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Full-Text Articles in Catalysis and Reaction Engineering

Catalytic Effect Of Metal Ions On The Oxidation Of Thiocyanate Ions With Hydrogen Peroxide, Sarvar B. Rajabov, Salmon M. Mukhammadiev, Berdakh T. Daniyarov, Haci Deveci, Shahlo Sh. Daminova Sep 2026

Catalytic Effect Of Metal Ions On The Oxidation Of Thiocyanate Ions With Hydrogen Peroxide, Sarvar B. Rajabov, Salmon M. Mukhammadiev, Berdakh T. Daniyarov, Haci Deveci, Shahlo Sh. Daminova

CHEMISTRY AND CHEMICAL ENGINEERING

Thiocyanate (SCN⁻) ions, formed during the cyanidation of gold ores, pose a significant environmental problem when present in mine processing wastewater. In this study, the oxidation of potassium thiocyanate model solutions (10–1000 mg/L) with hydrogen peroxide, in the presence and absence of Cu2+ and Fe2+ ions, was investigated at room temperature. Residual SCN⁻ concentrations were determined by bromatometric titration and UV-spectroscopy. Without a catalyst, H2O2 showed the weakest effect at all concentrations, leaving 6–17% residual SCN⁻ even at the highest applied dose. The addition of Cu2+ and Fe2+ ions markedly accelerated oxidation via …


Photocatalysts Based On Titanium Dioxide And Zinc Phthalocyanine Composites For Photodegradation Of Methylene Blue, Albert R. Koldarov, Mastura Kh. Aripova, Odilzhon E. Abdurakhmonov, Zuhra Ch. Kadirova, Abror O. Tashpulatov Jun 2026

Photocatalysts Based On Titanium Dioxide And Zinc Phthalocyanine Composites For Photodegradation Of Methylene Blue, Albert R. Koldarov, Mastura Kh. Aripova, Odilzhon E. Abdurakhmonov, Zuhra Ch. Kadirova, Abror O. Tashpulatov

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this work is to analyze the photocatalytic degradation of a model methylene blue solution using titanium dioxide composites with zinc phthalocyanine as the sensitizing photocatalyst under sunlight. The objects of the study are TiO2-based photocatalysts derived from the spent catalyst of the Shurtan GCC after heat treatment at 650°C (T-650), as well as a composite containing zinc phthalocyanine (T-650/PcZn). It has been established that the photodegradation reaction follows a pseudo-first-order model, while the rate constant for the TiO2/PcZn composite is significantly higher than that of pure TiO2, indicating greater efficiency. The …


Kinetic Investigation Of The Sn2 Reaction Between Piperidine And Chloroacetic Acid Using Atr-Ftir Spectroscopy, Sadoqat O. Mamatkulova, Oytura S. Maksumova Mar 2026

Kinetic Investigation Of The Sn2 Reaction Between Piperidine And Chloroacetic Acid Using Atr-Ftir Spectroscopy, Sadoqat O. Mamatkulova, Oytura S. Maksumova

CHEMISTRY AND CHEMICAL ENGINEERING

In this study, the kinetic characteristics of the nucleophilic substitution (SN2) reaction between piperidine and chloroacetic acid were investigated in real time at 50, 60, and 70 °C using ATR-FTIR spectroscopy. The spectral analysis revealed a gradual decrease in the C–Cl stretching vibration in the 710–730 cm⁻¹ region and a simultaneous increase in absorption bands corresponding to the C–N bond in the 1020–1250 cm⁻¹ region, confirming the consistent progression of the reaction. Analysis of the conversion function X(t) showed values of X = 0.669 at 50 °C, X = 0.826 at 60 °C, and X = 0.970 at 70 °C, …


Development Of A Catalytic System Based On N,N’,N”-Tris-(Β-Oxyethyl)Hexahydro-S-Triazine For Polyisocyanuraturethane Foam, Murod K. Karimov, Nozima M. Alimukhamedova, Lochinbek M. Khurramov, Ravshan I. Adilov, Murafar G. Alimukhamedov Mar 2026

Development Of A Catalytic System Based On N,N’,N”-Tris-(Β-Oxyethyl)Hexahydro-S-Triazine For Polyisocyanuraturethane Foam, Murod K. Karimov, Nozima M. Alimukhamedova, Lochinbek M. Khurramov, Ravshan I. Adilov, Murafar G. Alimukhamedov

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this work is to develop a catalytic system for the production of polyisocyanurateurethane foams based on N,N',N"-tris(β-hydroxyethyl)hexahydro-S-triazine (TOEGT). N,N',N"-tris(β-hydroxyethyl)hexahydro-S-triazine (TOEGT) exhibits high catalytic activity in polyurethane foam production processes. However, it exhibited moderate catalytic activity in polyisocyanurateurethane  foams, the formation of which is characterized by the sequential-parallel reactions of urethane formation, isocyanate trimerization, and foaming (isocyanate + water). By varying the composition of the catalytic mixture, the required concentrations of each component were determined, which made it possible to synthesize polyisocyanurateurethane foams that meet the requirements of casting polyurethane foams. The optimal ratio of N,N',N"-tris(β-hydroxyethyl)hexahydro-S-triazine: triethylenediamine: tin …


Synthesis, Crystal Structure And Some Physicochemical Properties Of Cerium Complexes Containing Beta-Diketonate Ligands, Feruza F. Fayzullayeva, Salmon M. Mukhammadiev, Gulbeka Yu. Mamatova, Shahlo Sh. Daminova Mar 2025

Synthesis, Crystal Structure And Some Physicochemical Properties Of Cerium Complexes Containing Beta-Diketonate Ligands, Feruza F. Fayzullayeva, Salmon M. Mukhammadiev, Gulbeka Yu. Mamatova, Shahlo Sh. Daminova

CHEMISTRY AND CHEMICAL ENGINEERING

The objective of this study is to synthesize and characterize novel Ce(III) coordination compounds utilizing the β-diketonate ligand (1,3-diphenylpropane-1,3-dione). The structures of the resulting complexes were determined through single crystal X-ray diffraction (XRD). In these complexes, the oxygen atoms of the ligand form bidentate bonds with the metal ion. The geometry surrounding the cerium ion is described as distorted square antiprismatic, influenced by the flexibility and steric hindrance of the dibenzoylmethane (dbm) ligand. Additional characterization of the newly synthesized complex was performed using IR spectroscopy, thermal analysis, and scanning electron microscopy (SEM).


Synthesis Of Acetylene Diols In The Catalytic System Of Cu(Otf)2/Thf/Tbabr, Abduvakhаb Ikramov, Lochinbek Q. Ablakulov, Odiljon E. Ziyadullayev, Sardor M. Rakhmatov, Mirjalol E. Ziyadullayev Mar 2025

Synthesis Of Acetylene Diols In The Catalytic System Of Cu(Otf)2/Thf/Tbabr, Abduvakhаb Ikramov, Lochinbek Q. Ablakulov, Odiljon E. Ziyadullayev, Sardor M. Rakhmatov, Mirjalol E. Ziyadullayev

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the work was the synthesis of acetylenediols in the Cu(OTf)2/THF/TBABr catalytic system. The synthesis of acetylenic diols based on the alkynylation process of aliphatic and heterocyclic ketones containing two carbonyl groups in their molecules in the presence of alkyne hydrocarbons was studied for the first time using the Cu(OTf)2/THF/TBABr catalytic system. The effects of temperature, reaction time, nature of solvent and catalyst, and molar amount of starting materials on the synthesis of acetylenic alcohols in the selected system were studied, and based on the results obtained, alternative conditions for the process were found.


Synthesis And Study Of New Complex Compounds Of Copper(Ii) And (5-Methyl-1,3,4-Thiadiazole-2-Ylsulfanil)-Acetic Acid, Ekaterina V. Kinshakova, Aziz K. Atashov, Batirbay S. Torambetov, Shakhnoza A. Kadirova Mar 2025

Synthesis And Study Of New Complex Compounds Of Copper(Ii) And (5-Methyl-1,3,4-Thiadiazole-2-Ylsulfanil)-Acetic Acid, Ekaterina V. Kinshakova, Aziz K. Atashov, Batirbay S. Torambetov, Shakhnoza A. Kadirova

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this study is to synthesize new copper (II) coordination compounds with a heterocyclic polydentate ligand (5-methyl-1,3,4-thiadiazole-2-ylsulfanyl) -acetic acid and to study their structure. The structure of the complexes was established by the method of X-ray diffraction analysis (XRD) of single crystals, it was shown that the complexes have a polymer structure and a coordination polyhedron of the square pyramid type, however, one of them is mono-nuclear composition (C10H14CuN4O6S4*2H2O)n, and the second is bi-nuclear composition of cluster type (C20H20Cu2 …


Synthesis Of Acetylene-Based Hetarene Derivatives In The Presence Of Catalysts, Abdulla T. Umrzokov, Abduvaxаb Ikramov, Khusnitdin M. Vapoev, Yusuf K. Zhumanov, Sardor M. Kodirov Mar 2025

Synthesis Of Acetylene-Based Hetarene Derivatives In The Presence Of Catalysts, Abdulla T. Umrzokov, Abduvaxаb Ikramov, Khusnitdin M. Vapoev, Yusuf K. Zhumanov, Sardor M. Kodirov

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the study is to synthesize hetaren derivatives of acetylene amination reactions using local natural raw materials as catalyst carriers. Various grades of Oltintag and Angren kaolins, various grades of Navbakhor bentonite, as well as the opaque rock of the Karmaninsky deposit were used as catalyst carriers. Thermal, acidic and hydrothermal treatment was carried out on the appropriate sorbents, with the production of catalysts of various modifications from sorbents and active components. The processes of catalytic condensation of acetylene with ammonia were studied using modified catalysts. The effect of the reaction temperature, the active components of the catalyst, …


Synthesis Of Acetylene Diols With The Participation Of The Bu4noh/Dmso/H2o Catalytic Systems, Muyassar K. Salieva, Odiljon E. Ziyadullayev, Guzal K. Otamukhamedova, Rifkat F. Talipov, Lochin K. Ablakulov May 2024

Synthesis Of Acetylene Diols With The Participation Of The Bu4noh/Dmso/H2o Catalytic Systems, Muyassar K. Salieva, Odiljon E. Ziyadullayev, Guzal K. Otamukhamedova, Rifkat F. Talipov, Lochin K. Ablakulov

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this work in this study, acetylene alcohols containing heteroatomic substituents in their molecular composition- 2-(-thiophen-2-yl)but-3-yn-2-ol, 2-(3-methylthiophen-2-yl)but-3-yn-2-ol, 2-(furan-2-yl)but-3yn-2-ol, 2-(pyridin-4-yl)but-3-yn-2-ol, 2-(5-chlorothiophen-2-yl)but-3-yn-2-ol, 2-(5-bromothiophen-2yl)but-3-yn-2-ol acetylene diols were synthesized based on the reaction with acetone in a dimethyl sulfoxide solvent in the presence of the Bu4NOH/DMSO/H2O catalytic system. The influence of the molar ratio of starting materials, reaction duration, temperature, nature of the catalyst and solvents on the product yield was systematically studied. The composition, purity and structure of the new generation of synthesized acetylenediols have been confirmed by modern physicochemical methods. The mechanism of the reaction process …


Synthesis Of High Molecular Mass Resins Based On Furfuryl Alcohol, Boysayid U. Sayidov, Latif E. Jumanov, Muzaffar G. Alimukhamedov, Sherali A. Umarov, Farhod A. Magrupov May 2024

Synthesis Of High Molecular Mass Resins Based On Furfuryl Alcohol, Boysayid U. Sayidov, Latif E. Jumanov, Muzaffar G. Alimukhamedov, Sherali A. Umarov, Farhod A. Magrupov

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of the work is to study the process of synthesis of furfuryl oligomers with high molecular weight at various ratios of furfuryl alcohol and hydroxyl-containing polyether polyol. The influence of the process method on the yield of high-molecular furfuryl oligomer is shown - with a one-step synthesis method with an increase in the amount of furfuryl alcohol from 20 to 50 moles per 1 mole of polyether polyol, the yield of the final product decreases from 75% to 56%, apparently due to high exothermic effects, causing gelation systems. In contrast to the one-time introduction of the catalyst, its …


Synthesis And Technology Of Vinyl Esters Of Aromatic Carboxylic Acids Based On Vinyl Acetate, Askar B. Parmanov, Suvonkul E. Nurmanov, Saida S. Abdurakhmanova, Sarvinoz I. Tirkasheva, Begzod F. Adashev May 2024

Synthesis And Technology Of Vinyl Esters Of Aromatic Carboxylic Acids Based On Vinyl Acetate, Askar B. Parmanov, Suvonkul E. Nurmanov, Saida S. Abdurakhmanova, Sarvinoz I. Tirkasheva, Begzod F. Adashev

CHEMISTRY AND CHEMICAL ENGINEERING

In this work the vinylation reactions of aromatic carboxylic acids with vinyl acetate, which contain various substituents, in the presence of 2-chloro-4,6-dimethoxy-1,3,5-triazine were studied for the first time. The influence of the nature of the starting materials, temperature, reaction duration, solvent and reagents - zinc triflate (Zn(OTf)2, 3,3-diphenylbinaphthol (3,3'-Ph2BINOL-2Li), tertiary potassium butylate (KOtrBu), butyllithium (BuLi) for the synthesis of vinyl esters. The synthesis of vinyl esters of aromatic carboxylic acids was carried out: benzoiс, 2-phenylacetic, 4-methylbenzoic, 4-methoxybenzoic, 3,4-dimethoxybenzoic, 2-brombenzoic, 4-brombenzoic, 4-fluorobenzoic, 3-nitrobenzoic, 4-nitrobenzoic, 4-tertiary butylbenzoic, 2-chlorobenzoic, 4-chlorobenzoic, 3-hydroxybenzoic and 4-hydroxybenzoic acids has been studied. …


Synthesis Of Internal Acetylene Alcohols Based On The Sonogashira Reaction Of Terminal Acetylene Alcohols And Benzolchloride, Guzal K. Otamukhamedova, Odiljon E. Ziyadullayev, Abduvahob Ikramov, Sarvinoz I. Tirkasheva May 2024

Synthesis Of Internal Acetylene Alcohols Based On The Sonogashira Reaction Of Terminal Acetylene Alcohols And Benzolchloride, Guzal K. Otamukhamedova, Odiljon E. Ziyadullayev, Abduvahob Ikramov, Sarvinoz I. Tirkasheva

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of the study is to develop a new catalytic system for the synthesis of internal acetylene alcohols from the Sonogastric coupling reaction of terminal acetylene alcohols and benzolchloride. For the first time in this work, internal acetylene alcohols have been synthesized based on reactions of some terminal acetylene alcohols – 3,4-dimethylpentin-1-ol-3, 3,4,4-trimethylpentin-1-ol-3, 1-ethynylcyclohexanol-1, 2-ethynyladamantanol-2, 2-phenylbutin-3-ol-2, 2-(naphthyl-2)butyn-3-ol-2, 2-(furanyl-2)butyn-3-ol-2 and 2-(pyridinyl-4)butyn-3-ol-2 with chloridebenzene. In order to achieve high product productivity in the Sonogashira reaction, alternative conditions have been identified by studying the molar ratios, spatial structure, induction effects of substituents, solvent and catalyst nature, as well as temperature, reaction duration …


Study Of Reactive Distillation Equipment For Eterification Process, Abbos Elmanov, Abdulaziz Bakhtiyorov, Adham Norkobilov, Olimjon Maksudov, Zarif Oripov Apr 2024

Study Of Reactive Distillation Equipment For Eterification Process, Abbos Elmanov, Abdulaziz Bakhtiyorov, Adham Norkobilov, Olimjon Maksudov, Zarif Oripov

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this work is to study the chemical technological processes for eterification processes, and the reactive distillation unit, which carries out the reaction and separation process in one device, was chosen as the object of research. А reаctive distillаtion system is exаmined to produce for the production of Ethyl Acetate (EtAc) viа eterificаtion of acetic acid (HAc) with ethаnol. Optimizаtion methods using sensitivity analysis аre аlso conducted. Cаlculаtion of vаpor liquid equilibrium of the mixture system is done using UNIFАC model. Heat integration from the distillate stream of the column to the acid feed stream and from bottom …


Alkynylation Of Benzaldehyde And Its R-Substituted Derivatives Based On Lithium Phenylacetylenide, Sanat B. Samatov, Odiljon E. Ziyadullayev, Abduvakhab Ikramov Apr 2024

Alkynylation Of Benzaldehyde And Its R-Substituted Derivatives Based On Lithium Phenylacetylenide, Sanat B. Samatov, Odiljon E. Ziyadullayev, Abduvakhab Ikramov

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this research work is for the first time the synthesis of the corresponding acetylene alcohols based on the alkynylation reaction of isolated benzaldehyde and its R-substituted derivatives in the BuLi/TGF system. The study proposed the reaction stages for the synthesis of acetylene alcohols in the selected BuLi/TGF system, the influence of factors influencing the process, including temperature, reaction duration and nature selected solvents. The structure of the synthesized acetylene alcohols was confirmed by modern methods of physicochemical analysis (1H NMR, 13C NMR). In addition, the effect of substituents in benzaldehyde and its R-substituted derivatives …


Kinetics Of Carboxymethylation Reaction Of Cellulose Samples With Different Degree Of Crystallinity, Ilkhom Goyibnazarov, Sherzod Yuldoshov, Abdushukhur Sarimsokov May 2022

Kinetics Of Carboxymethylation Reaction Of Cellulose Samples With Different Degree Of Crystallinity, Ilkhom Goyibnazarov, Sherzod Yuldoshov, Abdushukhur Sarimsokov

CHEMISTRY AND CHEMICAL ENGINEERING

No abstract provided.


Mathematical Modeling Of Synthesis 4´,4´´-Di-(1-Methyl-1-Hydroxy-2-Phenylethynyl)-Dibenzo-18-Crown-6, Lyubov Kozinskaya, Dilorom Mirkhamitova May 2022

Mathematical Modeling Of Synthesis 4´,4´´-Di-(1-Methyl-1-Hydroxy-2-Phenylethynyl)-Dibenzo-18-Crown-6, Lyubov Kozinskaya, Dilorom Mirkhamitova

CHEMISTRY AND CHEMICAL ENGINEERING

The main goal of this study is the mathematical modeling of the optimal conditions for the synthesis of 4´,4´´-di-(1-methyl-1-hydroxy-2-phenylethynyl)-dibenzo-18-crown-6 by the least squares method. In the STAT program, iconograms of mathematical modeling of the synthesis and the dependence of the rate of formation of 4´,4´´-di-(1-methyl-1-hydroxy-2-phenylethynyl)-dibenzo-18-crown-6 on temperature and reaction time were obtained, the corresponding analytical dependencies are determined. Mathematical processing of the results of the synthesis of 4´,4´´-di-(1-methyl-1-hydroxy-2-phenylethynyl)-dibenzo-18-crown-6 was carried out, a system of linear equations was compiled using the matrix method. The average reaction rate and the optimum of the mathematical model were determined, and the experimental and calculated …


Understanding The Photodegradation Mechanism Of Gaseous Acetaldehyde Over Bi2wo6 – Modified Znwo4 Photocatalyst Under Uv Light Irradiation, Mirabbos Hojamberdiev, Ronald Vargas, Shahlo Daminova, Zuhra Kadirova Feb 2022

Understanding The Photodegradation Mechanism Of Gaseous Acetaldehyde Over Bi2wo6 – Modified Znwo4 Photocatalyst Under Uv Light Irradiation, Mirabbos Hojamberdiev, Ronald Vargas, Shahlo Daminova, Zuhra Kadirova

CHEMISTRY AND CHEMICAL ENGINEERING

Indoor air quality has a significant impact on human health as people spend more time indoors. As a common indoor air pollutant, acetaldehyde is considered toxic when exposed to it for a prolonged period. The aim of this study is the enhancement of the photocatalytic activity of ZnWO4 with a monoclinic wolframite structure for degradation of gaseous acetaldehyde by modifying its surface with Bi2WO6 layered structure. The mechanisms behind the enhanced photocatalytic activity and the pathways for acetaldehyde photodegradation over the Bi2WO6-modified ZnWO4 photocatalyst are discussed.


Modelling Of Reаctive Distillаtion Process For Etherificаtion Reаction, Adham Norkobilov, Olimjon Mаksudov, Abdulaziz Bаkhtiyorov, Orifjon Zаripov, Abbos Elmаnov Feb 2022

Modelling Of Reаctive Distillаtion Process For Etherificаtion Reаction, Adham Norkobilov, Olimjon Mаksudov, Abdulaziz Bаkhtiyorov, Orifjon Zаripov, Abbos Elmаnov

CHEMISTRY AND CHEMICAL ENGINEERING

А reаctive distillаtion system is exаmined to produce for the production of Ethyl tert butyl ether (ETBE) viа etherificаtion of isobutene with ethаnol. Optimizаtion methods using heаt integrаtion аre аlso conducted. The molаr reflux rаtio аnd reboiler duty аre cаlculаted using sensitivity аnаlysis. The bottom streаm with the sаtisfied purity of ETBE is integrаted for heаting the feed streаm to the column. Heаt integrаtion from reаctor heаt to the initiаl feed streаm аnd from bottom streаm of the column to the column inlet streаm with the purpose of аchieving tаrget feed temperаture leаds to high conversion in the reаctive distillаtion …


Synthesis And Research Of Silicon-Containing Phthalocyanine, Dilmurod Shukurov, Hayit Turayev, Abdulakhat Djalilov, Masud Karimov Oct 2021

Synthesis And Research Of Silicon-Containing Phthalocyanine, Dilmurod Shukurov, Hayit Turayev, Abdulakhat Djalilov, Masud Karimov

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this study is to synthesize, and study a new form of dye based on phthalocyanine, a silicon-containing phthalocyanine pigment used as a dye for dye-sensitive solar cells, which are currently third generation solar cells as one of the energy source alternatives. To achieve this goal, a silicon-containing phthalocyanine pigment containing urea, phthalic anhydride and sodium fluorosilicate was synthesized and studied. Based on the results of IR spectroscopy, the reaction of pigment formation is proposed and the data of scanning electron microscopy is presented. Its differential thermal analysis, photodynamic analysis and its relationship with inorganic and organic solvents …


Synthesis Of Aromatic Acetylene Alcohols Using Complex Catalytic Systems, Odiljon Ziyadullaev, Guzal Otamukhamedova, Abduvakhab Ikramov, Saida Abdurakhmanova, Otabek Boytemirov May 2021

Synthesis Of Aromatic Acetylene Alcohols Using Complex Catalytic Systems, Odiljon Ziyadullaev, Guzal Otamukhamedova, Abduvakhab Ikramov, Saida Abdurakhmanova, Otabek Boytemirov

CHEMISTRY AND CHEMICAL ENGINEERING

Some cyclic ketones (cyclopentanone, cyclohexanone, 2-methylcyclohexanone, menthol, camphor and adamantanone) enantioselective alkynylation reactions with phenylacetylene have been studied in the presence of complex catalytic systems - Zn(OTf)2/NЕt3/MeCN, 3,3′-Ph2BINOL-2Li/TGF and BuLi/KOtBu/TGF. Synthesis were performed new aromatic acetylene alcohols – 1-(2-phenylathinyl) cyclopentanol (1), 1-(2-phenylethinyl)cyclohexanol (2), 2-methyl-1-(2-phenylethinyl)cyclohexanol (3), 2-isopropyl-5-methyl-1-(2-phenylethinyl)cyclohexanol (4), 1,7,7,-trimethyl-2-(2-phenylethinyl)bicyclo [2.2.1] heptanol-2 (5) and 2-phenylethinyltricyclo [3,3,1.03,7]nonanol-2 (6). Synthesis reactions of aromatic acetylene alcohols, activation energies were determined, kinetic of chemical changes and reaction mechanisms were proposed. The course of the reactions and the effect of the selected ketone molecule size, structure and …


Heterogeneous Catalytic Conversions Of Acetylene, Abduvakhab Ikramov, Sevara Kholikova, Noryigit Musulmanov May 2021

Heterogeneous Catalytic Conversions Of Acetylene, Abduvakhab Ikramov, Sevara Kholikova, Noryigit Musulmanov

CHEMISTRY AND CHEMICAL ENGINEERING

The reactions of interaction of acetylene with water vapor, acetic acid and ammonia in the presence of heterogeneous catalysts have investigated. Depending on the nature of the starting components used, acetaldehyde and acetone, vinyl acetate, pyridine bases and pyrrole synthesized. Heterogeneous catalysts selected for each studied reaction based on some scientific prerequisites for the selection of catalysts. Active catalysts for the investigated reactions were determined, which contain compounds of cadmium, zinc, bismuth, chromium, iron and copper, in general, d-group metals. γ-Al2O3, bentonite and kaolin used as a catalyst carrier. Hydrofluoric acid, acetic acid, ammonium fluoride and …


Synthesis Of Some N-Oxides Of Pyridylacethylene Amines Based On 2-Methyl-5-Ethynylpyridine, Abduvakhab Ikramov, Odiljon Ziyadullayev, Adkham Khamidjanov, Shavkat Bojariev, Davron Khandamov Apr 2021

Synthesis Of Some N-Oxides Of Pyridylacethylene Amines Based On 2-Methyl-5-Ethynylpyridine, Abduvakhab Ikramov, Odiljon Ziyadullayev, Adkham Khamidjanov, Shavkat Bojariev, Davron Khandamov

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this work is to study the reaction of 2-methyl-5-ethynylpyridine N-oxide with some aliphatic and aromatic amines to obtain N-oxides of pyridylacetylenic amines. 2-Methyl-5-ethylpyridine converted to 2-methyl-5-vinylpyridine by dehydrogenation, and 2-methyl-5-ethynylpyridine obtained by bromination and dehydrobromination. 2-methyl-5-ethynylpyridine N-oxide synthesized by oxidation of 2-methyl-5-ethynylpyridine with perhydrol in acetic anhydride. The synthesis of N-oxides of pyridylacetylenic amines by the Mannich reaction carried out. The effect of the solvents: methanol, ethanol and n-dioxane, the catalyst, and the reaction time on the yield of the final product studied. The structure and composition of the synthesized PAA N-oxides were established using IR and …


The Role Of Hydrogen Bonds In Diluted Ethanol Solutions Of Cyclohexane And Dimethylformamide, Dilbar Bozorova, Shukur Gofurov, Mavlonbek Ziyayev, Dildora Mirtojiyeva, Odina Ismanova, Oksana Ismoilova Apr 2021

The Role Of Hydrogen Bonds In Diluted Ethanol Solutions Of Cyclohexane And Dimethylformamide, Dilbar Bozorova, Shukur Gofurov, Mavlonbek Ziyayev, Dildora Mirtojiyeva, Odina Ismanova, Oksana Ismoilova

CHEMISTRY AND CHEMICAL ENGINEERING

The refractometric method and Fourier transform infrared spectroscopy were used to determine the optical features of the concentration characteristics of diluted ethanol solutions of cyclohexane and dimethylformamide. It was found for the first time that at some concentrations the hydrogen bond is stronger than for a pure ethanol solution. The first maximum of the excess refractive index of solutions is formed at a concentration of 0.02 mole fraction of cyclohexane and dimethylformamide, which is in good correlation with IR spectroscopy, indicating the largest number of formed hydrogen bonds.


Ethinylation Reactions Of Some Aldehydes In The Presence Of Phenylacetylene Using High-Base Catalytic Systems, Abdurakhmanova Saida, Ikramov Abduvaxab, Ziyadullayev Odiljon, Ablakulov Lochin Feb 2021

Ethinylation Reactions Of Some Aldehydes In The Presence Of Phenylacetylene Using High-Base Catalytic Systems, Abdurakhmanova Saida, Ikramov Abduvaxab, Ziyadullayev Odiljon, Ablakulov Lochin

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the research work is the development of synthesis methods of aromatic acetylene alcohols and their various derivatives using different catalytic systems and also, determining their structure, physico-chemical and biological properties. The most effective way of synthesizing AAA is determined using selected complex catalytic systems and also, the range of catalytic activity of used catalysts is created. Acetic aldehyde, benzaldehyde and cyclohexonal, high-base catalytic systems − MOH/ДМСО∙H2O and M2CO3/ДMСO∙H2O with phenylacetylene reaction of enantioselective etynilation were investiged. Efficiency and course of chemical reaction in the process of formation acetylene alcohol affection of temperature, reaction duration, solvents, catalysts and …


Synthesis Of Meta-Altered Arylmaleinamide And Preparation Of Esters In Their Presence, Turaeva Khurshida, Yuldasheva Mukhabbat, Khaydarova Sadokat Feb 2021

Synthesis Of Meta-Altered Arylmaleinamide And Preparation Of Esters In Their Presence, Turaeva Khurshida, Yuldasheva Mukhabbat, Khaydarova Sadokat

CHEMISTRY AND CHEMICAL ENGINEERING

The development of new methods of synthesis using cheaper reagents for the preparation of maleic acid derivatives, the study of chemical properties and the determination of new directions for the practical application of maleic acid derivatives are still relevant. Therefore, the development of this work is an urgent task. The aim of this study was to obtain the synthesis of monomaleinamide compounds under various conditions to obtain arylmaleimide derivatives of maleic acid and to transfer them in a pure state for further reactions. In this study, scientific studies were carried out to find convenient methods for the preparation of monoamide …


Mixed Complex Compounds Of Palmitate, Oleate Calcium With Acetamide, Nicotinamide And Thiocarbamide, Ibadullaeva Tursunoy, Azizov Tokhir, Ibragimova Мavluda Dec 2020

Mixed Complex Compounds Of Palmitate, Oleate Calcium With Acetamide, Nicotinamide And Thiocarbamide, Ibadullaeva Tursunoy, Azizov Tokhir, Ibragimova Мavluda

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of the study was the synthesis and study of the structure of mixed complexes of palmitate, calcium oleate with acetamide, nicotinamide and thiocarbamide. The mixed coordination compounds of palmitate and calcium oleate were synthesized. The composition, individuality, thermal behavior, methods of coordinating the palmitate and oleate fragments, acetamide, nicotinamide and thiocarbamide molecules have been established. Comparison of the diffraction patterns of calcium palmitate and oleate, free ligand molecules and synthesized compounds showed the mismatch of the diffractograms, conseqently that the synthesized complexes have an individual crystal lattice different from the starting materials. The method of coordination of amide …


Synthesis Of Esters Of Halogenoacetic Acids, Yuldasheva Muxabbat, Turaev Sherzod Dec 2020

Synthesis Of Esters Of Halogenoacetic Acids, Yuldasheva Muxabbat, Turaev Sherzod

CHEMISTRY AND CHEMICAL ENGINEERING

Amidoalkylating reagents containing a phthalimide group are used in the synthesis of hard-to-reach primary amines and complex heterocyclic compounds. These types of amidoalkylating compounds are suitable reagents for nucleophilic substituted reactions in acidic media due to their resistance to acids. Result of reactions of amidoalkylating reagents-N-hydroxyethylphthalimide and N-hydroxymethylphthalimide with aliphatic carbonic acids can also produce new bactericidal and fungicidal esters. In this study, halogen acids reacted with N-hydroxymethylphthalimide monochloric acetic acid, monobromic acetic acid, monoiodic acetic acid, trifluoric acetic acid and trichloroacetic acid, as well as, N-b-hydroxyethylphthaleidyl monohydric acid. As a result of the reactions, new phthalimidomethyl and phthalimidoethyl esters …


Modification Of Inuline By Iodic Acid, Rakhmanberdiyev Gappar, Ibragimova Кomila, Аxmedov Оliy Oct 2020

Modification Of Inuline By Iodic Acid, Rakhmanberdiyev Gappar, Ibragimova Кomila, Аxmedov Оliy

CHEMISTRY AND CHEMICAL ENGINEERING

In order to further modify inulin with drugs, the process of introducing reactive aldehyde groups into the inulin macromolecule was carried out. Aldehyde groups were introduced by oxidizing inulin with iodic acid. The process of oxidation of inulin and cellulose with iodic acid was compared. The quantities of aldehyde groups in the oxidized samples were estimated, their molecular weights were determined, IR spectra were measured, the iodine number of the inulin dialdehyde and their oxidation state were determined.


Synthesis Of 1,2,3-Triazoles Based On Propargyl Ethers Of Carbamate, Djuraev Abdukahhor, Yakubxodjaeva Malika, Ataxodjaeva Matluba, Gaibullaev Oibek Oct 2020

Synthesis Of 1,2,3-Triazoles Based On Propargyl Ethers Of Carbamate, Djuraev Abdukahhor, Yakubxodjaeva Malika, Ataxodjaeva Matluba, Gaibullaev Oibek

CHEMISTRY AND CHEMICAL ENGINEERING

By the interaction of propargyl esters of carbamate derivatives with phenylazide, 1,2,3- triazole derivatives were synthesized. Their anti-inflammatory activity was subsequently studied.During the study of biological activity, a relationship was established between the anti- inflammatory activity and the chemical structure in the studied series of 1,2,3-triazole derivatives.


The Research Of Conditions For The Formation Of Phenol Formaldehyde Resins Modified With Hydroxyl Containg Polyether Polyol, Magrupov Farkhad, Umarov Sherali, Tohirov Murodjon, Radjabova Zukhra Oct 2020

The Research Of Conditions For The Formation Of Phenol Formaldehyde Resins Modified With Hydroxyl Containg Polyether Polyol, Magrupov Farkhad, Umarov Sherali, Tohirov Murodjon, Radjabova Zukhra

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the study was to study the conditions of copolycondensation of phenol alcohol with hydroxyl-containing polyether polyol in the presence of maleic anhydride chain extender in order to obtain modified thermoset phenolic-formaldehyde oligomers. Investigation of the dependence of the content of free phenol, formaldehyde and methylol groups on time during the synthesis of the modified phenol-formaldehyde resin with the ratios hydroxyl-containing polyether polyol:phenol alcohol 1:60 mol/mol and 1:100 mol/mol. It was revealed that maleic anhydride, present in the reaction medium as a copolycondensation catalyst, also participates in copolycondensation reactions as a chain extender. Moreover, as the molar fraction …