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Abstract

The presented chapter deals with technological aspects concerning industrial production of major inorganic chemicals such as sulfuric, nitric and phosphorous acids. The idea was to highlight the main assumptions related to their fabrication as well as to point out novel aspects and perspectives concerning their industry. The main attention will be paid to raw materials and their transformation in order to obtain indirect precursors of inorganic acids - acid anhydrides. Characteristics of the individual stages of synthesis, with a special regard to the process conditions will be also of key importance. The environmental impact of this particular technology will be raised and discussed. Finally, the review over recently published scientific papers, concerning innovative solutions in inorganic acids production, will be performed.

Abstract

At present, Polylactic acid (PLA) is one of the most used biodegradable polyesters. The good properties and its biodegradability make that PLA can replace the fossil fuel derived polymers in different applications. PLA can be synthesized by using different methodologies. Among them, the most widely used forms on an industrial scale are the direct polycondensation of Lactic acid and the ring-opening polymerization of cyclic Lactide. The final properties of the obtained PLA are dependent on the used stereoisomers of the raw materials (Lactic acid and/or Lactide) and the conditions employed to polymerize them. Therefore, the comprehension of the synthetic mechanism of PLA is crucial to control the stereoregularity of PLA, which in turn results in an improvement of the polymer properties. So, distinct mechanisms for the synthesis of PLA by ring-opening polymerization using different catalysts systems (organometallic catalysts, cationic catalyst, organic catalyst, bifunctional catalysts) are examined in this review.

Abstract

Ammonia and sodium hydroxide are two important inorganic bases which served as the basis or precursors of other compounds with multiple uses. Some of their derived salts, i. e. ammonium nitrate, are of the paramount importance for daily life. Others salts, such as lithium carbonate, are gaining a primary role in the development of smart technologies, i. e. E-cars. This chapter described developments in the production of these useful compounds: ammonia, sodium and potassium hydroxides, related salts, i. e. ammonium nitrate, sodium and potassium carbonates, and finally, lithium carbonate.

Abstract

Plastics, thanks to their versatility, and high resource efficiency have become important materials in such branches as packaging, transportation, medicine, building and construction, etc. Although the role of recycling of various plastics in their manufacturing has been recently increasing (as a consequence of strong enhancement for circular economy, particularly in Europe), still production of monomers as substrates for plastics manufacturing is growing. It is predicted that, despite ongoing efforts to reduce, reuse, recycle and even ban plastic materials, improving living standards, population growth, and the lack of ready alternatives support the market for plastics for the next 20 years. The most important monomers produced on industrial scale belong to simple unsaturated hydrocarbons (alkanes/ olefins), called also hydrocarbon intermediates because they are substrates for further processes of organic synthesis or polymerization. A great variety of current technological approaches to olefins production was shown, i. e. steam cracking (SC), methanol-to-olefins (MTO), dehydrogenation (PDH, Catofin, Oleflex, STAR, FCDh), methathesis (OCT). The continuous improvement and development of onpurpose processes is a response to dynamic changes on feedstock market of petrochemical raw materials, consumer needs, and environmental regulations. It was emphasized that boom in dehydrogenation processes (particularly, PDH) results from shift to ethylene production in steam crackers, a gap between supply of propylene, butylenes and higher olefins compared to the continuously growing demand for their derivatives.

Abstract

Paper describes industrial synthesis of the most important alcohols (methanol and ethanol), organic acids (acetic and lactic), and fatty acid methyl esters (biodiesel). Also, current industrial solutions and global trends in manufacturing of these chemicals are presented. Moreover, several alternative production technologies of these chemical compounds are discussed, which might successfully replace current commercial methods in the future.

Abstract

The structural element of many organic compounds in which the carbon atom combines with the oxygen atom in a double bond is called the carbonyl group. Both atoms forming such a double bond are characterized by hybridization of the sp2 type. Spatially, these two atoms and two other atoms directly related to the carbon atom lie in the same plane. One of the carbon-oxygen bonds is of σ type, formed by two overlapping sp2 orbital bonds, while the other is of π type, realized through the commonalization of non-hybridized electrons from orbital π. The carbonyl group “-C=O” is a common element in the structure of aldehydes and ketones and to a large extent determines their chemical properties. Aldehydes are organic compounds in which the carbonyl group is connected by one single bond to the hydrogen atom and the other to the rest of the hydrocarbon molecule. In aldehydes, the C=O group occurs at the end of the carbon chain; it is connected with a single C-C bond; the fourth bond is saturated with hydrogen atom. Ketones are organic compounds containing a carbonyl group which is combined with two hydrocarbon groups. In ketones, the C=O group occurs within the carbon chain of molecules; the carbon atom of the carbonyl group is secondary. Ethers are organic compounds in which C-O-C bonds are present, where none of the carbon atoms is bound to more than one oxygen atom.

Abstract

This paper discusses the main technological solutions used in the production of key nitrogen derivatives such as nitrobenzene, aniline, ethanolamine, and methylene diphenyl diisocyanate. The technologies presented are not only already functioning technologies, but also the newest installations that are at the testing stage.

Abstract

Current trends in industrial synthesis of selected halogened hydrocarbons (HHCs) were presented in detail. Special emphasis was put on the most popular compounds, such as chloromethanes (CH3Cl, CH2Cl2, CHCl3, CCl4), chloroethene (vinyl chloride H2C = CHCl), chlorobenzene, 1-4-dichlorbenzene and epichlorohydrin. The possibility methods of modification technologies based on literature information were also reported. Presented simple schema, with production conditions, should be helpful in understanding the issues discussed.

Abstract

Surface active agents are amphipathic molecules that consist of a nonpolar hydrophobic portion, usually a straight or branched hydrocarbon or fluorocarbon chain containing 8-18 carbon atoms (tail), which is attached to a polar or ionic portion (hydrophilic head). The classification of surfactants refers to the behavior of head in solutions. Therefore, the hydrophilic portion can be nonionic, zwitterionic or ionic and accompanied by counter ions in the last case. The production technology of surfactants depends on the final structure of surfactant. The manuscripts describe the methods of obtaining the most important compounds such as soap, linear alkylbenzene sulfonates, methyl ester sulfonate, alcohol sulfates, alcohol ethoxysulfates, sulfosuccinates. Not only the anionic surfactant production method is presented but also cationic and amphoteric synthesis routes are shown. In the nonionic group of surfactants, several classes can be distinguished: alcohol ethoxylates, alkyl phenol ethoxylates, fatty acid ethoxylates, sorbitan ester ethoxylates, monoalkaolamide ethoxylates, fatty amine ethoxylates and ethylene oxide-propylene oxide copolymers. Another important class of nonionics is the multihydroxy products such as glycol esters, glycerol (and polyglycerol) esters, glucosides (and polyglucosides) and sucrose esters. Amine oxides and sulphinyl surfactants represent nonionics with a small head group. They are all produced and used widely throughout the world in a multitude of industries.

Abstract

The work presents the process of design using simulation approach. The fundamental unit operations were described including chemical reaction, separation in distillation units and heat exchange process together with thermodynamics considerations. Detailed description of the available methods and procedure is provided. The design process is based on the use of Chemcad software.