As many people know, the most widespread and lightest element on earth is hydrogen, while helium ranks second in our world! Helium, the second element of Mendeleev's periodic table, is an inert monatomic gas that has neither color, nor taste, nor smell. It has the lowest boiling point of all substances (-269 o C). Has 8 isotopes. Each of them is unique in its properties.
Discovery history
The discoverer of helium can rightfully be considered the French astronomer, director of the observatory in Meudon, Pierre Jules César Jansen. In 1868, while studying the sun, namely the chromosphere, an astronomer captured a line of bright yellow color, which was initially and mistakenly attributed to the spectrum of sodium. But, a few years later, in 1871, Pierre, together with the English astronomer Joseph Lockyer, found that the line found by Janssen did not belong to any of the chemical elements known at that time. The name helium got from the word "helios", which translated from Greek means - the sun! First of all, scientists suggested that the found element is a metal, but nowadays, we can say with confidence that it was a false assumption.
As many people know, absolutely all gases can be brought into a liquid state, but this, of course, will require certain conditions. Liquefied was opened only in 1908. The Dutch physicist Heike Kamerling Onnes lowered the pressure of the gas flowing through the throttle, having previously cooled the helium.
Solid helium was obtained only 20 years later in 1926. A student of Kamerlingh Onnes, he was able to achieve gas crystals by increasing the helium pressure above 35 atmospheres and cooling the gas to an extremely low temperature.
Let's start with the fact that helium cannot enter into chemical reactions at all, and also has no oxidation states. Helium is a monatomic gas, and has only one electronic level (shell), being an extremely stable gas, since it has the first level completely filled with electrons, which indicates a strong effect of the nucleus on the electrons. Helium atoms, not that they do not react with other substances, moreover, they do not even combine with each other.
Liquid helium has a number of absolutely unique properties. In the 30s of the 20th century, at even lower temperatures, an extremely strange and incredible phenomenon was noticed - when helium is cooled to a temperature of only 2 degrees above absolute zero, its unexpected transformation occurs. The surface of the liquid becomes absolutely calm and smooth, not a single bubble, not the slightest bubbling of liquid. Liquid helium turns into a superfluid liquid. Such helium can climb up the walls and "escape" from the vessel in which it is stored, this is due to the zero viscosity of the liquefied gas. It can become a zero-friction fountain, which means it can flow indefinitely. Despite all the theories, scientists have established that liquefied helium is not an easy liquid. For example, starting with 2He, it turned out that liquefied gas consists of two interpenetrating liquids: normal (viscous) and superfluid (zero viscosity) components. The superfluid component is ideal and has zero friction when flowing in any vessel and capillary.
As for solid helium, at the moment, scientists are conducting numerous experiments and experiments. Solid 4He has a quantum effect such as a crystallization wave. This effect is based on the oscillation of the phase boundary in the "crystal - liquid" system. It is enough to shake such helium a little, and the phase boundary between liquid and solid will be similar to the boundary of two liquids!
Industrial use of helium
Basically, helium is needed to obtain extremely low temperatures, as well as in metallurgy for smelting pure metals. Also 2He is not only one of the best heat transfer fluids, but also a good propellant (E939) in the food industry.
With the help of helium, it is possible to determine the location of faults in the thickness of the Earth, since it is released during the decay of radioactive elements that are saturated with the earth's crust. The concentration of helium at the exit from the crack is 50-100 times higher than normal.
Moreover, aircraft such as airships are filled with helium. Helium is much lighter than air, so the lifting force of such vessels is very high. Yes, hydrogen is lighter than helium. So why not use it? Hydrogen is a combustible element, and it is extremely dangerous to refuel airships with it.
Danger
Any excess gas concentration can be hazardous to human health. Inhalation of high concentration of helium air can cause unconsciousness, severe vomiting, and even death. Death occurs as a result of oxygen starvation due to the fact that it does not enter the lungs
Helium is a truly noble gas. It has not yet been possible to force him to enter into any reactions. The helium molecule is monoatomic. In lightness, this gas is second only to hydrogen, air is 7.25 times heavier than helium. Helium is almost insoluble in water and other liquids. And in the same way, not a single substance dissolves noticeably in liquid helium.
Solid helium cannot be produced at any temperature unless the pressure is increased.
In the history of the discovery, research and application of this element, there are the names of many prominent physicists and chemists from different countries. They were interested in helium, they worked with helium: Jansen (France), Lockyer, Ramsay, Crooks, Rutherford (England), Palmieri (Italy), Keesom, Kamerling-Onnes (Holland), Feynman, Onsager (USA), Kapitsa, Kikoin, Landau ( Soviet Union) and many other prominent scientists.
The uniqueness of the appearance of the helium atom is determined by the combination of two amazing natural structures in it - absolute champions in compactness and strength. In the nucleus of helium, helium-4, both intranuclear shells are saturated - both proton and neutron. The electronic doublet that surrounds this nucleus is also saturated. These constructions hold the key to understanding the properties of helium. This is the source of its phenomenal chemical inertness and record-breaking small size of its atom.
The role of the nucleus of the helium atom - an alpha particle - is enormous in the history of the formation and development of nuclear physics. If you remember, it was the study of alpha particle scattering that led Rutherford to the discovery of the atomic nucleus. During the bombardment of nitrogen with alpha particles, the interconversion of elements was first carried out - something that many generations of alchemists dreamed of for centuries. True, in this reaction, not mercury turned into gold, but nitrogen into oxygen, but this is almost as difficult to do. The same alpha particles were involved in the discovery of the neutron and the production of the first artificial isotope. Later, with the help of alpha particles, curium, berkelium, californium, mendelevium were synthesized.
We have listed these facts with only one purpose - to show that element number 2 is a very unusual element.
Terrestrial helium
Helium is an unusual element, and its history is unusual... It was discovered in the atmosphere of the Sun 13 years earlier than on Earth. More precisely, a bright yellow line D was discovered in the spectrum of the solar corona, and what was hidden behind it became reliably known only after helium was extracted from terrestrial minerals containing radioactive elements.
In the earth's crust, there are 29 isotopes, the radioactive decay of which produces alpha particles - highly active, high-energy helium nuclei.
Basically, terrestrial helium is formed during the radioactive decay of uranium-238, uranium-235, thorium and their unstable decay products. Incomparably smaller amounts of helium are produced by the slow decay of samarium-147 and bismuth. All these elements generate only the heavy isotope of helium - 4 He, whose atoms can be regarded as the remains of alpha particles buried in a shell of two paired electrons - in an electronic doublet. In the early geological periods, there probably existed other naturally radioactive series of elements that had already disappeared from the face of the Earth, saturating the planet with helium. One of them was the now artificially recreated neptunium row.
By the amount of helium trapped in a rock or mineral, one can judge their absolute age. These measurements are based on the laws of radioactive decay: for example, half of uranium-238 in 4.52 billion years turns into heliumand lead.
Helium accumulates in the earth's crust slowly. One ton of granite, containing 2 g of uranium and 10 g of thorium, produces only 0.09 mg of helium in a million years - half a cubic centimeter. In very few minerals rich in uranium and thorium, the helium content is quite high - several cubic centimeters of helium per gram. However, the proportion of these minerals in natural helium production is close to zero, as they are very rare.
Helium pi The sun was discovered by the Frenchman J. Jansen, who conducted his observations in India on August 10, 1868, and the Englishman J. Lockyer, on October 20 of the same year. The letters of both scientists arrived in Paris on the same day and were read at a meeting of the Paris Academy of Sciences on October 26 at intervals of several minutes. The academicians, amazed at such a strange coincidence, adopted a resolution to knock out a gold medal in honor of this event.
Natural compounds, which contain alpha-active isotopes, are only a primary source, but not a raw material for the industrial production of helium. True, some minerals with a dense structure - native metals, magnetite, garnet, apatite, zircon and others - firmly hold the helium contained in them. However, over time, most minerals undergo processes of weathering, recrystallization, etc., and helium leaves them.
The helium bubbles released from the crystal structures are sent on a journey across the earth's crust. A very small part of them dissolves in groundwater. For the formation of more or less concentrated helium solutions, special conditions are required, above all high pressures. Another part of the wandering helium is released through the pores and cracks of the minerals into the atmosphere. The rest of the gas molecules fall into underground traps, in which they accumulate for tens, hundreds of millions of years. The traps are layers of loose rocks, the voids of which are filled with gas. The bed for such gas reservoirs is usually water and oil, and from above they are blocked by gas-tight strata of dense rocks.
Since other gases (mainly methane, nitrogen, carbon dioxide) wander in the earth's crust, and, moreover, in much larger quantities, then purely helium accumulations do not exist. Helium is present in natural gases as a minor impurity. Its content does not exceed thousandths, hundredths, rarely tenths of a percent. The large (1.5-10%) helium content of methane-nitrogen deposits is an extremely rare phenomenon.
Natural gases turned out to be practically the only source of raw materials for the industrial production of helium. For separation from other gases, the exceptional volatility of helium is used, associated with its low liquefaction temperature. After all other components of the natural gas have been condensed by deep cooling, the helium gas is evacuated. Then it is cleaned of impurities. The purity of factory helium reaches 99.995%.
Helium reserves on Earth are estimated at 54014 m 3; judging by the calculations, it was formed in the earth's crust for 2 billion years in tens of times more. This discrepancy between theory and practice is understandable. Helium is a light gas and, like hydrogen (albeit slower), it escapes from the atmosphere into space. Probably, during the existence of the Earth, the helium of our planet was repeatedly renewed - the old one evaporated into space, and instead of it the fresh one “exhaled” by the Earth entered the atmosphere.
In the lithosphere, helium is at least 200 thousand times more than in the atmosphere; even more potential helium is stored in the "womb" of the earth - in alpha-active elements. But the total content of this element in the Earth and the atmosphere is small. Helium is a rare and scattered gas. 1 kg of terrestrial material accounts for only 0.003 mg of helium, and its content in the air is 0.00052 volume percent. Such a low concentration does not yet allow economically extracting helium from the air.
Inert but much needed helium
At the end of the last century, the English magazine "Punch" published a caricature in which helium was depicted as a sly winking little man - an inhabitant of the Sun. The text under the picture read: “Finally I have been caught on Earth! It lasted long enough! I wonder how long it will take until they figure out what to do with me? "
Indeed, 34 years have passed since the discovery of terrestrial helium (the first report on this was published in 1881) before it found practical application. A certain role was played here by the original physicotechnical, electrical and, to a lesser extent, the chemical properties of helium, which required a long study. The main obstacles were the absent-mindedness and high cost of element No. 2. Therefore, helium was not available to practice.
The Germans were the first to use helium. In 1915 they began to fill their airships bombing London with it. Soon, light, but non-combustible helium became an indispensable filler for aeronautics. The decline in airship construction, which began in the mid-30s, led to a certain decline in the production of helium, but only for a short time. This gas increasingly attracted the attention of chemists, metallurgists and machine builders.
Many technological processes and operations cannot be carried out in air. To avoid the interaction of the resulting substance (or feedstock) with air gases, create special protective environments; and there is no gas more suitable for these purposes than helium.
Inert, lightweight, mobile, well-conductive heat, helium is an ideal tool for squeezing flammable liquids and powders from one container to another; it is these functions that he performs in missiles and guided missiles. Separate stages of nuclear fuel production take place in a helium protective environment. Fuel elements of nuclear reactors are stored and transported in containers filled with helium. With the help of special leak detectors, the action of which is based on the exceptional diffusion capacity of helium, they reveal the slightest possibility of leakage in nuclear reactors or other systems under pressure or vacuum.
The last years have been marked by the repeated rise of airship building, now on a higher scientific and technical basis. In a number of countries, airships with helium filling with a carrying capacity of 100 to 3000 tons have been built and are being built. They are economical, reliable and convenient for the transportation of bulky cargo, such as gas pipelines, oil refineries, power line supports, etc. Filling of 85% helium and 15% hydrogen is fire safe and only 7% less lift compared to hydrogen filling.
High-temperature nuclear reactors of a new type, in which helium serves as a coolant, began to operate.
Liquid helium is widely used in scientific research and technology. Ultra-low temperatures favor in-depth knowledge of matter and its structure - at higher temperatures, the fine details of the energy spectra are masked by the thermal motion of atoms.
There are already superconducting solenoids made of special alloys that create strong magnetic fields (up to 300 thousand oersteds) at the temperature of liquid helium at negligible energy costs.
At the temperature of liquid helium, many metals and alloys become superconductors. Superconducting relays - cryotrons are increasingly used in the designs of electronic computers. They are simple, reliable, very compact. Superconductors, and with them liquid helium, are becoming essential for electronics. They are included in the design of infrared detectors, molecular amplifiers (masers), optical quantum generators (lasers), and devices for measuring ultrahigh frequencies.
Of course, these examples do not exhaust the role of helium in modern technology. But if not for the limited natural resources, not for the extreme absent-mindedness of helium, he would find many more applications. It is known, for example, that food products retain their original taste and aroma when preserved in a helium environment. But "helium" canned food still remains a "thing in itself", because helium is not enough and it is used only in the most important industries and where one cannot do without it. Therefore, it is especially offensive to realize that much larger amounts of helium pass and leave into the atmosphere with combustible natural gas through chemical synthesis apparatus, furnaces and furnaces than those that are extracted from helium sources.
It is now considered beneficial to release helium only if its content in natural gas is not less than 0.05%. The reserves of such gas are constantly decreasing, and it is possible that they will be exhausted before the end of our century. However, the problem of "helium deficiency" by this time is likely to be solved - partly due to the creation of new, more advanced methods for separating gases, extracting from them the most valuable, albeit insignificant, fractions, and partly due to controlled thermonuclear fusion. Helium will become an important, albeit byproduct, of artificial suns.
HELIUM ISOTOPES.There are two stable helium isotopes in nature: helium-3 and helium-4. A light isotope is a million times less abundant on Earth than a heavy one. It is the rarest stable isotope on our planet. Three more isotopes of helium were obtained by artificial means. They are all radioactive. The half-life of helium-5 is 2.440-21 seconds, helium-6 is 0.83 seconds, and helium-8 is 0.18 seconds. The heaviest isotope, interesting in that there are three neutrons per proton in its nuclei, was first obtained in Dubna in the 60s. Attempts to obtain helium-10 have so far been unsuccessful.
LAST SOLID GAS. In the liquid and solid state, helium was converted by the very last of all gases. The particular difficulties in liquefying and solidifying helium are explained by the structure of its atom and some peculiarities of its physical properties. In particular, helium, like hydrogen, at temperatures above - 250 ° C, while expanding, does not cool down, but heats up. On the other hand, the critical temperature of helium is extremely low. That is why liquid helium was first obtained only in 1908, and solid - in 1926.
HELIUM AIR. Air, in which all or most of the nitrogen has been replaced by helium, is no longer news today. It is widely used on land, underground and underwater.
Helium air is three times lighter and much more mobile than ordinary air. It behaves more actively in the lungs - it quickly supplies oxygen and quickly evacuates carbon dioxide. That is why helium air is given to patients with respiratory disorders and some operations. It relieves suffocation, treats bronchial asthma and diseases of the larynx.
Breathing in helium air practically eliminates nitrogen embolism (decompression sickness), which, during the transition from high pressure to normal, affects divers and specialists of other professions, whose work takes place under conditions of high pressure. The cause of this disease is quite significant, especially with increased pressure, the solubility of nitrogen in the blood. As the pressure decreases, it is released in the form of gas bubbles, which can clog blood vessels, damage nerve nodes ... Unlike nitrogen, helium is practically insoluble in body fluids, so it cannot cause decompression sickness. In addition, helium air excludes the occurrence of "nitrogen narcosis", which looks similar to alcohol intoxication.
Sooner or later, mankind will have to learn to live and work on the seabed for a long time in order to take advantage of the mineral and food resources of the shelf. And at great depths, as the experiments of Soviet, French and American researchers have shown, helium air is still irreplaceable. Biologists have proved that prolonged breathing with helium air does not cause negative changes in the human body and does not threaten changes in the genetic apparatus: the helium atmosphere does not affect the development of cells and the frequency of mutations. There are known works, the authors of which consider helium air to be the optimal air environment for spacecraft making long flights into the Universe.
OUR HELIUM. In 1980, a group of scientists and specialists headed by I. L. Andreev was awarded the State Prize for the creation and implementation of the technology for producing helium concentrates from relatively poor helium gases. A helium plant has been built at the Orenburg gas field, which has become our main supplier of "solar gas" for the needs of various industries.
HELIUM COMPLEX. In 1978, Academician V.A.Legasov and his colleagues during the decay of tritium nuclei included in the glycine amino acid molecule managed to register a paramagnetic helium-containing complex, in which hyperfine interaction of a helium-3 nucleus with an unpaired electron was observed. This is the greatest achievement in helium chemistry so far.
Helium (He) - inert gas, which is the second element of the periodic table of elements, as well as the second element in terms of lightness and prevalence in the Universe. It belongs to simple substances and under standard conditions (Standard temperature and pressure) is a monoatomic gas.
Helium has no taste, color, odor and does not contain toxins.
Among all simple substances, helium has the lowest boiling point (T \u003d 4.216 K). It is impossible to obtain solid helium at atmospheric pressure, even at temperatures close to absolute zero - for the transition to a solid form, helium needs a pressure above 25 atmospheres. There are few chemical compounds of helium and all of them are unstable under standard conditions.
Naturally occurring helium is composed of two stable isotopes, He and 4He. Isotope "He" is very rare (isotopic abundance 0.00014%) at 99.99986% for isotope 4He. In addition to natural, 6 artificial radioactive isotopes of helium are also known.
The appearance of practically everything in the Universe, helium, was the primary nucleosynthesis that took place in the first minutes after the Big Bang.
Currently, almost all helium is formed from hydrogen as a result of thermonuclear fusion that occurs in the bowels of stars. On our planet, helium is formed during the alpha decay of heavy elements. That part of helium, which manages to seep through the Earth's crust, comes out as part of natural gas and can be up to 7% of its composition. To highlight helium from natural gas, fractional distillation is used - a process of low-temperature separation of elements.
History of the discovery of helium
A total solar eclipse was expected on 18 August 1868. Astronomers around the world have been actively preparing for this day. They hoped to solve the mystery of prominences - luminous protrusions visible at the time of a total solar eclipse at the edges of the solar disk. Some astronomers believed that the prominences are high lunar mountains, which at the time of a total solar eclipse are illuminated by the rays of the Sun; others thought the prominences were mountains on the sun itself; still others saw fiery clouds of the solar atmosphere in the solar projections. The majority, however, believed that prominences were nothing more than an optical illusion.
In 1851, during a solar eclipse observed in Europe, the German astronomer Schmidt not only saw the solar protrusions, but also managed to see that their outlines were changing over time. Based on his observations, Schmidt concluded that prominences are incandescent gas clouds ejected into the solar atmosphere by giant eruptions. However, even after Schmidt's observations, many astronomers still considered the fiery protrusions to be an illusion.
Only after the total eclipse of July 18, 1860, which was observed in Spain, when many astronomers saw the solar protrusions with their own eyes, and the Italian Secchi and the Frenchman Dellar managed not only to sketch, but also to photograph them, no one doubted the existence of prominences. ...
By 1860, a spectroscope had already been invented - a device that makes it possible, by observing the visible part of the optical spectrum, to determine the qualitative composition of the body from which the observed spectrum is obtained. However, on the day of the solar eclipse, none of the astronomers used a spectroscope to examine the spectrum of prominences. They remembered about the spectroscope when the eclipse had already ended.
That is why, in preparation for the solar eclipse of 1868, every astronomer included a spectroscope in the list of instruments for observation. Jules Jansen, a famous French scientist, did not forget this device when he set out to observe prominences in India, where the conditions for observing a solar eclipse, according to astronomers' calculations, were the best.
At the moment when the sparkling disk of the Sun was completely covered by the Moon, Jules Jansen, examining the orange-red flames escaping from the surface of the Sun with a spectroscope, saw in the spectrum, in addition to three familiar hydrogen lines: red, green-blue and blue, a new one, unfamiliar - bright yellow. None of the substances known to chemists of that time had such a line in the part of the spectrum where it was discovered by Jules Jansen. The same discovery, but at home in England, was made by the astronomer Norman Lockyer.
On October 25, 1868, the Paris Academy of Sciences received two letters. One, written the day after the solar eclipse, came from Guntur, a small town on the east coast of India, from Jules Jansen; another letter, dated October 20, 1868, was from England from Norman Lockyer.
The letters received were read out at a meeting of the professors of the Paris Academy of Sciences. In them, Jules Janssen and Norman Lockyer, independently of one another, reported the discovery of the same "solar matter". This new substance, found on the surface of the Sun using a spectroscope, Lokier proposed to call helium from the Greek word for "sun" - "helios".
This coincidence surprised the scientific meeting of professors of the Academies and at the same time testified to the objective nature of the discovery of a new chemical substance. A medal was struck in honor of the discovery of the substance of solar torches (prominences). On one side of this medal are embossed portraits of Jansen and Lockyer, and on the other - the image of the ancient Greek sun god Apollo in a chariot drawn by four horses. Under the chariot was an inscription in French: "Analysis of the solar ledges August 18, 1868"
In 1895, the London chemist Henry Myers drew the attention of William Ramsay, the famous English physicist and chemist, to the then forgotten article by the geologist Hildebrand. In this article, Hildebrand argued that some rare minerals, when heated in sulfuric acid, release a gas that does not burn and does not support combustion. Among these rare minerals was kleveite, found in Norway by Nordenskjöld, the famous Swedish explorer of the polar regions.
Ramsay decided to investigate the nature of the gas contained in the cloveite. In all chemical stores in London, Ramsay's assistants managed to buy only ... one gram of cloveite, paying only 3.5 shillings for it. Having isolated several cubic centimeters of gas from the obtained amount of cleveite and purified it from impurities, Ramsay examined it using a spectroscope. The result was unexpected: the gas released from the cloveite turned out to be ... helium!
Not trusting his discovery, Ramsay turned to William Crookes, the largest specialist in spectral analysis in London at the time, with a request to investigate the gas released from the cloveite.
Crookes investigated the gas. The result of the study confirmed the discovery of Ramsay. So on March 23, 1895, a substance was discovered on Earth that was found on the Sun 27 years ago. On the same day, Ramsay published his discovery, sending one message to the Royal Society of London, and another to the famous French chemist, Academician Berthelot. In a letter to Berthelot, Ramsay asked to inform the scientific meeting of professors of the Paris Academy about his discovery.
15 days after Ramsay, independently of him, the Swedish chemist Langle isolated helium from cleveite and, like Ramsay, reported his discovery of helium to the chemist Berthelot.
For the third time, helium was discovered in the air, where, according to Ramsay, he had to come from rare minerals (cleveite, etc.) during destruction and chemical transformations on Earth.
Small amounts of helium were also found in the water of some mineral springs. So, for example, it was found by Ramsay in the curative spring of Cautere in the Pyrenees, the English physicist John William Rayleigh found it in the waters of the springs at the famous resort of Bath, the German physicist Kaiser discovered helium in the springs gushing in the Black Forest mountains. However, helium has been found most of all in some minerals. It is found in samarskite, fergusonite, columbite, monazite, uranite. The mineral thorianite from the island of Ceylon contains a particularly high amount of helium. A kilogram of thorianite, when heated red-hot, releases 10 liters of helium.
It was soon established that helium is found only in those minerals that contain radioactive uranium and thorium. The alpha rays emitted by some radioactive elements are nothing more than the nuclei of helium atoms.
From the history...
Its unusual properties allow helium to be widely used for a variety of purposes. The first, absolutely logical, based on its lightness, is the use in balloons and airships. Moreover, unlike hydrogen, it is not explosive. This property of helium was used by the Germans in the First World War in combat airships. The downside of using it is that an airship filled with helium will not fly as high as a hydrogen one.
To bombard large cities, mainly the capitals of England and France, the German command used airships (zeppelins) in the First World War. Hydrogen was used to fill them. Therefore, the fight against them was relatively simple: an incendiary projectile that fell into the shell of the airship set fire to hydrogen, which instantly flared up and the device burned out. Of the 123 airships built in Germany during the First World War, 40 burned down from incendiary shells. But one day the General Staff of the British Army was surprised by a message of particular importance. Direct hits of incendiary shells in the German zeppelin did not give results. The airship did not flare up, but slowly flowing out with some unknown gas, flew back.
Military experts were perplexed and, despite an urgent and detailed discussion of the issue of the non-flammability of zeppelin from incendiary shells, they could not find the necessary explanation. The riddle was solved by the English chemist Richard Threlfall. In a letter to the British Admiralty, he wrote: "... I believe that the Germans have invented some way to extract helium in large quantities, and this time they filled the shell of their zeppelin not with hydrogen, as usual, but with helium ..."
The persuasiveness of Threlfall's arguments, however, was diminished by the fact that there were no significant sources of helium in Germany. True, helium is contained in the air, but there is little of it: one cubic meter of air contains only 5 cubic centimeters of helium. The Linde system chiller, which converts several hundred cubic meters of air into liquid in one hour, could produce no more than 3 liters of helium during this time.
3 liters of helium per hour! And to fill the zeppelin, you need 5 ÷ 6 thousand cubic meters. m. To obtain such an amount of helium, one Linde machine had to work without stopping for about two hundred years, two hundred such machines would give the required amount of helium in one year. The construction of 200 factories for converting air into liquid to obtain helium is economically very unprofitable, and practically pointless.
Where did German chemists get helium from?
This question, as it turned out later, was solved in a relatively simple way. Long before the war, German shipping companies that transported goods to India and Brazil were instructed to load returning ships not with ordinary ballast, but with monazite sand, which contains helium. Thus, a reserve of "helium raw materials" was created - about 5 thousand tons of monazite sand, from which helium was obtained for zeppelin. In addition, helium was extracted from the water of the Nauheim mineral spring, which produced up to 70 cubic meters. m of helium daily.
The case with the fireproof zeppelin was the impetus for a new search for helium. Chemists, physicists and geologists began to search for helium. It has suddenly acquired tremendous value. In 1916, 1 cubic meter of helium cost 200,000 rubles in gold, that is, 200 rubles per liter. Considering that a liter of helium weighs 0.18 g, then 1 g cost over 1,000 rubles.
Helium became an object of hunting for merchants, speculators, stock dealers. Helium was found in significant quantities in natural gases coming out of the bowels of the earth in America, in the state of Kansas, where, after America entered the war, a helium plant was built near Fort Worth. But the war ended, the reserves of helium remained unused, the cost of helium fell sharply and at the end of 1918 was about four rubles per cubic meter.
Helium extracted with such difficulty was used by the Americans only in 1923 to fill the now peaceful Shenandoah airship. It was the world's first and only air cargo-passenger ship filled with helium. However, his "life" was short-lived. Two years after its birth, "Shenandoah" was destroyed by a storm. 55 thousand cubic meters m, almost the entire world stock of helium, collected over six years, disappeared without a trace in the atmosphere during a storm that lasted only 30 minutes.
Helium application
Helium in nature
Mostly terrestrial helium formed during the radioactive decay of uranium-238, uranium-235, thorium and their unstable decay products. Incomparably smaller amounts of helium are produced by the slow decay of samarium-147 and bismuth. All these elements generate only a heavy isotope of helium - He 4, whose atoms can be considered as the remains of alpha particles buried in a shell of two paired electrons - in an electronic doublet. In the early geological periods, there probably existed other naturally radioactive series of elements that had already disappeared from the face of the Earth, saturating the planet with helium. One of them was the now artificially recreated neptunium row.
By the amount of helium trapped in a rock or mineral, one can judge their absolute age. These measurements are based on the laws of radioactive decay: for example, half of uranium-238 in 4.52 billion years turns into helium and lead.
Helium slowly accumulates in the earth's crust. One ton of granite, containing 2 g of uranium and 10 g of thorium, produces only 0.09 mg of helium in a million years - half a cubic centimeter. In very few minerals rich in uranium and thorium, the helium content is quite high - a few cubic centimeters of helium per gram. However, the share of these minerals in natural helium production is close to zero, as they are very rare.
On Earth, helium is small: 1 m 3 of air contains only 5.24 cm 3 of helium, and each kilogram of terrestrial material contains 0.003 mg of helium. But in terms of prevalence in the Universe, helium ranks second after hydrogen: helium accounts for about 23% of the cosmic mass. About half of all helium is concentrated in the earth's crust, mainly in its granite shell, which has accumulated the main reserves of radioactive elements. The content of helium in the earth's crust is small - 3 x 10 -7% by mass. Helium accumulates in free gas accumulations of bowels and in oils; such deposits reach industrial proportions. The maximum concentrations of helium (10-13%) were found in free gas accumulations and gases of uranium mines and (20-25%) in gases spontaneously released from groundwater. The older the age of gas-bearing sedimentary rocks and the higher the content of radioactive elements in them, the more helium is in the composition of natural gases.
Extraction of helium
Extraction of helium on an industrial scale is made from natural and petroleum gases of both hydrocarbon and nitrogen composition. According to the quality of raw materials, helium deposits are subdivided into: rich (He content\u003e 0.5% by volume); privates (0.10-0.50) and the poor< 0,10). Значительные его концентрации известны в некоторых месторождениях природного газа Канады, США (шт. Канзас, Техас, Нью-Мексико, Юта).
The world reserves of helium are 45.6 billion cubic meters. Large deposits are located in the United States (45% of world resources), followed by Russia (32%), Algeria (7%), Canada (7%) and China (4%).
The USA is also in the lead in helium production (140 million cubic meters per year), followed by Algeria (16 million).
Russia ranks third in the world - 6 million cubic meters per year. The Orenburg Helium Plant is currently the only domestic source of helium production, and gas production is declining. In this regard, gas fields in Eastern Siberia and the Far East with high concentrations of helium (up to 0.6%) are of particular importance. One of the most promising is the Kovykta ha zocondensate field located in the north of the Irkutsk region. According to experts, it contains about 25% of the world'sx helium reserves.
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Helium (grade A) (according to TU 51-940-80) |
Helium (grade B) (according to TU 51-940-80) |
High purity helium, grade 5.5 (according to TU 0271-001-45905715-02) |
Helium of high purity, grade 6.0 (according to TU 0271-001-45905715-02) |
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Helium, not less |
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Nitrogen, no more |
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Oxygen + argon |
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Neon, no more |
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Water vapor, no more |
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Hydrocarbons, no more |
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CO2 + CO, no more |
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Hydrogen, no more |
Safety
- Helium is not toxic, not flammable, not explosive
- Helium is allowed to be used in any places of mass gathering of people: at concerts, promotions, stadiums, shops.
- Gaseous helium is physiologically inert and does not pose a danger to humans.
- Helium is not dangerous for the environment, therefore, it is not required to neutralize, utilize and eliminate its residues in cylinders.
- Helium is much lighter than air and dissipates in the upper layers of the Earth's atmosphere.
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Helium (grades A and B according to TU 51-940-80) |
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Technical name |
Helium gaseous |
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Chemical formula |
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OON number |
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Transport hazard class |
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Physical properties |
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Physical state |
Under normal conditions - gas |
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Density, kg / m³ |
Under normal conditions (101.3 kPa, 20 C), 1627 |
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Boiling point, C at 101.3 kPa |
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Temperature of the 3rd point and its equilibrium pressure С, (mPa) |
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Water solubility |
insignificant |
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Fire and explosion hazard |
fire and explosion proof |
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Stability and reactivity |
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Stability |
Stable |
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Reactivity |
Inert gas |
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Danger to humans |
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Toxic effects |
Non toxic |
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Environmental hazard |
Does not have a harmful effect on the environment |
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Facilities |
Any means are applicable |
Storage and transportation of helium
Gaseous helium can be transported by all types of transport in accordance with the rules for the carriage of goods by a particular mode of transport. Transportation is carried out in special brown steel cylinders and containers for the transport of helium. Liquid helium is transported in transport vessels such as STG-40, STG-10 and STG-25 with a volume of 40, 10 and 25 liters.
Rules for the carriage of cylinders with technical gases
The transportation of dangerous goods in the Russian Federation is regulated by the following documents:
1. "Regulations for the carriage of dangerous goods by road" (as amended by the Orders of the Ministry of Transport of the Russian Federation of 11.06.1999 No. 37, of 14.10.1999 No. 77; registered with the Ministry of Justice of the Russian Federation on December 18, 1995, registration No. 997).
2. "European Agreement on the International Carriage of Dangerous Goods by Road" (ADR), to which Russia officially joined on April 28, 1994 (Decree of the Government of the Russian Federation of 03.02.1994 No. 76).
3. "Rules of the road" (SDA 2006), namely article 23.5, which states that "The carriage of ... dangerous goods ... is carried out in accordance with special rules."
4. "Code of the Russian Federation on Administrative Offenses", article 12.21, part 2 of which provides for liability for violation of the rules for the transportation of dangerous goods in the form of "an administrative fine for drivers in the amount of one to three times the minimum wage or deprivation of the right to drive vehicles for a period of one to three months; for officials responsible for transportation - from ten to twenty times the minimum wage. "
In accordance with clause 3, clause 1.2 "The Rules do not apply to ... the carriage of a limited amount of dangerous substances in one vehicle, the carriage of which can be considered as the carriage of non-dangerous goods." It also explains that "A limited amount of dangerous goods is determined in the requirements for the safe transportation of a specific type of dangerous goods. When determining it, it is possible to use the requirements of the European Agreement on the International Carriage of Dangerous Goods (ADR)." Thus, the question of the maximum amount of substances that can be transported as a non-hazardous cargo is reduced to the study of section 1.1.3 of ADR, which establishes exemptions from the European regulations for the carriage of dangerous goods associated with various circumstances.
So, for example, in accordance with paragraph 1.1.3.1 "The provisions of ADR do not apply ... to the carriage of dangerous goods by individuals, when these goods are packed for retail sale and are intended for their personal consumption, use in everyday life, leisure or sports, when provided that measures are taken to prevent any leakage of the contents under normal conditions of carriage. "
However, a group of exemptions formally recognized by the rules for the carriage of dangerous goods are exemptions associated with quantities transported in one transport unit (clause 1.1.3.6).
All gases are classified in the second class of substances according to the ADR classification. Non-flammable, non-toxic gases (groups A - neutral and O - oxidizing) belong to the third transport category, with a maximum amount limited to 1000 units. Flammable (group F) - to the second, with a maximum quantity limit of 333 units. By "unit" is meant here 1 liter of the capacity of the vessel containing the compressed gas, or 1 kg of liquefied or dissolved gas. Thus, the maximum amount of gases that can be transported in one transport unit as non-hazardous cargo is as follows:
The chemical element helium was first discovered on the Sun and only then on Earth.
A key role in the history of the discovery of helium was played by Norman Lockyer, the founder of one of the world's leading scientific publications - the journal Nature... In preparation for the publication of the magazine, he became acquainted with the London scientific establishment and became interested in astronomy. This was the time when, inspired by the Kirchhoff-Bunsen discovery, astronomers were just beginning to study the spectrum of light emitted by stars. Lockyer himself managed to make a number of important discoveries - in particular, he was the first to show that sunspots are colder than the rest of the solar surface, and also the first to indicate the presence of an outer shell in the Sun, calling it chromosphere... In 1868, while examining the light emitted by atoms in prominences - huge ejections of plasma from the sun's surface - Lockyer noticed a number of previously unknown spectral lines ( cm. Spectroscopy). Attempts to obtain the same lines in laboratory conditions ended in failure, from which Lockyer concluded that he had discovered a new chemical element. Lockyer named it helium, from the Greek helios - "The sun".
Scientists wondered how they should react to the appearance of helium. Some suggested that a mistake was made in interpreting the spectra of prominences, but this point of view received fewer and fewer supporters, as more and more astronomers were able to observe the Lockyer lines. Others argued that there are elements on the Sun that are not on Earth - which, as already mentioned, contradicts the main point about the laws of nature. Still others (they were in the minority) believed that someday helium would be found on Earth as well.
In the late 1890s, Lord Rayleigh and Sir William Ramsay conducted a series of experiments that led to the discovery of argon. Ramsay redesigned his setup to study the gases emitted by uranium-containing minerals. Ramsay found unknown lines in the spectrum of these gases and sent samples to several colleagues for analysis. Upon receiving the sample, Lockyer immediately recognized the lines that he had observed in sunlight over a quarter of a century ago. The riddle of helium has been solved: the gas is undoubtedly in the sun, but it also exists here on Earth. Nowadays, this gas is best known in ordinary life as a gas for inflating airships and balloons ( cm. Graham's law), and in science - thanks to its application in cryogenics, technologies for achieving ultra-low temperatures.
Coronium and Nebulium
The question of whether there are chemical elements anywhere in the Universe that are not on Earth has not lost its relevance in the 20th century. When studying the outer solar atmosphere - the solar crowns, consisting of a hot, highly rarefied plasma - astronomers have discovered spectral lines that they could not identify with any of the known earthly elements. Scientists have suggested that these lines belong to a new element, which was named corona... And when studying the spectra of some nebulae - distant accumulations of gases and dust in the Galaxy - more mysterious lines were discovered. They were assigned to another "new" element - nebulia... In the 1930s, the American astrophysicist Ira Sprague Bowen (1898-1973) came to the conclusion that the nebulium lines actually belong to oxygen, but acquired this form due to the extreme conditions existing on the Sun and in nebulae, and these conditions cannot be reproduced in terrestrial laboratories. Coronium turned out to be highly ionized iron. And these lines were named forbidden lines.
Joseph Norman LOKIER
Joseph Norman Lockyer, 1836-1920
English scientist. Born in the city of Rugby in the family of a military doctor. Lockyer entered science in an unusual way, starting his career as an official in the Ministry of War. To earn some money, he took advantage of the public interest in science to publish a popular science magazine. The first issue of the magazine was published in 1869 Natureand Lockyer remained its editor for 50 years. He has participated in many total solar eclipse expeditions. One of these expeditions led him to the discovery of helium. Lockyer is also known as the founder of archaeoastronomy - the science that studies the astronomical meaning of ancient structures such as Stonehenge - and the author of many popular science books.