The chemical industry
Abstract
In this chapter the evolution of the use of raw materials and processing technologies over the history of humankind is discussed. The aim is to present a brief history of the processes that will be evaluated throughout the text. Thus this chapter provides an overview to show why and how different raw materials gained support over time and the processing technologies evolved from simple processes to those used currently, based on a detailed understanding of the physical–chemical–biological foundations. Finally, a brief comment on the chemical industry (in figures) is presented at the end of the chapter.
Keywords
Chemical industry; process development; industrial chemistry
1.1 Evolution of the Chemical Industry
Chemicals and materials have been used and developed by mankind over centuries. Human history has traditionally been divided into eras directly related to the evolution of the use and processing of materials, that is, the stone and iron eras. Fig. 1.1 shows this evolution, from natural polymers and ceramics in 10,000 BC, to the development of synthetic materials via metals processing back in the Middle Ages, sponsored by the wars in Europe. In this chapter we will see how mankind’s evolution and needs have guided the development of the chemical industry.
The journey starts at the beginning of society with the use and manipulation of natural products. The more demanding society became, the more complex products and efficient processes were needed. This chapter will be the link between all the chapters included in this book. We focus on chemical process analysis when and why they originated, and how they evolved over decades to improve the quality of products and meet the needs of industry at every turn. The story begins with the use of natural products and the principles of biotechnology for food-related activities. The main turning point was the moment the first chemical process as we know it today was put together, 1746. It corresponds to the lead chambers Roebuck used for the production of sulfuric acid within the NaCl industry.
For simplicity, this timeline is divided into eight stages, from prehistory to today. Note that a more detailed analysis would lead to a more segmented timeline, but for the sake of argument and the purpose of this introductory chapter, this will suffice (García et al., 1998, Ordóñez et al. (2006a, 2006b)).
1.1.1 Prehistory
In the beginning mankind was nomadic, satisfying its needs directly from nature. Little or no transformation was needed, and if anything, it was craftwork.
1.1.2 First Settlements
However, as society changed from nomadic habits to established settlements, needs also underwent similar drastic changes. The discovery of fire and its control allowed cooking and curing of meat for preservation as smoked meat. As expected, food was a primary concern for mankind. Other methods such as solar curing or the use of salts as preservatives, which already required chemicals or chemical transformation, were also used. Salt production was therefore a need, and the evaporation of seawater was the method of choice.
Cave paintings dating back to 10000–5000 BC were the first evidence of the establishment of mankind into groups, but they also represented the capability of producing pigments out of natural species. As a result, mankind no longer looked to nature to satisfy its needs, but started developing its own means. For instance, around 7000 BC the use of fire allowed the production of fired-clay pottery. Crop irrigation has been known since 5000 BC. Several hundred years later copper artifacts were also used. Stone tools were developed and used by 4000 BC, and the wheel can also be dated back to this time. Most of these tools were used to grow and produce food. There is evidence of the domestication of cattle from 4000 BC. Also by that time, early biotechnology appeared. For instance, bread was produced in Egypt from 3500 BC, the production of cheese dates back to 2000 BC, yogurt out of fermented milk was created by central Asian People in the Neolithic period, barley beer can be dated back to 2500 BC in ancient Egypt, and by the same time rice beer was being produced by the Chinese. Furthermore, butter and natural glue gave rise to certain chemical and biochemical craftwork.
Animal skins have been used for protection via the production of garments, clothing, shelter, carpets, or decoration. One of the main issues, as with any other natural resource, was its preservation. Leather tanning using tree bark is said to have originated among the Hebrews. The techniques developed were kept as professional secrets and passed down through generations from father to son under a halo of magical foundations.
The first well-established generations were born in the Mediterranean area. Grapevine and olive trees are widely available in these regions. Mankind used both resources in several ways. From olive trees, oil was obtained as a means to cook food, to preserve it, and to use it as fuel for lighting. From the grapevine mankind obtained juice, and via fermentation, wine, which later aged into vinegar. For ages, vinegar was the strongest acid known to man.
These established civilizations also developed gypsum (2500 BC), and pigments for house and personal decoration. In terms of personal care, perfumes, dyed textiles, and paints appeared, which indicates a certain degree of developed craftwork. As we can see, it was society that demanded such products to improve the quality of life.
1.1.3 Alchemists
Knowledge of how to obtain and process raw materials was scattered. The ancient Greeks developed certain basics to explain these transformations. Although the theories were not correct—that is, the theory of the four elements—they worked in terms of pursuing rational thinking about natural processes.
The rational thinking from the ancient Greeks, together with theocentric concepts from Arabs and Christians, resulted in what is known as alchemy, an Arab word. Although it was surrounded by a magic halo, alchemists developed and prepared a large number of new materials and chemicals such as acids, alkalis, salts, etc. That also allowed improvements in perfume and dye production, as well as metallurgic developments. The aim of this development was more mystical: the search for eternal youth and the philosopher’s stone.
Around the 13th century, the center for knowledge moved from the East to the West. Universities, by putting together Greek knowledge, Arab and Jewish learnings, and Christian ideas, created the origins of the Renaissance, an intellectual revolution.
1.1.4 Lower Middle Ages
As civilization developed in Europe during the 12th and 13th centuries, textile production transferred to villages and towns, where workers in the same fields united in trade guilds becoming rather powerful. Thus, through the middle ages the use of iron spread not only as a material for agriculture and domestic tools, but as weapons too. Wars were the reason for the huge development of metallurgy. By this time mankind learned how to improve the taste of wine, bread, and cheese. Furthermore, the origin of a certain chemical industry was in place from basic natural species:
1.1.5 Middle Ages
Around the 14th century, strong acids such as chlorhydric acid, nitric acid, the mixture of both, and sulfuric acid (oil of vitriol) appeared. The discovery of sulfuric acid is as important to the chemical industry as the discovery of fire, since it allowed the preparation of a number of salts and other acids.
Although the aim was still the search for eternal youth, along the way a number of chemicals with interesting properties were produced, such as sodium sulfate, a laxant, and chloride as a byproduct from the production of chlorhydric acid using sulfuric acid and sodium chloride:
Furthermore, commercial trade increased as a result of the ideas in the Renaissance and the geographic discoveries in the 13th and 14th centuries. Both contributed to the development of larger manufacturing centers. However, the demand was limited to a few privileged classes, nobles, and clergy, which slowed down technological development.
During this preindustrial period, a number of activities that can be considered to belong to the chemical industry were carried out in the fields of metallurgy, chemical medicine, and the production of glass, soap, powder, and inorganic acids (based on craftsmen’s knowledge). For instance, Lazarus, Eeker, and Agrícola in the 16th century produced nitric acid from salt and ferrous sulfate.
1.1.6 Industrial Revolution
Transition from the craft-based production system to the industrial one required the identification and further understanding of the principles and foundations of nature. Lavoisier’s work by the end of the 18th century can be considered as the beginning of chemistry as a modern science. Thus, the chemical composition of some of the most common products was becoming known by the beginning of the 19th century. The basis of the chemical processes has its foundations in John Dalton’s atomic theory and Jöns Jacob Berzelius’s work to develop the Periodic Table. Organic species were gaining attention thanks to the work of Friedrich August Kekule, founder of the Theory on Chemical Structure, and Stanislao Cannizzaro.
As a result, industry specialized. A particular industry will not cover the entire process from raw materials into final products as the craftmen used to do. The chemical industry is divided into three categories:
1.1.6.1 Siderurgy
This is the first industry that grew following the commercial trades. In the beginning, charcoal from wood was used as a fuel and reductor agent. However, its scarcity due to the diverse uses of wood, such as in the naval or construction industries, and its use as fuel, limited the progress. The use of mineral coal was unsuccessful for quite some time due to the problems related to the presence of sulfur, the amount of volatiles, and the fact that the increase in the mass during preheating was troublesome for the furnace. It wasn’t until 1735 that Abraham Darvy first produced coke out of mineral coal. John Wilkinson improved the production process by building the coal heaps around a low central chimney built of loose bricks with openings for the combustion gases to enter. In 1802 the first battery of beehives was put together near Sheffield, and by 1870, 14,000 beehive ovens were already in operation in the coalfields of West Durham. During the 18th century, coke became the source for growth as it allowed the development of the stream engine, a basic component of the Industrial Revolution.
1.1.6.2 Textile industry
The steam engine was the driver for a number of craft-based industries since it allowed higher production rates, specialization, and division of work. This fact changed the way industry was conceived. Artisans lost their dominium over tasks and, in England, class differentiation vanished as a result of the Industrial Revolution. The first steam engine dates back to 1705 (Newcommen and Carley), but it was James Watt who from 1765 to 1868 increased the energy efficiency. Soon after, it was applied to power looms to weave sheds. As a result of the growth of the textile industry, a number of other industries also developed since larger amounts of dyes and bleaches were needed. Nature was not able to provide such quantities and the chemical industry grew to provide those chemicals: acids and alkalis.
1.1.6.3 Sulfuric acid industry
The production of acids focused its efforts on the oil of vitriol, since it allowed the production of other acids. The first method was lead chambers, initially proposed by John Roebuck in Birmingham in 1746. It consisted of large chambers internally covered by lead to protect the structure from corrosion, where sulfur oxides, steam, and oxides of nitrogen were put into contact. The presence of nitrogen oxides was required for the reaction to progress. In 1775 Lavoisier found the composition of the acid and a few years later, in 1778, Clement and Desormes showed that the nitrogen oxides were actually the catalysts for the production of sulfuric acid. It wasn’t until 1828 that Gay-Lussac modified the original process by adding the tower (that nowadays is named after him) to recover the nitrogen oxides. The needs for more concentrated acid, in particular for its use in the Leblanc process, resulted in another step forward in sulfuric acid production. The Glover Tower was added to the process in 1859. The first facility using the enhanced process dates back to 1935.
Although the concentration of the acid produced using the modified lead chambers process was enough for the Leblanc process and for the production of orthophosphates for the fertilizer industry, it was not appropriate for the production of pigments and dyes, or for explosives, where nitration processes were the basis. The heterogeneous method, the contact process, was patented by Peregrine Phillips in 1831. It consisted of the oxidation of SO2 gas to SO3 using air with platinum as catalyst. However, there were still technical limitations to the use of this method. The purity of the gases required in the process and the initial low demand of the concentrated acid did not allow the industrial application of this method until 1870, when it became technically and economically feasible. By the end of the 19th century, the Badische Anilin und Soda Fabric (BASF) produced sulfuric acid at industrial scale using platinum first as catalyst. Platinum was substituted by V2O5 during the First World War.
Sulfuric acid production was for years an indicative index of the development of a country.
1.1.6.4 Sodium carbonate industry—soda processes
At the beginning of the 19th century, Leblanc suggested the production of sodium carbonate from salt and sulfuric acid. This process was the turning point for the world’s chemical industry. In particular, we need to highlight the fact that for the first time the economic feasibility of the process was obtained only by reusing the byproducts hydrochloric acid (HCl) and sulfur (S).
HCl could be recovered by absorption. In 1836 William Gossage designed the Gossage Tower to recover HCl from the gas phase based on its solubility in water. He realized that contact area was key for the process. From that solution, chlorine (Cl2) was obtained from oxidation. Cl2 was (and still is) used as a disinfectant and bleach. In the case of S recovery, the Claus process patented in 1883 allowed sulfur recovery from the wastes of the Leblanc process.
The main drawback of the Leblanc process was the low purity of the sodium carbonate, which drove the development of the Solvay process by Ernest Solvay in the 1860s. The process breakthrough was the so-called Solvay Tower, which solved the technical problems of the first process patented by H.G. Dyan and J. Henning in 1834.
1.1.6.5 Coal gas industry
William Murdoch from 1792 to 1798 used coal gas for illumination of his own house. He was hired by the Boulton and Watt firm, and they began a gaslight program to scale up the technology. However, electricity soon replaced it. From the coal gas industry, as well as in the production of coke, there were a number of wastes and byproducts, discarded at first, that could be used. From the ammoniacal effluents, ammonia could be recovered and later sold as ammonia sulfate, a fertilizer. On the other hand, the growth of the organic chemical industry was due to the other residue, the coal tar, which was a raw material for a wide range of products.
The first organic compound artificially synthesized from inorganic materials was urea. It was obtained by treating silver cyanate with ammonium chloride by Friedrich Wöhler in 1828. From coal tar, Ruge in 1843 separated phenol, aniline, and other compounds. Aniline was the raw material for the first synthetic dye, aniline blue, patented in 1856 by Perkin.
Explosives were the other main chemicals, produced in 1885. Trinitrophenol was adopted by France and England, and trinitrotoluene was selected by Germany. Both substituted nitrocellulose and nitroglycerine which were highly unstable.
By that time (1892) calcium carbide (CaC2) was accidentally obtained in an electric furnace by Thomas L. Willson while he was searching for an economical process to make aluminum. The CaC2 was the raw material for the production of calcium cyanamide, a fertilizer, and for ammonia production via alkali hydrolysis. On the other hand, the decomposition of CaC2 with water generated acetylene, which later was used as the origin of many other organic compounds (ACS, 1998).
The development of the chemical and pharmaceutical industries, and the production of dyes, placed Germany at the top of the world’s chemical industry for decades. The discovery of the dynamo in 1870 was the origin of electrochemistry.
1.1.7 Industrial Society
The increasing quality of life in developed countries created new needs in the transportation and communication sectors, as well as a significant increase in the demand of some others. For instance, society demanded services including water, gas, power, and better buildings and houses. All of them implied larger energy consumption. The chemical industry was energy intense and thus it guided, the development of the power industry, improving the use of hydraulic resources, coal, and later, crude oil.
1.1.7.1 Nitric acid industry
It was the need for pigments and explosives that increased the demand for nitric acid. Before First World War (WWI) it was produced from sodium nitrate (Chile saltpeter or Peru saltpeter) and sulfuric acid. However, Chile saltpeter was the only natural source for nitrogen-based fertilizers, and thus both industries competed for the same raw materials. Therefore, there was a need for a different source of nitric acid for the chemical industry.
By 1840 Frédéric Kuhlmann studied the production of nitric acid via ammonia oxidation over platinum. The process did not reach industrial scale until the beginning of the 20th century when Ostwald and Eberhard Brauner found the operating conditions for an acceptable yield. The use of ammonia was an alternative path towards nitric acid, however, ammonia was also basic to the fertilizer industry.
The problem was solved in 1913 when the Haber–Bosch process—named after Fritz Haber, a chemist, and Carl Bosch, an engineer with the Basiche firm—was discovered. The reaction, carried out at high pressures and temperatures over metallic oxides, was a challenge for the field of materials and reactor design, representing:
• Development of heterogeneous catalysis.
• Production of pure N2, obtained from air involving cooling, condensation, and air rectification. In essence, air fractionation and the Linde process were developed behind this need.
• Production of pure and reasonably cheap hydrogen, by developing coal gasification technologies followed by the water was shift reaction to get rid of the carbon monoxide (CO) that was produced together with the hydrogen.
• Developed high-pressure and -temperature gas processing, in particular the problem of the high diffusivity of hydrogen and the material design to handle it.
1.1.7.2 Coal gasification
Coal gasification represented (in 1923) the establishment of carbon chemistry via the production of synthesis gas, syngas. Syngas mainly consisted of hydrogen and CO, the building block for a large number of compounds such as methanol, from which formaldehyde can be produced via oxidation and Bakelite by its polymerization (ACS, 1993).
Syngas was also a raw material for synthetic fuels. When Germany lost access to crude oil during the WWI, an alternative was presented that used syngas to obtain synthetic gasoline and diesel. The process was developed by Franz Fischer and Hans Tropsch, and patented in 1925. It was based on the hydrogenation of CO over catalysis. At the same time, the West lost its main supplier for pigments and intermediates, and thus the chemical industry grew by developing novel processes based on state-of-the-art technologies and improved organization and productive models. Thus the United States displaced Germany from its top position in the chemical industry.
1.1.7.3 Polymers
By the mid-1900s, the first modification of natural polymers such as cellulose and rubber was successful, making it possible to achieve new properties for novel applications. Furthermore, the unsuccessful experiments in processing several mixtures of small molecules resulted in viscous fluids or solids that were highly stable. The increased needs for modified macromolecular products provided an opportunity for the production of synthetic plastics from those small organic molecules, creating Bakelite (mentioned above), polyvinyl chloride, acrylic plastics, polystyrene, nylon, low-density polyethylene, etc., and making it possible to obtain tailor-made products with the proper properties. The chemical industry provided the raw materials and acetylene found a new use.
It was again as a result of a war, Second World War (WWII), that the supply of natural macromolecules was cut off. The only industry capable of substituting a natural species by a synthetic ones was, and still is, the chemical industry. That required research and development. For instance, when the United States could not access natural rubber, it took 2 years to develop synthetic rubber; by 1944 all vehicles used synthetic rubber for their tires. In 1954 the first catalysts capable of producing molecules with a certain 3D order were developed, the Ziegler–Natta. Novel and more specialized materials such as resins were thus developed.
1.1.7.4 Petrochemical industry
The source for most of the small molecules, the acetylene, was produced in an electric furnace from calcium carbide (CaO+3C→CaC2+CO). The high demand to satisfy the growing macromolecules market increased its price and the industry turned its focus to crude oil. Crude fractionation and refining was developed in the beginning of the 20th century in the United States.
The growth of the automobile industry and the demand of society for higher quality of life increased the demand for gasoline. Production via crude fractionation could not meet the demand, and therefore heavier fractions that could not be easily sold became the source for fuels (via cracking). We can trace cracking back to work by Burton and Humphries in 1912.
Apart from small molecules and gasolines, the production of aromatics became of great interest. Thus petrochemistry replaced carbochemistry due to the lower cost of raw materials and final products, and ethylene replaced acetylene as the building block of the chemical industry.
1.1.8 Renewable and Nonconventional-Based Development
The easy access to cheap and abundant raw materials slowed down the research on other energy sources and raw materials. However, the growth in population and increasing energy needs over the years, together with the political stability of the main producers, has moved society to find alternative sources of energy. There has been an important development of renewable-based sources of chemicals and power from not only biomass such as energy crops (switchgrass, miscanthus) and nonedible sources of oil (including algae), but also solar and wind energy. Lately a number of processes have been developed to produce substitutes for crude-based gasoline and diesel, such as bioethanol and Fischer–Tropsch gasoline and diesel, dimethyl ether, dimethyl furan, furfural from biomass, biodiesel, from waste cooking oil, algae or nonedible oil, glycerol ethers from the byproduct of the biodiesel industry. Typically solar and wind have been used for the production of power using photovoltaics or concentrated solar power facilities, and wind turbines, respectively. The difficulties in storing solar and wind energy have also been a challenge that the chemical industry has accepted either by the development of batteries or the production of chemicals such as methane from CO2 and electrolytic H2.
Apart from renewable-based sources, two nonrenewable but abundant sources of methane have attracted attention: shale gas and methane hydrates. Shale gas is natural gas trapped in shale formations. The development of extraction techniques, horizontal drilling, and fracking are currently allowing the exploitation of the vast reserves found in the United States, Mexico, Argentina, and China. Methane hydrate is actually methane trapped in ice that has been generated from organic wastes in the continental limits or below the ice of frosted surfaces. Hydrates represent more than 50% of organic carbon, and currently Japan has made interesting progress in the industrial use of this methane (Martín and Grossmann (2015)).
1.2 Chemical Industry in Figures
World chemical turnover was valued at €3156 billion in 2013; that is divided across several regions, as presented in Fig. 1.2. We can distinguish five major businesses within the chemical industry: polymers, petrochemicals, specialties, basic inorganics, and consumer chemicals. The share of the total industry is about 25% each for the first three, and the rest is divided almost equally between consumer chemicals and basic inorganics (see Fig. 1.3).
