completely in the machinery or mechanism, and after a certain interval of time are drained as `used`, i.e., oil that has partially or completely lost its service qualities. In the last decade, considerable attention throughout the world has been given to the rational utilization of used petroleum products. This change has come about in part because of economic considerations (higher prices for petroleum crudes and products) and in part because of ecological considerations related to the ever-increasing pollution of the environment and increasingly stringent demands for environmental protection.

This article examines the naphthenic/paraffinic hydrocarbons segregated by liquid chromatography from a residual oil after removal of the resins and solid hydrocarbons. The studied hydrocarbons were fractionated on the basis of molecular weight (by molecular distillation) and on the basis of the content of rings (by thermal diffusion separation in a laboratory column). The results of mass-spectrometric analysis indicate that the first fraction consists mainly of isoparaffins and naphthenes with few rings. The polycyclic condensed naphthenes are concentrated in the last fraction. The content of isoparaffins drops off and the content of condensed polycyclic naphthenic structures increases from the second fraction to the next to the last. It is concluded that the naphthenic/paraffinic hydrocarbons of the residual oil from mixed West Siberian crudes have a relatively narrow composition and therefore have similar physicochemical properties.