SEARCH CONTENT

You are looking at 1 - 10 of 704 items :

  • Industrial Chemistry, other x
Clear All Modify Search
In the Chemical, Petrochemical, Oil and Gas Industries
Raw Materials from Biotechnology
Risks and Regulations

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.