IR Spectrometric Analysis Research Articles

Investigation of the Process of Agglomeration of Phosphorites Using Phosphate-Siliceous Shales and Oil Sludge

Introduction This article aims to discuss the physico-chemical features of the agglomeration process of phosphorus fines using phosphate-siliceous shales and oil sludge. Methods The composition and structure of the starting materials and physico-chemical transformations under thermal influence are studied using IR spectrometry and differential thermal analysis methods. Results The results of IR spectrometric analysis of the phosphate siliceous shales are characterized by intense peaks at 493.78, 547.78, and 678.94 cm-1, corresponding to Ca-O-P compounds. Moreover, the wave oscillations in the region of 837.11-995.27 cm-1 indicate the characteristics of Si-O valence bonds, and in the region of 1114.86-1431 cm-1 depict the characteristics of Si-O-Al compounds. The IR spectrum of oil sludge is characterized by the presence of wave oscillations in the region of 1411.89-2904.80 cm-1 corresponding to petroleum components. Conclusion The differential thermal analysis of the investigated sample of phosphate-siliceous shale does not have intense endo- and exo-effects, and it is characterized by a significant predominance of hydrate compounds of aluminosilicate and carbonate components.

ИССЛЕДОВАНИЕ ФИЗИКО-ХИМИЧЕСКИХ И ПРОТИВОИЗНОСНЫХ СВОЙСТВ МОТОРНЫХ МАСЕЛ ПО ЗАВЕРШЕНИИ ПРОЦЕССА ЭКСПЛУАТАЦИИ

There is given the study of viscous properties of engine oil, depending on the temperature before and after change on modern domestic gasoline and diesel cars, the determination of spectral characteristics and X-ray fluorescence analysis of wear particles after mileage. The degree of viscosity of semi-synthetic oils of two types is estimated. The oils were cooled and heated up to 150 °C. A digital viscometer was used, the dynamic viscosity of all oils decreased with increasing temperature, which is associated with oxidation in waste oil. To assess the effect of motor oil on engine operation, IR spectrometric analysis is performed and the thickness of the lubricating film is determined. The test results showed a qualitative and quantitative change in the characteristic frequencies of the new engine oil and the spent one after 10,000 km. X-ray fluorescence analysis makes it possible to analyze wear products and determine which mechanism in the engine is most susceptible to wear. Lines have characteristic absorption frequencies and indicate a change in physico-chemical properties of oil in the engine. An increase in contamination and in the viscosity of used oils is associated with the presence of impurities formed during the oxidation and polymerization of the base oil. It is necessary to increase the number of samples and sampling during different periods of operation so that you can verify the same effect throughout the entire engine operation. The results obtained indicate that these methods can be used to analyze and control the mode of operation of oils in the engine, allowing to determine the wear and further apply appropriate additives to the oil to improve performance properties.

Influence of the black seed oil modified epoxy resin/biscycloaliphatic epoxide monomer weight ratio on thermal properties of photocrosslinked coatings

AbstractThe influence of the black seed oil modified epoxy resin (EBSO)/monomer 3,4‐epoxycyclohexylmethyl 3,4‐epoxycyclohexane carboxylate (BCDE) weight ratio in the coatings based on the compounds and photoinitiator triarylsulfonium hexafluoroantimonate (TAS) on thermal properties of photocrosslinked coatings have been studied. The chemical structure of investigated UV‐cured coatings was characterized by IR spectrometric analysis. Their thermogravimetric (TG) and differential scanning calorimetry (DSC) behavior were determined by TG and DSC analysis, respectively. It was shown that the testing atmosphere had almost no effect to the form of TG, DTG curves and little effect on value of weight degradation of investigated coatings. The volatilization of low molecular weight compounds was observed in the range from room temperature to 360oC while the thermal degradation of the coatings occurred in the range from 360 to 455.5oC. The augmentation of the EBSO/BCDE weight ratio from 20/80 to 80/20 led to an increase of the degradation temperatures in the nitrogen atmosphere; extreme character of weight loss variation as well as the reduction of glass transition temperatures of the coatings from 79.8oC (Tg1) and 83oC (Tg2) to 36.8 (Tg1) and 38.9oC (Tg2), correspondingly.

Obtaining phosphate fertilizer with additional nutrients

In order to obtain phosphorus fertilizer enriched with additional nutrients, the decomposition process of apatite concentrate with sulfuric acid was carried out with an additive, in the first variant – ammonium hydrophosphate, and in the second variant - ammonium and potassium hydrophosphates. Experimental studies have studied the effect of additives on the interaction of sulfuric acid with fluorapatite, as well as X-ray phase and IR spectroscopic analyses have studied the structural composition of the resulting product. It was found that with the use of additives, the resulting phosphorus fertilizer contains, along with calcium dihydrophosphate, also ammonium dihydrophosphate. A distinctive feature is the decomposition of sulfuric acid phosphates, resulting in a poorly soluble calcium sulfate that passes into the solid phase, which has traces of its presence in the resulting fertilizer, and may also not be part of the solution. The process of decomposition of fluorapatite with sulfuric acid using an additional part (NH4)2HPO4, the optimal amount of the additional part should be considered 12-18% (by weight of sulfuric acid) additive, while the highest degree of decomposition of apatite concentrate is achieved, which is 95-97%. The conducted studies have established that the introduction of an additive - ammonium and potassium hydrophosphates - into the process of sulfuric acid decomposition of apatite concentrate also has a positive effect on the duration of the superphosphate maturation period. To clarify the structural composition of the finished product, X–ray phase studies and IR spectrometric analysis of the powdered product were carried out. Thus, mineral fertilizers obtained with the use of additives having an additional nutrient element in their composition, namely nitrogen - in the first variant, and nitrogen and potassium - in the second variant.

Modification of polyvinyl alcohol by ozonated oxidation in an aqueous solution

Currently, the task of obtaining polyvinyl alcohol oligomers (PVA) is urgent to create functional materials of a new generation with specified properties. One of the methods of modification of PVS is ozonolysis, which has a number of advantages over other methods of oxidative degradation of polymers. The aim of the work is to evaluate the structural changes and physico–mechanical characteristics of film samples of PVS modified by ozonated oxidation. To carry out the oxidation process, a 5% aqueous solution of PVA brand 1799 was prepared. The ozone-oxygen mixture was obtained using an ozonizer of a known design. The oxidation of PVS was carried out in a glass thermostatically controlled flask at 70 ° C, blowing an ozone-oxygen mixture through an aqueous solution of PVS for 40 minutes. Sampling was carried out after 10, 20 and 40 minutes of oxidation. The films were obtained by irrigation followed by air drying, after which they were subjected to IR spectrometric analysis and strength indicators were determined. As a result of the study, it was found that the modification of PVA brand 1799 by ozonated oxidation in an aqueous medium is accompanied by the following change in IR spectrograms: in the region of 1400 - 1600 cm-1, a sharp decrease in the intensity of the peak corresponding to hydroxyl groups forming hydrogen bonds is observed for ozone-oxidized PVA, in the region of 1650 – 1700 cm-1, a pattern of decrease in intensity is noted the peak with an increase in the oxidation time of PVA with ozone, which indicates a decrease in the MM of the polymer as a result of oxidative degradation, in the region of 3400 – 3600 cm-1 marked a change in the nature of the spectrogram, which also indicates a change in the structure of hydrogen bonds in oxidized PVS; the physico-mechanical properties of film samples subjected to 40-minute ozonated oxidation of PVS change towards a decrease in both strength and elongation at break by an average of 4 times, the Young's modulus decreases by more than 3 times, and the stretching diagram changes character in the zone of highly elastic deformation (the intensity of stress growth decreases by 1.5-2 times as the film elongates during stretching) and the fracture zone (the diagram acquires a stepwise character without a sharp break), which is associated with a decrease in the molecular weight of the PVS, the acquisition of new functional groups, a change in the stereoregularity of the hydroxyl groups of the main polymer chains, an increase in amorphousness and a change in their relaxation time.

Analysis of the mineralogical composition of soil samples: Case study of Karmana district

This article deals with the issues of determining the mineralogical composition of soil samples in the city of Navoi and the Karmaninsky district (the settlement of Khazora, 24 km from the city) and identifying the degree of salinization of these old irrigated soils in the region. To determine the mineralogical composition of soil soils, the X-ray diffraction method of research was used, and to determine the functional groups of carbon, sulfur, and chlorine, IR spectrometric analysis of samples was used. The studies carried out made it possible to establish a carbonate type of salinity for the city of Navoi, and for the Karmaninsky district, the dominance was noted first of carbonate - 45.4%, then sulfate 28.8%, and only lastly did the third type of salinity appear, represented by chloride - 0.8%, found on the surface layer of the soil (0-0, mm).

THE EFFECT OF ADDITIVES CONTAINING POLYCYCLIC ARENAS ON THE FORMATION OF THE PROPERTIES OF BITUMEN BINDER IN THE PROCESS OF THEIR JOINT OXIDATION WITH OIL TAR

The results of the study of the effect of polycyclic aromatic hydrocarbons (PAHs) on the efficiency of the process of oxidation of oil tar into bitumen are presented. By-products of oil refining were used as additives to tar: the residue of heavy pyrolysis resin (OTSP) and 2 samples of extracts (MAE-1; MAE-2) isolated from extracts of selective purification of oil distillate VD-3 using a polar solvent N-methylpyrrolidone containing 10 wt.% ethylene glycol. One of the extracts, MAE-2, was obtained from an oil extract pretreated with microwave radiation. Additives were injected into the tar at 70 ℃ in an amount of 10 wt.%. The hydrocarbon system was oxidized with air oxygen for 6 hours at a temperature of 220 ℃. Based on the analysis of the properties and group, structural and group compositions of oxidized bitumen binders, it was found that the content of benzene resins in the binder increases (~ 2.5 times) and asphaltenes (by 3 wt.%) during the oxidation of the mixture of MAE-1 + OTSP. When the mixture of MAE-2 + OTSP is oxidized, the content of benzene resins and asphaltenes in the binder decreases. The observed changes in the compositions of the oxidation products of mixtures of MAE + OTSP are preserved during the oxidation of tar + systems (MAE + OTSP). At the same time , the conditional content of aromatic structures according to the data of the IR spectrometric analysis in the oil component of the oxidized tar + system (MAE-2+OTSP), as well as poly-substituted polycyclic aromatic structures, is almost 2 times higher than for the oil component of the oxidized tar + system (MAE-1+OTSP). As a result, the oxidation of tar mixtures with additives containing polycyclic arenas improves the quality of the target product by increasing the content of asphaltenes and aromatic structures in the aromatic oil component.

Determination of the total content of aromatic hydrocarbons by Fourier-transform IR spectroscopy in the products of diesel hydrofining

A comparative analysis of current methods for determination of aromatic hydrocarbons in the components of diesel fuel revealed that IR spectrometry appeared to be the most optimal method for operational control of the content of aromatic hydrocarbons in medium distillate products of the hydrogenation process. We developed a procedure for quantitative determination of aromatic hydrocarbons in the components of diesel fuel using IR Fourier spectroscopy. The analysis of absorption spectra of the components of diesel fuel revealed that the optical density of the stretching vibration band of the aromatic ring is proportional to the quantitative content of aromatic hydrocarbons (AHC) in the components of diesel fuel. One of the components for compounding diesel fuels obtained at JSC «ANKhK» during hydrotreating of raw materials under severe conditions (30 MPa, 380 – 400°C) was selected as an object of the study. Conditions of IR spectrometric analysis (wave number — 1606.5 cm–1, cell material — NaCl, absorbing layer thickness — 0.1 cm) were specified after recording of the absorption spectrum of the purified component. To construct a calibration dependence the total AHC content and corresponding optical density of the sample were determined by the methods of HPLC and IR spectrometry, respectively. The samples of hydrogenate under study (taken at different timepoints) contained 1 – 8% AHC on average depending on the parameters of a continuously operating unit. The characteristics of the proposed procedure were evaluated in accordance with the requirements of RMG 76–2014. The correctness of the obtained results of AHC determination was confirmed in comparison with the data of independent (tetrimetric) analysis. The use of the developed method in analysis of other components of diesel fuel, requires additional studies to determine the interfering substances and assess their impact on the accuracy of AHC determination.

Solubilization and functionalization of sulfuric acid lignin generated during bioethanol production from woody biomass

Sulfuric acid lignin (SAL), which is formed as a by-product during the production of bioethanol from woody biomass, was solubilized and functionalized by hydrothermal reaction. SAL could be easily dissolved in an alkaline medium, especially sodium hydroxide solution, by this reaction. The soluble part of the reaction products (S-HSAL) could be dissolved at neutral pH. IR spectrometric analysis of SAL revealed that hydrophilic groups were introduced in it during the reaction. The dispersibility of S-HSAL was increased by sulfonation (SS–HSAL), and it was found to be an effective dispersant for gypsum paste.

Determination of oxygen and carbon impurities in polycrystalline silicon by IR spectrometry

The possibility of using infrared spectrometry for the determination of the total oxygen and carbon impurity in polycrystalline silicon of the natural isotope composition and that enriched with the 28Si isotope was studied for samples synthesized by different methods. The results of determining these impurities by the optical method are compared to those obtained by independent methods of analysis. The conditions of IR spectrometric analysis of the silicon synthesized by deposition from the gas phase are determined. It is shown that, for IR spectrometry, the upper boundaries of the analytical range of oxygen and carbon in polycrystalline silicon are 1 × 1018 and 2 × 1018 cm−3; and the limits of their detection are 8 × 1015 and 5 × 1015 cm−3 at a sample thickness of 0.5 and 0.2 cm, respectively.

Comparative study of pyrolytic decomposition of polymers alone or in EVA/PS, EVA/PVC and EVA/cellulose mixtures

The behavior of mixtures of EVA–PS, EVA–PVC and EVA–cellulose in various proportions were investigated under pyrolysis. A kinetic model with an independent pathway is proposed for the weight loss and compared with the experimental and theoretical results obtained in a previous study with individual polymers. The kinetic parameters were determined and online IR spectrometric analysis used to follow the evolution of the gaseous pyrolysis products versus the temperature. The result shows good agreement for the EVA–PS mixture and confirms the hypothesis of an independent pathway. However, in the case of EVA–PVC and EVA–cellulose mixtures, the polymers affect one other in the pyrolysis reaction.

Coupled DTA–TGA–FT-IR investigation of pyrolytic decomposition of EVA, PVC and cellulose

The behavior of individual polymers (EVA, PS, PVC and cellulose) was investigated under pyrolysis at different heating rates. A kinetic model is proposed for the weight loss and compared with the experimental results and the kinetic parameters were determined and compared with the available published data. IR spectrometric analysis was used to follow the evolution of the gaseous pyrolysis products versus the temperature. Analysis of online FT-IR spectra confirmed the initial loss of acetic acid for EVA and one HCl for PVC.

Simple, rapid and inexpensive diagnosis of H. pylori infection in 13C-urea breath test: IR spectrometric analysis : Y. Goto, Y. Ogihara, Y. Taniguchi∗, K. Satoh∗, K. Kimura∗, K. Takatori#, K. Iida# and M. Kajiwara#. Exploratory Res. Lab. III, Daiichi R & D center, Tokyo, ∗Dept. Gastroenterol., Jichi Med. School & #Dep. Med. Chem., Meiji College of Pharm., Tokyo, Japan

Simple, rapid and inexpensive diagnosis of H. pylori infection in 13C-urea breath test: IR spectrometric analysis : Y. Goto, Y. Ogihara, Y. Taniguchi∗, K. Satoh∗, K. Kimura∗, K. Takatori#, K. Iida# and M. Kajiwara#. Exploratory Res. Lab. III, Daiichi R & D center, Tokyo, ∗Dept. Gastroenterol., Jichi Med. School & #Dep. Med. Chem., Meiji College of Pharm., Tokyo, Japan

Influence of Stabilizers with Secondary Amine Groups on the Thermal and Thermoxidative Decomposition of Polyepichlorohydrin

Abstract The thermal and thermoxidative destruction of epichlorohydrin elastomers, stabilized with secondary amine groups containing antioxidants has been studied, using TG and DSC methods, chromatographic and IR-spectrometric analysis of gaseous products of the destruction and also elementary analysis, gel-content and viscometric measurements on the polymers. The elimination of chlorine atoms is not important in the process of polyepichlorohydrin destruction. Most important are the scission of the main chains, producing drastic decreases of the intrinsic viscosities of the polymers, and also the formation of carbonyl groups on the macromolecules. The first destruction step is accompanied by substantial changes of the molecular weights, the weight loss being not important. The secondary amine-type stabilizers do not influence the thermal destruction, but have a good inhibiting activity on the thermoxidative destruction of polyepichlorohydrin, increasing the temperature at which this process occurs. At rel...

A study on the electrochemical polymerization of polyparaphenylene using benzene and biphenyl as starting material

Polymer films of poly-p-phenylene (PPP) were electrochemically synthesized using both monomer (benzene) and dimer (biphenyl) as starting material in Li- or tetrabutylammonium-tetrfluoroborate or tetrabutylammonium-perchlorate (0.1 M) in different solvents. Polymerization was performed either potentiostatically or galvanostatically using both anodic and cathodic polarization of the working electrode in a three-electrode one-compartment cell. ITO-glass, Pt, GC and Au were used as electrode material. Electrochemical properties of the PPP-films were studied by cyclic voltammetry and characterized by ir-spectrometric analysis. The thickness of the films were estimated from the charge consumed during polymerization. The role of different parameters in the electrosynthesis of the PPP-films was studied and the electrochemical behaviour of the films thus obtained was compared with each other. Using biphenyl as starting material the film was formed easier due to its lower oxidation potential. Ir-spectrometric analysis showed that the product with both starting materials consists of both para- and ortho-linked monomer units. It was also possible to grow PPP-films by cathodic polymerization.

DETERMINATION OF SEVERAL PHYSICAL PROPERTIES OF LIGHT PETROLEUM PRODUCTS USING IR

In the present study IR spectrometric analysis was used to determine clear research octane number, heat of formation, specific gravity and mole fraction of methyl group, simultaneously in hydrocarbon mixtures. IR absorption spectrum can be used to provide information, that can be obtained by several existing test methods.

THERMAL DEGRADATION AND WATER SORPTION FOR α-PYRROLIDONE/ε-CAPROLACTAM COPOLYMER

Thermal degradation and water sorption were investigated for the copolymers (4/6 copolymers), which had been prepared by anionic copolymerization of α-pyrrolidone and e-caprolactam, in comparison with those of nylon 4, 6 and blends. The compositions of 4/6 copolymers were determined by IR spectrometric analysis. The water sorption isotherms were obtained by a weighing bottle method at various water vapor pressures controlled with saturated salt solutions.The rates of thermal degradation for 4/6 copolymers at 275°C (3mm Hg, N2) were somewhat smaller than those for nylon 4 and blends in the range of weight loss less than the amount of nylon 4 component. The amount of water sorbed in a monolayer state (Vm) obtained by BET plot, and the molar ratio of Vm to the amide content in amorphous region (Vm/(CONH) (1-α), α: crystallinity) for nylon 4 were about 2 and 1.5 times, respectively as large as those for nylon 6. As to 4/6 copolymers, Vm/(CONH) (1-α) increased linearly with the composition of nylon 4. From the analysis using the cluster function, it was elucidated that the formation of cluster in sorbed water molecules began to arise at a higher moisture regain for nylon 4 than for nylon 6, and the behavior in cluster formation for 4/6 copolymer having the composition 23.2 mole-% nylon 4 was rather similar to that of nylon 4, because of the increase of free amide groups caused by the decrease of crystallinity.Although there are some problems in a low molecular weight and a low crystallinity, the 4/6 copolymer is interesting from the view point of melt process (spinning), because of their high moisture regain and melting point of about 150°C at which the polymer chain of nylon 4 is thermally stable.

Zur Elektronen-Strahlenchemie des Radikalfängers Diphenylpikrylhydrazyl in Methyljodid (I) / Electron-radiation Chemistry of the Radical Scavenger 1,1-Diphenyl-2-picrylhydrazyl in Methyl Iodide

The radical scavenger 1,1-diphenyl-2-picrylhydrazyl (DPPH) in methyl iodide solution was exposed to electron-rays in the absence of air, and the products were separated by thin-layer chromatography. The substances were characterised and identified as 1,1-diphenyl-2-picrylhydrazine (1), p-nitro-diphenylamine (2), 2,6-dinitro-diphenylamine (3), 1-phenyl-1-(p-nitrophenyl)-2-picrylhydrazine (4), and 2,4,6-trinitro-aniline (5). In addition some unidentified products are formed. The mass- and ir-spectrometric analysis of the low molecular weight products indicates that they are produced by the splitting of the N — N-bond in the DPPH molecule. From the material balance and the chemical compositions of the reaction products, it is presumed that the early stage of the decomposition of DPPH induced by electron-rays is a nitration of DPPH. A mechanism is formulated to explain the formation of the compounds.

Die Strahlenchemie des Hexachlorbutadiens / The Radiation Chemistry of Hexachlorobutadiene

Hydrogen chloride, cyclohexylchloride and the new compound C4Cl5-C6H11 (cyclohexylpentachlorobutadiene) are formed when mixtures of hexachlorobutadiene and cyclohexane are exposed to γ-radiation or 2 MeV-electrons from an accelerator. The mass- and IR-spectrometric analyses of the new product indicate that the C6H11-group is bound mainly to a primary C-atom of the hexachlorobutadiene. The 100 eV-yield of C4Cl5- C6H11 is of the order of 3.3 ± 0.15 molecules/100 eV. Because hexachlorobutadiene is a by-product in the technical synthesis of chlorine containing hydrocarbons' new reactions of this compound could be of industrial importance. A mechanism is formulated to explain the formation of the products.