3 research outputs found
RENEWABLE NATURAL RAW MATERIALS ARE THE BASIS FOR THE PRODUCTION OF MULTIFUNCTIONAL BIOPOLYMER REAGENT SYSTEMS FOR USE IN OILFIELD CHEMISTRY
The relevance of the study is caused by the need to use both non-renewable and renewable natural resources to meet the energy needs. The purpose: the use of renewable raw materials with similar technological characteristics (starch, guar gum and neutral lignosulfonate) to create new reagent systems LKR-1 and LGKR-1 for application in oilfield chemistry, in particular as part of drilling fluids for use in the construction of oil and gas wells. Methods: set of existing basic methods for studying the properties of raw materials and synthesis products of natural polymers; evaluation and analysis of consistency index and nonlinearity coefficient (Brookfield viscometer), rheological (Fann rotary viscometer) and filtration properties (Fann filter press) of the developed reagent systems and known brands of gums. Results. It is shown that for Russia the issue of the competent use of renewable raw materials products is relevant, since it is a world leader in the possession of forest reserves and timber. The structure of wood as a polymer composition and the main components of both deciduous and coniferous species – cellulose, camels, starch, lignosulfonates – are presented. The paper introduces the list of domestic and foreign scientists whose works are devoted to the research and application of natural polymers in oilfield chemistry, products of renewable natural raw materials. The authors considered the influence of the main natural polymers used in oilfield chemistry and their modified forms on the technological parameters of process fluids. The properties of the developed reagent systems and their components are considered, and the presence of pseudoplastic properties of the LCR-1 reagent system is established, despite the fact that its components – starch and lignosulfonate – do not possess these properties. It was found that the component of the LGCR-1 reagent system, guar gum of plant origin, gives the developed reagent pseudoplastic properties comparable to the properties of reagents based on more expensive xanthan gum of the enzymatic production method
Tetrel, Chalcogen, and Charge-Assisted Hydrogen Bonds in 2-((2-Carboxy-1-(substituted)-2-hydroxyethyl)thio) Pyridin-1-ium Chlorides
Reaction of 2-chloro-2-(diethoxymethyl)-3-substitutedoxirane or 1-chloro-1-(substituted) -3,3-diethoxypropan-2-one with pyridine-2-thiol in EtOH at 25 °C yields 3-(diethoxymethyl)-3-hydroxy-2-substituted-2,3-dihydrothiazolo[3,2-a]pyridin-4-ium chlorides, which subsequently, in MeCN at 85°C, transforms into ring-opening products, 2-((2-carboxy-1-(substituted) -2-hydroxyethyl)thio)pyridin-1-ium chlorides. The tetrel (C···O) and chalcogen (S···O) bonds are found in the structures of 5 and 6, respectively. Compound 6 is also present in halogen bonding with a short O···Cl distance (3.067 Å). Both molecules are stabilized in crystal by tetrel, chalcogen, and multiple charge-assisted hydrogen bonds