Giorgio Nebbia
Human society move into the future using every year (2009) an amount of energy equivalent to that embodied in about 11 billion tons of oil, about 460 EJ. Most of this energy "business" comes from oil, coal, natural gas, extracted from the bowels of the earth, fossil materials formats, hundreds of millions of years, the transformation of vegetal and animal substances, and no longer reconstitutable horizon (reasonably foreseeable) of humanity. Apart from a small village, fortunately on the decline, nuclear power, on a scale much smaller than the goods-energy comes from the motion of water such as hydropower, a stream provided by the cycle of evaporation and condensation generated from the sun, a stream that returns every year available, the goods-wide minimum energy is obtained from plants which convert solar radiation and wind energy into electricity. A certain amount of energy in countries and poor communities, is the burning of wood and agricultural waste, but that are largely beyond the accounting "official" international, although some estimates by the FAO indicate that energy from wood (trees and forest products) account for about 7 then for about 25-30% EJ, the world's energy needs.
The fraction of energy sales from renewable sources (water, sun, wind) is slightly more than 10 EJ is completely irrelevant to the flow of energy that the sun radiates on the surface of the Earth each year, about 3,500,000 EJ, EJ reach 1,000,000 in the land.
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In the beginning the twenty-first century we are approaching an era of scarcity of oil and, soon, including depletion of natural gas reserves. There remain large reserves of coal, but the transition to a society of coal requires the solution of scientific-technical and geopolitical issues very great: just to name one, oil is liquid and easily provides liquid fractions such as those suitable for existing engines automotive; the transformation of coal into transport fuel (even if going through hydrogenation processes which provide hydrogen or methanol) requires a revolution to which we are unprepared.
that remains is to look with new attention to the Sun that "works" every year 100 billion tons of plant products on land, causing the flow each year to 40 trillion tons of water on the surface of the continents.
Silent and perfect every day of the year in any part of the Earth, solar radiation provides the energy necessary to combine carbon dioxide from the atmosphere is the atmosphere and water and soil in organic molecules ( that ends with release of oxygen in the air). The first, relatively simple products containing carbon, hydrogen and oxygen, formed in the first stage of photosynthesis, are transformed, thanks to nitrogen and many other elements from the soil, in a huge variety of molecules: carbohydrates, fats, proteins. And within each "class" of molecules, the nature indulges in every plant, to offer variety and substance for which expertise is unfortunately still largely incomplete. Some of these molecules are used by "animals" that, with as much imagination, transform the plant molecules in a number indescribable (as known) of organic molecules
Agriculture "economic", and livestock that depend on it, using only a very limited number of the wealth of nature, those for which there is an outlet for immediate or traditional, and yet if you explore just a little herbal substances present in smaller plants, for their potential commercial interest, it turns out numerous opportunities for industrial production, research and work.
The "synthetic revolution" that began in the early decades of the nineteenth century, has meant that today, with the exception of food, at least eighty percent of the over ten billion tons of goods that are consumed each year on Earth is the source "non-organic" (although the fossil fuels, coal, oil, natural gas, although, strictly speaking, are far from organic.)
The chemistry of synthetic products derived from oil has as barren imagination and curiosity of naturalists and chemists in respect of plant and animal products. For most people, wood is one of the tables, or panels particle board, or the source of cellulose for paper or for various types of rayon. But in reality each tree there are many substances such as cellulose (plural), hemicellulose, lignin, tannins, resins, etc., some of which have in the past, power and industrial activities could be used in future for many others.
conditions and geopolitical conflicts that have excluded some countries from access to certain materials (think self-sufficiency in the Soviet period, fascist and Nazi), or the occasional surpluses of agricultural products (in the period of great crisis in the together), or the temporary price increase and shortage of certain raw materials (for example, during the "oil crisis" seventies of last century), led from time to time to review the living resources as sources of raw materials and commodities, on the whole, however, in recent decades have been lost expertise, seeds, bacterial cultures, for it becomes increasingly difficult to a resurgence of industrial initiatives based on many techniques that were important in the past. It seems possible, however, some new trends.
The first is that it seems increasingly clear that the dependence of a world society of resources destined to run out as non-renewable, is "unsustainable." The Sun and products, "sources" that the sun produces every year, in the same as it is always the same type, it is essential to turn to for energy and goods for a company that is worried about his future or, as they say, "sustainable" (whatever that word means).
The second important reason for interest in the materials derived from the Sun depends on the increasing attention to the negative environmental effects of present goods: many goods synthetic petroleum, greet, to their appearance, as a means to "liberate" from the bondage of nature , considered to be designed and modified at will, are not biodegradable and remain intact long after use and create problems for other goods smaltimento.Molte synthetic (dyes, pesticides, additives) have proved harmful to human health and natural ecosystems, to the point of inducing the abandonment of the "new" products to return to natural products. One of the best known cases is that synthetic insecticide DDT, which had supplanted the pesticides based on derivatives of pyrethrum, and after some years, was banned and had to again use the same derivatives of pyrethrum.
The third trend is the fact that the synthetic production of goods is only possible in high technology facilities and concentration of capital and knowledge, which are only available in developed countries. Such goods are available to the countries of the South only if they accept a position neocolonial dominated by international capital. There are signs of growing impatience with this perspective and a growing focus on goods that can be obtained from the great natural resources of biological origin and constantly renewable, that many countries of the South have, with facilities built and in operation on site. The publications of the FAO and other international bodies clearly show this trend.
in favor of birth or rebirth of activities associated with agriculture, forestry, animal husbandry, the richness of the biomass, in short, is the fact that the millions of plant and animal species existing in nature, only a few hundred thousand are were observed and characterized scientifically e hanno ricevuto un "nome", e soltanto di poche centinaia sono stati esplorati a fondo i caratteri botanici, zoologici e chimici in relazione al loro uso come fonti di materie prime e merci.
Il principio dell'economia tradizionale che spinge a utilizzare soltanto le materie che assicurano una elevata resa di "denaro" per unità di superficie coltivata o per unità di peso, ha provocato un graduale impoverimento delle varietà vegetali e animali utilizzate. Tale impoverimento è stato trasferito anche nei paesi sottosviluppati da cui vengono tratte molte delle materie di interesse commerciale. L'abbandono, per motivi di prezzo, di molte merci di origine naturale ha provocato un impoverimento della diversità biologica e la scomparsa fiber plants or used as sources of dyes and medicines, as well as many species of animals that have had commercial interest in the past.
One reason for optimism for the resumption of the use of many commodity resources lies in the enormous variety of biological molecules that they contain: as "chemistry" was born as "the chemistry of natural substances, attention to these substances has been declining, because of their commercial interest of the child. The pharmaceutical industry is probably the only one that is still convenient for the preparation of new medicines from natural molecules subject to change.
There is another interesting aspect: the commercial production products, especially foodstuffs in industrial countries requires the use of processing and preservation techniques that generate large quantities of by-products rich in organic molecules that often create disposal problems and pollution sources. Think of the canned products and waste industry, the dairy industry, industry of slaughtering and meat processing, and so on. We can calculate that every two pounds of dry organic matter from organic food that comes in the current cycle, at least one kilogram or even end up in waste in the trash. A closer knowledge of the chemical composition and physical character of these differences may allow to recover large quantities of goods being used as "secondary materials" such products.
The grounds for optimism for a product category based on materials from the "solar" is the great imagination that nature manifests itself in its organic synthesis. About 60% of the biomass plant is carbohydrates such as sugars, cellulose, starch, which are then the first materials that formed in the process of photosynthesis. --- With only three atoms of carbon, hydrogen and oxygen --- the nature of "factory" in a wide variety of combinations, diverse materials, often gathered for the first phase of development of seeds, sometimes as building materials capable of carrying water and inorganic salts from the soil to tens meters in height.
of this great biomass, available at a rate of about 60 billion tons a year, only a small part --- three or four billion tons a year --- it is used for humans. The paper industry, which absorbs each year many hundreds of millions of tons of lignocellulosic materials, goes looking for their raw materials on the basis of the need to obtain the "cellulose" standard suitable for its production cycles. The textile industry uses a very limited number of cellulosic fibers, compared to the wide variety of materials offered by nature. The chemical industry produces, sometimes painfully, synthesized molecules that have been and can be obtained via microbiologica dai carboidrati.
Fra la fine dell'Ottocento e i primi decenni del Novecento l'attenzione dei chimici è stata rivolta ai derivati chimici della cellulosa e si è così visto che le modificazioni dei vari gruppi funzionali alcolici consentivano di ottenere numerose sostanze, per la maggior parte poi abbandonate per il loro scarso interesse finanziario immediato. Sono sopravvissuti alcuni acetati come fibre artificiali o materie per pellicole, di limitata produzione, e i nitrati utilizzati come ingredienti per esplosivi. Il successo delle pellicole di polimeri sintetici ha spazzato via l'interesse per quelle di cellulosa rigenerata (tipo cellophane) che pure presentano importanti proprietà di permeabilità ai gas, ai liquids and biodegradability.
A better understanding of the lignin --- lignocellulosic materials accompanying the cellulose at a rate of about one part every two or three parts of cellulose --- could make a contribution to new ways of using paper and paperboard used in front an increasing difficulty of the operations for their transformation into new paper products.
The other major class of macromolecules of carbohydrates are the starches, substances with very different composition and molecular weight, ranging from one plant species to another and capable of transformation into many derivatives, so far little studied. For microbiological or chemical hydrolysis of starch are formed numerous substances, "Dextrins", as highly variable chemical and physical characteristics and use only a limited extent. Similar considerations apply to many sugars from monosaccharides such as glucose, disaccharides, sugars "rare", which exists in large quantities in nature and biological properties of which little is known. Many of these are capable of providing products, some of which are known from the chemical point of view, but so far little or nothing studied in terms of technical properties that probably would open the door to many employment sectors.
The proteins present in all plants and animals, are the foundation stones for all biological phenomena. The nature, with infinite imagination, starting da un limitato numero di amminoacidi, che sono le "pietre fondamentali" delle proteine, ha predisposto i comuni materiali da costruzione per organi vitali tanto diversi fra loro. Nelle pareti cellulari delle foglie, nel sangue animale, nelle ali delle farfalle, troviamo proteine diversissime come caratteri e funzioni; la diversità deriva dalle proporzioni in cui sono presenti tali amminoacidi e della loro successione.
Nonostante la varietà delle proteine esistenti in natura soltanto pochissime hanno ricevuto attenzione, al di fuori degli usi alimentari e di quelli dell'industria conciaria e tessile (seta, lana). Poche sostanze proteiche (quelle della caseina, della zeina, dell'arachide) sono state utilizzate per la produzione di artificial, now abandoned. Yet every year millions of tons of protein food industry, from whey, which are present in the residue from the extraction of fats, slaughterhouse waste and tannery operations, etc., are poor for uses such as power livestock, or the fertilization of soils, even when they are not thrown way constitute sources of pollution. Many of these proteins are of animal origin, rich in essential amino acids, and could be used for the integration of poor food, such as those that are the basis of nutrition in many countries of the South.
The same considerations apply to the fantasy of nature lipids, the constituents of the oils and fats of plant and animal origin, which are also produced industrially, especially for food, in an amount of about 100 million tons a year. The success of synthetic surfactants and synthetic glycerol reduced the field of industrial application of natural fats: here the considerations "green" has brought to life, in household detergents, albeit limited, certain types of soaps because of their agricultural biodegradability.
There are many avenues open for use, with success, natural dyes, gums and resins, terpenes, many vitamins and sterols, especially in those cases in which properties di interesse commerciale sono associate a strutture chimiche abbastanza complicate e non riproducibili per via sintetica.
A puro titolo di curiosità, e come esempio della potenziale ricchezza di moltissimi prodotti quasi sconosciuti del Sud del mondo, si può ricordare la storia della produzione, nel 1951, da parte dell'industria messicana Syntex, del cortisone dalla diosgenina ricavata dalla radice dell'igname messicano; lo stesso gruppo di chimici americani e messicani, operando nel Messico, preparò, sempre nel 1951, dal testosterone il contraccettivo orale noretindrone, "la pillola" (è questo il titolo di un libro di Carl Djerassi, pubblicato da Garzanti, che racconta tutta questa avventura) che avrebbe fatto diminuire the growth rate of world population and revolutionized sexual mores of billions of pairs. This is an example of how the revolution of biomass could grow in the South and new industries, research and production based on local materials.
The challenge of that nature offers in vegetable and animal products produced each year, with extraordinary regolatrità and on time from the Sun, such a great variety and complication of substances can be accepted only with as much imagination and chemical research. We are facing a difficult chemistry, but that is why the chemical and firms in developed countries could commit themselves, using the finest tools available today to create new goods, processes and employment opportunities, with benefits both the South and the North of the world, remembering that many solutions have been found and were then abandoned, with a depletion of the wealth of knowledge, a process similar to the loss of biodiversity values.
At this point I would respectfully recommend that we pay attention, in consultancy firms, industries, universities, what could be done to characterize, detect, process, the wealth of material goods "solar". A "solar product category" that could start going to bring to light experiences and knowledge of the past forgotten, and which may perhaps in future years e decenni, dare un contributo per farci uscire dalle trappole di un cammino che per ora continua a manifestarsi insostenibile.
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