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Series: De Gruyter STEM
Series: De Gruyter STEM
Fundamentals and Applications
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Abstract

Light olefins such as ethylene, propylene and butylene are mainly used in the petrochemical industry. Due to the growing need for light olefins in the industry and the future shortage of petroleum resources, the process of converting methanol to olefins (MTO) using non-oil sources has been considered as an alternative. Coal and natural gas are abundant in nature and the methods of converting them to methanol are well known today. Coal gasification or steam reforming of natural gas to produce synthetic gas (CO and hydrogen gas) can lead to methanol production. Methanol can also be catalytically converted to gasoline or olefins depending on the effective process and catalyst factors used. Due to the use of crude methanol in the MTO unit and because the feed does not require primary distillation, if the MTO unit is installed alongside the methanol unit, its capital costs will be reduced. The use of methanol can have advantages such as easier and less expensive transportation than ethane. Among the available catalysts, SAPO-34 is the most suitable catalyst for this process due to its small cavities and medium acidity. One of the problems of MTO units is the rapid deactivation of SAPO-34, which can also be affected by the synthesis factors, so it is possible to optimize the catalyst performance by modifying the synthesis conditions. In this article, we will introduce the MTO process and the factors affecting the production of light olefins.

Abstract

This review covers over 20 monomeric platinum complexes of Pt{η2-P(X)nP}Cl2 (n = 9–15, 17, 19) type. The chelating P,P-donor ligands create wide varieties of the metallocyclic rings: 12-membered (PC9P, PC3NCNC3P), 13-membered (PC3NC2NC3P), 14-membered (PC11P, PO(SiO)5P, PC2OC2OC2OC2P), 15-membered (PC12P), 16-membered (PCOC9OCP), 17-membered (P(C2O)4C2P), 18-membered (PC2OC9OC2P, PC4NC2NC2NC4P), 20-membered (P(C2O)5C2P), and 21-membered (POC2NC10NC2OP). For these complexes the most common is a predominantly cis-arranged with 17 examples and only four examples with trans-configuration. The total mean values of Pt–L bond distances in the complexes with cis- versus trans-configuration are: 2.252 Å (P trans to Cl), 2.355 Å (Cl trans to P) vs 2.288 Å (P trans to P), and 2.304 Å (Cl trans to Cl). There are examples which exist in cis- and trans-isomeric forms and distortion isomers. A brief survey on the structural data of almost 180 examples of Pt{η2-P(X)nP}Cl2 (n = 1–8) type complexes is added and discussed.

Abstract

The indium complexes are being used in many applications like catalysis, optoelectronics, sensors, solar cells, biochemistry, medicine, infrared (IR) mirrors and thin-film transistors (TFTs). In organometallic complexes of indium, it forms different types of complexes with single, double, triple and tetra linkages by coordinating with numerous elements like C, N, O and S and also with some other elements like Se and Ru. So, the present study comprises all the possible ways to synthesize the indium complexes by reacting with different organic ligands; most of them are N-heterocyclic carbenes, amines, amides and phenols. The commonly used solvents for these syntheses are tetrahydrofuran, dichloromethane, toluene, benzene, dimethyl sulfoxide (DMSO) and water. According to the nature of the ligands, indium complexes were reported at different temperatures and stirring time. Because of their unique characteristics, the organometallic chemistry of group 13 metal indium complexes remains a subject of continuing interest in synthetic chemistry as well as material science.