Effect Of Peptization Research Articles

ИССЛЕДОВАНИЕ ВЛИЯНИЯ ФОРМИАТА НАТРИЯ НА ТЕРМОСТОЙКОСТЬ КРАХМАЛСОДЕРЖАЩЕГО ГЛИНИСТОГО БУРОВОГО РАСТВОРА

Актуальность работы обусловлена необходимостью сохранения свойств буровых растворов, содержащих крахмальные реагенты, в условиях высокой минерализации и длительного воздействия повышенных температур. Цель: экспериментально определить температурный интервал и оптимальные концентрации эффективного применения формиата натрия в составе буровых растворов, содержащих крахмальные реагенты. Объекты: крахмалсодержащий глинистый буровой раствор с разными концентрациями натриевых солей (хлорида натрия и формиата натрия). Методы: определение фильтрационных и реологических параметров согласно ГОСТ 33213-2014 (ISO 10414-1:2008) после старения буровых растворов при повышенных температурах с использованием термоячеек; проведение опытов методом построения матрицы центрального композиционного планирования и математической обработки результатов экспериментальных данных. Результаты. Проведен сравнительный анализ свойств глинистых буровых растворов, содержащих крахмальный реагент, с использованием хлорида натрия NaCl и формиата натрия HCOONa, после длительного нахождения системы в условиях высоких температур. Показано, что природа соли оказывает значительное влияние на термостойкость крахмалсодержащего бурового раствора: хлорид натрия не обеспечивает термостабильности раствора; формиат натрия позволяет обеспечить термостойкость крахмалсодержащего бурового раствора до 140–160 °С. Получены уравнения регрессии второго порядка, описывающие зависимость показателя фильтрации и реологических параметров крахмалсодержащего глинистого бурового раствора от температуры и концентрации формиата натрия. Установлено, что термостойкость крахмального реагента при совместном применении с формиатом натрия повышается вследствие высокой растворимости соли, которая подавляет гидратацию полисахарида и, соответственно, замедляет его гидролиз при воздействии высоких температур. Выявлено, что эффективная концентрация натриевой соли муравьиной кислоты как термостабилизатора в составе крахмалсодержащего бурового раствора зависит от температуры применения системы: при низких концентрациях соли термостойкость обеспечивается в диапазоне 100–133 °С за счет хорошей активности крахмала; при высоких концентрациях соли – в диапазоне 133–160 °С – за счет низкого содержания свободной воды в системе вследствие высокой растворимости формиата натрия. Показано, что формиат натрия не предотвращает набухание глин, а наоборот, способен оказывать на них пептизирующее действие.

Improving recycled asphalt using sustainable hybrid rejuvenators with enhanced intercalation into oxidized asphaltenes nanoaggregates

This paper introduces a new bio-rejuvenator made from a blend of high-protein algae and high-lipid animal manure and studies its interaction with aged bitumen molecules to revitalize aged asphalt. True revitalization requires restoring not only the chemical balance but also the molecular conformation. Therefore, rejuvenators should be able to de-agglomerate oxidized asphaltenes while compensating for components that are lost during aging. This study uses a balanced feedstock to control the composition and concentration of active molecules in a rejuvenator to increase its efficiency. To do so, a balanced combination of high-protein algae and high-lipid manure were used to synthesize bio-rejuvenator having different concentration of straight chain hydrocarbons and aromatic compounds, with the former helping to restore chemical balance, and the latter working to de-agglomerate oxidized asphaltene. This in turn can restore aged bitumen's molecular conformation, leading to restoration of its physicochemical and rheological properties. The study results showed that bio-rejuvenator produced from the algae-manure balanced feedstock was more effective rejuvenator than using either of algae or manure solely. The superiority of rejuvenator made by co-liquefaction of a balanced feedstock verified by comparing its dosage efficiency with that of its counterparts made from isolated bio-mass sources. The comparison was done based on the extent of increase in crossover modulus and crossover frequency of an aged bitumen doped with a constant dosage of each rejuvenator with co-liquified scenario showing a much higher increase than other scenarios. Molecular dynamics simulation results revealed that latter bio-rejuvenator’s molecules have a peptizing effect on oxidized asphaltene molecules leading to a significant decrease in the radial distribution function of oxidized asphaltene molecules restoring their molecular conformation. This in turn leads to revitalizing aged asphalt physio-chemical properties to enable reuse and recycling of aged asphalt composites and improve recycling of asphalt pavements to promote sustainability.

Effect of peptization of an inorganic sorbent on its sorption characteristics

A series of samples of Termoxid-35 inorganic sorbent (nickel ferrocyanide applied onto zirconium hydroxide granules) were prepared. The samples have similar chemical composition but differ in the degree of peptization in aqueous solutions. Kinetic curves of 137Cs sorption from aqueous solution demonstrate relationship between the sorbent tendency to peptization and its sorption properties. With an increase in the peptizability of the sorbent, its sorption-selective properties become considerably worse. The sorbent preparation process should involve treatment procedures allowing preparation of the peptization-resistant material.

A mechanochemical approach to get stunningly uniform particles of magnesium–aluminum-layered double hydroxides

A mechanochemical approach is developed in preparing a series of magnesium–aluminum-layered double hydroxides (Mg–Al-LDHs). This approach includes a mechanochemical process which involved manual grinding of solid salts in an agate mortar and afterwards peptization process. In order to verify the LDHs structure synthesized in the grinding process, X-ray diffraction (XRD) patterns, transmission electron microscopy (TEM) photos and thermogravimetry/differential scanning calorimetry (TG–DSC) property of the product without peptization were characterized and the results show that amorphous particles with low crystallinity and poor thermal stability are obtained, and the effect of peptization is to improve the properties, more accurately, regular particles with high crystallinity and good thermal stability can be gained after peptization. Furthermore, the fundamental experimental parameters including grinding time, the molar ratio of Mg to Al element (defined as R value) and the water content were systematically examined in order to control the size and morphologies of LDHs particles, regular hexagonal particles or the spherical nanostructures can be efficiently obtained and the particle sizes were controlled in the range of 52–130nm by carefully adjusting these parameters. At last, stunningly uniform Mg–Al-LDHs particles can be synthesized under proper R values, suitable grinding time and high degree of supersaturation.

Asphaltene Chemical Characterization as a Function of Solubility: Effects on Stability and Aggregation

Rather recently, a new technique called the “asphaltene solubility profile” was developed to analyze the stability of asphaltenes. In this technique, a distribution of the asphaltenes in terms of their respective solubilities is provided, allowing for a more comprehensive view of how the different molecules comprising asphaltenes behave and interact. In the present work, maltenes and asphaltenes are preparatively separated according to the classification established by the asphaltene solubility profile analysis, i.e., “transitional material” or easy-to-dissolve asphaltenes (EDA) and difficult-to-dissolve asphaltenes (DDA). The results obtained for blends of DDA and EDA show that the latter fraction has a peptizing effect on the former. EDA help in the solubilization of DDA, as shown by the asphaltene solubility profile of the blends, and also decreases aggregation, as shown by the size-exclusion chromatography experiments. These findings support the following: (a) the idea that this so-called “transitional fraction or EDA” plays a key role in the stabilization of asphaltenes similar to the fraction known as “resins” in the literature, (b) the use of solubility profile analysis as a valid test to evaluate asphaltene stability, and (c) the model of crude oils as a continuum of molecules in which their properties vary gradually.

Effect of peptization on texture and physicomechanical properties of aluminum hydroxides

The method of low-temperature adsorption of nitrogen was applied to study structural characteristics of commercial peptized aluminum hydroxides. An increase or decrease in the porometric volume, depending on the nature and concentration of the peptizing agent, was analyzed. The phenomena observed are explained in terms of the mechanism suggested for formation of the pore system in commercial aluminum hydroxides. The dependence of the physicomechanical properties of active aluminum oxide on synthesis conditions and texture characteristics of commercial aluminum hydroxides was studied.

Effect of peptization on phase transformation of TiO 2 nanoparticles

TiO 2 nanoparticles were prepared by direct hydrolysis method from metatitanic acid. After the resulting powders were peptized by hydrochloric acid, the results showed that peptization of the precipitate favored formation of the rutile phase and highly crystalline anatase. Particles of the 100% rutile phase with high specific surface areas were obtained at relatively low temperatures. The specimens were characterized by transmission electron microscopy (TEM), X-ray diffractometry, Brunauer-Emmitt-Teller (BET) surface area analysis, and differential thermal analysis. To evaluate the effects of different phases on the degradation efficiency, anatase/rutile mixtures exhibited the best catalytic efficiency for the degradation of sodium benzenesulfate (BS), while pure rutile was the poorest catalyst.

Dielectric relaxation and mechanical properties of natural and chloroprene rubber with some nitroaniline additives

A systematic dielectric study over a frequency range from 400 to 10 MHz was carried out on natural rubber and chloroprene rubber with a small amount of nitroaniline additives. Three absorption regions were obtained as a result of the analysis of the curves relating dielectric loss ϵ″ with frequency. The first absorption region in the lower-frequency range could be attributed to the Maxwell–Wagner effect. The second adsorption region which could be attributed to the ingredients added to rubber was found to be nearly the same for doped and undoped natural region which could be attributed to the ingredients added to rubber was found to be nearly the same for doped and undoped natural rubber samples, while it decreases by the addition of aniline derivatives to chloroprene rubber samples. The third region which is associated with Debye losses is found to be also nearly the same for natural rubber samples, while it decreases by the addition of aniline derivatives to chloroprene rubber; this decrease is interpreted according to the peptizing effect of aniline derivatives. For the expired chloroprene rubber gum, aniline derivatives were added and the mechanical and electrical behavior was improved to approach the unexpired one. © 1996 John Wiley & Sons, Inc.

Effect of Peptization on Densification and Phase‐Transformation Behavior of Sol–Gel‐Derived Nanostructured Titania

Porosity reduction, packing, pore‐size distribution, and anatase to rutile phase transformation behavior of nanostructured titania ceramics prepared from both peptized and unpeptized sols were studied and compared using XRD, DSC, and nitrogen‐gas physisorption techniques. Precursor gels prepared from the peptized sol had a green density of about 70% after drying at 40°C, whereas the samples prepared from the unpeptized sol had a green density of only 50%. Samples prepared from the peptized sol showed higher sintering and phase transformation rates compared to the unpeptized sols.

Effect of Gel and Nonrubber Constituents on the Extrusion Properties of Guayule Rubber

Abstract An experimental study on the effect of gel and nonrubber constituents on the extrusion behavior of guayule rubber (GR) has been carried out. At 140°C, gel increases the viscosity at low shear rates. When GR is properly stabilized, no peptizing effect is imparted by the resin. However, the resin acts as a moderate plasticizer as compared to paraffinic oil. At 120°C, the effect of gel is noticeable at high extrusion rates, increasing the viscosity, suggesting an increase in the tendency for the occurrence of flow-induced crystallization.

コンニャクマンナンのゲル化に関する速度論 ＩＩ コンニャクマンナンのゲル化における誘導反応速度の凝固剤への依存性

The variation in velocity of induced reaction of gelation of konjac mannan with the sort and concentration of gelatinizer was measured by use of an amylograph. The velocity varied with the concentration of OH- but not with that of gelatinizer itself. The variation profile was almost independent of the sort of gelatinizer. The gelatinizer seems to play the role of reservoir or provider of OH-. The relation between the velocity and the concentration of OH- is derived as follows;V=K[OH]n, where V (min-1) is the velocity, [OH] the concentration of OH-(M), K and n the constants. As the value of n is less than 1, the formation of junction of konjac mannan seems to be hindered with increasing concentration of OH-. From the result, it is concluded that OH- acts as not only the initiator of gelation being due to the deacetylation, but also the inhibitor probably due to the peptizing effect of the ion.

The stabilizing effect of Na 2S on the collector coating of chrysocolla

The heterogeneous reaction between natural and sulphidized chrysocolla and potassium amyl xanthate in solution is investigated. It is found that, together with the consumption of large amounts of xanthate, particles composed of the reaction products are spontaneously released from the surface of chrysocolla giving rise to a colloidal dispersion. In principle the mechamism is related to the peptizing effect of the excess xanthate ions that are found when Cu 2+ and X − ions are made to react in a homogeneous phase. In sulphidized chrysocolla this phenomenon is markedly reduced, showing that Na 2S has a stabilizing effect on the collector coating. Flotation experiments performed with aqueous amyl dixanthogen emulsions show that stable adhesion occurs only on properly sulphidized chrysocolla. It is believed that the mechanism controlling adhesion in this case is similar to that which determines the stability of the collector layer.

Studies on the peptization of ferric hydroxide. I. Peptizing effect of hydrochloric acid (author's transl)

Peptization of ferric hydroxide by hydrochloric acid was examined. Precipitate of ferric hydroxide was added to an aqueous solution of hydrochloric acid and agitated for 30 min at 80° or boiled for 30 min. Efficiency of peptization was evaluated from the concentration of ferric hydroxide in the sol, which was determined by chelatometry after the colloidal particles had changed to ferric ion. It has been found that there is a maximum point of peptization at appropriate amount of ferric hydroxide precipitate added to hydrochloric acid. The degree of peptization increased with the amount of hydrogen ion adsorbed on the particle. The adsorption isotherm of hydrogen ion on the ferric hydroxide particle is well reproduced with Freundlich's equation. The minimum amount of hydrogen ion required to be adsorbed in order to peptize the particle (xmin) depends on ionic strength of the colloidal system (J), and the relation was experimentally determined as follows : xmin=0.95 √(J)+0.03 It has been concluded that hydrogen ion is responsible for peptization of ferric hydroxide as well as for stabilization of colloidal ferric hydroxide particles at about pH 2.5-5, while ferric ion cooperates with hydrogen ion to peptize and stabilize the sols at pH below 2.5.

Effect of peptization of aluminum hydroxide on quality of ?-Al2O3

Effect of peptization of aluminum hydroxide on quality of ?-Al2O3

Separation of colloidally dispersed material-emulsifiers from petroleum by ultrace ntrifugaton

1. The basic portion of materials dispersed in petroleum is separated in the first few hours of ultracentrifugation. 2. After separation of colloidally dispersed compounds the petroleum virtually does not stabilize the emulsion. 3. The deemsulsifier has a peptizing effect on colloidally dispersed materials. In this case the peptizing effect of deemulsifying effectiveness. 4. The presence of metal-porphyrin complexes of vanadium in colloidally dispersed compounds contained in petroleum was shown.

Zinc as a Cathodic Inhibitor

It was shown that zinc metal in close contact with a noble metal such as silver furnishes zinc ions to an aqueous solution. A binuclear zinc hydroxide complex cation seems to be formed which can act as a cathodic inhibitor. This ion also acts as a buffer removing CO2 and it reacts with the oxygen in the water to give additional hydroxide ions.Considerable attention is given to the investigation of the nature of zinc complexes. Other topics discussed include nature of the cathodic protective coating forming on zinc, effect of the addition on impurities to zinc, and peptizing effect of the zinc hydroxide complex. 5.8.4