Tribological Behaviors of S,B-Containing Morpholine Derivatives as Additives in Rapeseed Oil

Two novel ashless and non-phosphorus S, B-containing morpholine derivatives, MBOC and MBOD, were prepared and their tribological behaviors in rapeseed oil （RSO） were evaluated using a four-ball tester. Thermal degradation tests were conducted to identify their thermal stabilities using a thermo-gravimetric analyzer. The worn surfaces of the steel balls were investigated by scanning electron microscopy （SEM）. The results indicated that the additives possessed high thermal stabilities and good load-carrying capacities. Moreover, they both had good anti-wear and friction reducing property at a relatively high concentration （1.5 m%） and under all test loads. The results of XPS analyses illustrated that the prepared compounds as additives in RSO could form a protective film containing inorganic sulfide, sulfate, oxidized compounds and organic nitrogen-containing compounds on the metal surface during the sliding process.     

Effect of 3-aminotriazole on the corrosion of copper in polluted and unpolluted media

The inhibition of copper corrosion in unpolluted or polluted 3.5% NaCl solution in the absence and presence of 3-amino-1, 2, 4-triazole （ATA） as a corrosion inhibitor was studied by using different electrochemical techniques. Aminotriazole （ATA） is well known as corrosion inhibitor for corrosion of copper and aluminum in unpolluted salt water. The influence of 3-aminotriazole （ATA） on the corrosion behavior of copper in unpolluted and polluted environment has been studied using potentiodynamie and potentiostatic polarization methods. Surface morphological examinations such as SEM, EDS and XPS have also been carried out to understand the mechanism of inhibition of corrosion. Electrochemical measurements and morphological results are clearly show that the inhibitor is strongly adsorbed on the copper surface and form a protective film on the copper surface.     

Study on Laboratory Method for Refining of SR Diesel Fuel

The method for refining the straight-run diesel fuel was studied in laboratory scale in order to make the acid number of diesel fraction comply with the standard while removing the naphthenic acids contained in diesel without causing environmental pollution. After comparing the effect of refining using three solvents, the isopropyl alcohol-HOA was specified as the best solvent. Meanwhile, the relationship between the acid number of diesel fraction and the amount of solvent used and the relationship between the concentration of solvent and temperature and the stability of diesel in terms of its acid number were also investigated. Experimental results had shown that when the mass fraction of the HOA-IPA solvent was 20% at a dosage of 17 mL of the solvent and a temperature of 30℃, the acid number of the refined diesel fraction was 0.015 mg KOH/g with a good stability of acidity in the diesel fraction,     

A pH Model for Calculating the pH Value of Mixed–Acid–Base Equilibria of Overhead Condensing Systems in Crude Distillation

A pH predictive model based on acid–base equilibria and ion equilibria was proposed to calculate the pH value of the overhead condensing system of crude distillation unit. The pH model could be used to predict the appropriate amounts of neutralizers by measuring the Cl-ion concentration of the overhead knockout drum. The pH values of various neutralized streams were estimated by this model. The results showed that the predicted pH values were in good agreement with the experimental ones. The trend of the corrosion inhibition efficiency decreases in the following order: ethylenediamine N,Ndimethylethanolamine triethylamine 3-methoxypropylamine morpholine. The difficulty in the accurate control of corrosion was solved, and a good instruction was provided for mitigating corrosion in refinery.     

Effect of Lithium Nitrate on the Structure and Property of α-Al_2O_3 Platelets Prepared via Solid-state Reaction

The α-Al_2O_3 platelets were prepared via solid-state reactions and the effect of the amount of lithium nitrate additive on the property of the platelets was investigated. The ICP results indicated that the high temperature calcination process resulted in a large loss of lithium species because of volatilization, but there was still a small amount of residual lithium species in the α-Al_2O_3 platelets. The SEM micrographs showed that lithium nitrate led to decrease in the thickness of α-Al_2O_3 platelets and irregular morphology of aggregates. Pore structures results exhibited that addition of lithium nitrate led to decrease in the pore size and increase in the specific surface area of aggregates of α-Al_2O_3 platelets. The XRD and IR patterns suggested that the residual lithium and aluminum oxide formed LiAl_5O_8. The existence of LiAl_5O_8 was the basic reason for the changed performance of α-Al_2O_3 platelets.     

Protection and Functionalizing of Stainless Steel Surface by Graphene Oxide-Polypyrrole Composite Coating

The corrosion inhibition of metallic substrates is a prime issue for many potential applications where corrosion plays a crucial role. The development of carbon based on functionalized coatings could increase the lifetime of metallic substrates by inhibiting the corrosion process. Present work is an effort to develop a corrosion inhibiting composite coating of graphene oxide and polypyrrole for AISI （American Iron and Steel Institute） type 304 stainless steel substrates. The electrochemical galvanostatic deposition process was applied for coating development. The coating morphology and ability to cover the substrate surface was analyzed with a high-resolution scanning electron microscope. The coating＇s structural and electronic properties were analyzed with Raman spectroscopy. The investigation of corrosion inhibition involved open circuit potential, Tafel, and voltammetry analysis. The standard salt test ASTM （American Society for Testing and Materials） G48A for stainless steel substrate has also been studied. Significant enhancement of corrosion potential as well as pitting potential for the composite coated substrates has been noted. Furthermore, corrosion and breakdown potential increased upon changing the material from graphene oxide to its composite coating. During the salt test analysis, the durability of the composite coating was noted up to 72 h, which is the standard time scale. Based on experimental analysis, this composite material can be used as an effective carbon based on functionalized corrosion inhibitor for stainless steel substrates to increase their lifetime.     

Molecular Simulation of Naphthenic Acid Removal on Acidic Catalyst （I） Mechanism of Catalytic Decarboxylation

In this paper, the charge distribution, the chemical bond order and the reactive performance of carboxylic acid model compounds on acidic catalyst were investigated by using molecular simulation technology. The simulation results showed that the bond order of C-O was higher than that of C-C, and C-C bond connected to the carbon atom in the carboxyl radical had the lowest bond order. The charge distributions of model naphthenic acids were similar in characteristics that the negative charges were concentrated on carboxyls. According to the simulation results, the mechanisms of catalytic decarboxylation over acidic solid catalyst were proposed, and a new route was put forward regarding removal of the naphthenic acid from crude oil through catalytic decarboxylation.     

Exploitation of methane in the hydrate by use of carbon dioxide in the presence of sodium chloride

The replacement process of CH4 from CH4 hydrate formed in NaCl solution by using pressurized CO2 was investigated with a self-designed device at temperatures of 271.05,273.15 and 275.05 K and a constant pressure of 3.30 MPa.The mass fraction of the NaCl solution was either 0.5 wt% or 1.0 wt%.The effects of temperature and concentration of NaCl solution on the replacement process were investigated.Experimental results showed that high temperature was favorable to the replacement reaction but high NaCl concentration had a negative effect on the replacement process.Based on the experimental data,kinetic models of CH4 hydrate decomposition and CO2 hydrate formation in NaCl solution were established.The calculated activation energies suggested that both CH4 hydrate decomposition and CO2 hydrate formation are dominated by diffusion in the hydrate phase.     

Time-sensitivity of the Kaiser effect of acoustic emission in limestone and its application to measurements of in-situ stress

Measuring in-situ stress by using the Kaiser effect in rocks has such advantages as timeefficiency, low cost and little limitation, but the precision of the method is dependent on rock properties and delay time of the measurement. In this paper, experiments on the Kaiser effect in limestones were performed, and it was found that the limestones had good ability to retain a memory of their recent stress history and high time-sensitivity. The longer the experiment was delayed from the extraction of the stone, the larger the Felicity ratio was. As the Felicity ratio approached l, significant Kaiser effect was observed. In-situ stress should be determined by the limestone measurements when the delay time was 40-120 days. Finally, the in-situ stress in a limestone formation could be successfully measured in practice.     

金属氧化物对ZSM-5分子筛催化裂化性能的影响

Effects of metal oxide in ZSM-5 zeolite on its catalytic performance in fluid catalytic cracking reaction were studied via characterization by XRD and FT-IR spectroscopy using pyridine and collidine as molecular probes,and the modified ZSM-5 zeolite was evaluated in a micro reactor using standard light diesel fraction as the feedstock.Test results indicate that the metal species introduced into the ZSM-5 zeolite had led to the formation of Lewis acid centers.When the modified ZSM-5 zeolite with the metal species on its surface was used as the catalyst in FCC reaction,both the propylene yield and the propylene concentration in the liquefied petroleum gas increased,but in the meantime,more hydrogen and coke were formed at high conversion rate under the joint action of nonselective cracking of Lewis acid centers and dehydrogenation at metal centers on its outside surface.     

离子交换树脂稳定性研究：Ⅱ. 异丁烯二聚反应中的解磺化

The performance of ion-exchange resin catalysts during isobutene (IB) dimerization was investigated under different IB contents,temperatures and liquid-volume hourly space velocity (LHSV) using a plug flow reactor in the absence of any selectivity enhancing component.High IB content and temperature resulted in a high conversion and C12 selectivity bu low C8 selectivity.The influence of LHSV was related with the IB content:LHSV had great effect at high IB content,while the performance of ion-exchange resin changed little with LHSV if IB content was low.The effect of water on the stability of resins was also studied.Desulfonation was observed during the C4 dimerization reaction when water was added to the feed.Chlorinated resin was more stable than conventional polystyrene-based resins during the test.     

Experimental and Molecular Simulations for Evaluating the Effect of Lubricity Improvers on the Property of Jet Fuel

Since the 1990 s, the kerosene fuel(code: JP-8) had been applied in the ground equipment provided with direct injection compression ignition engines in the U.S. Army, resulting in increased occurrence of injection pump failures. Anti-wear additives must be used in the single fuel due to its poor lubricity. In the present work, lubricity improvers were selected on the basis of molecular simulation theoretically and these agents were evaluated to improve the lubricity of jet fuel using the high frequency reciprocating rig(HFRR) apparatus and the ball-on-cylinder lubricity evaluator(BOCLE). It was revealed that dimer acid with higher value of adsorption energy on the Fe(110) plane surface had more efficient lubricity promoting properties than that of naphthenic acid. The experimental results suggested that the dimer acid had a better tribological behavior compared with that of naphthenic acid used as lubricity improver of jet fuel. And addition of anti-wear additives at a dosage of 15 μg/g was able to promote the lubricity of jet fuel to a required level on BOCLE, while a higher concentration over 80 μg/g was needed to improve the lubricity to a demanded value of diesel on HFRR.     

The effects of sulfide stress cracking on the mechanical properties and intergranular cracking of P110 casing steel in sour environments

Variation and degradation of P-110 casing steel mechanical properties, due to sulfide stress cracking (SSC) in sour environments, was investigated using tensile and impact tests. These tests were carried out on specimens, which were pretreated under the following conditions for 168 hours temperature, 60 °C; pressure, 10 MPa; H2S partial pressure, 1 MPa and CO2 partial pressure, 1 MPa; preload stress, 80% of the yield strength (σs); medium, simulated formation water. The reduction in tensile and impact strengths for P-110 casing specimens in corrosive environments were 28% and 54%, respectively. The surface morphology analysis indicated that surface damage and uniform plastic deformation occurred as a result of strain aging. Impact toughness of the casing decreased significantly and intergranular cracking occurred when specimens were maintained at a high stress level of 85% σs .     

Study on the Effect of Catalyst Properties on Residue Hydroconversion

The effect of catalyst properties on residue oil hydroconversion was studied at moderate operating conditions(at a temperature of 400 ℃, an initial hydrogen pressure of 10 MPa, and a reaction time of 4 h) in a batch mode slurry phase with different catalyst samples. The results showed that the catalyst acidity had a good effect on residue conversion and MCR(micro carbon residue) conversion but brought about higher coke yield. Residue conversion was thermally induced but the catalyst acidity changed its conversion route. A catalyst with higher metal loading, higher hydrogenation activity and appropriate pore size had higher sulfur and metal removal rate, higher MCR conversion and also a lower coke formation. The activity of spent commercial catalyst AS1 and DS1 was slightly lower than the corresponding fresh ones but was still high enough for residue oil hydroconversion. It assumes that the role of the catalyst is to activate hydrogen species toward reaction with an aromatic carbon radical to yield a cyclohexadienyl type intermediate which will turn into liquid and also to absorb the mesophase which can easily aggregate to form coke.     

Synthesis of Modified β-Zeolite Under Microwave Irradiation and Its Use on Etherification

β -zeolite was synthesized by using tetraethyl ammonium hydroxide as the template reagent and microwave radiation as the heat source. The effect of the sol composition and the radiation temperature on zeolite crystallinity was investigated. The zeolite was tested and compared with the commercial product, which was produced by conventional hydrothermal synthesis method. ,The physico-chemical properties of the synthesized samples, the specific surface area of the samples synthesized under microwave irradiation and pore volume measured by X-ray diffraction apparatus, were better than the conventional samples. The etherification experiment on FCC light naphtha in the presence of transition metals modified H β -zeolite, which was synthesized firstly under microwave irradiation, was studied in a fixed-bed reactor. The effect of catalyst preparation conditions on its activity, stability and the effect of reaction temperature, methanol/tertiary-carbon olefin molar ratio and liquid hourly space velocity on the etherification reaction were discussed. The experimental results showed that the different metals modified H β -zeolite had different etherification performances. And the conversion of tertiary carbon-olefins of the molybdenum modified H β zeolite, which was loaded at a concentration of 3 percents, was higher than that on 6.0 percent of H β zeolite. The modified H β zeolite catalysts possessed favorable prospects for its higher stability.     

Formation mechanism of micro-flows in aqueous poly（ethylene oxide） droplets on a substrate at different temperatures

The drying of aqueous poly(ethylene oxide)(PEO) droplet on a substrate at different temperatures was studied.It was found that the contact line receded when the substrate was at a temperature above 60 oC.Different nucleation behavior and surface profiles of PEO films were found in different droplets drying processes.The rheological properties of aqueous PEO solutions were studied to understand the mechanism of contact line recession and micro-flow in drying aqueous PEO droplets.It was found that at low temperature,the contact line was static because of great viscous stress;while at high temperature,it receded because of great Marangoni force and the decrease of viscous stress.It was indicated that Marangoni convection was inhibited by the outward capillary flow and viscous stress at low temperature,whereas it became dominant at high temperature.Two types of mechanism for surface profiles and nucleation of PEO film from drying droplets are proposed,providing a theoretical guide for polymer solution application in oil and gas foam flooding technology.     

Catalytic performance of Pt/HY-β in n-octane hydroisomerization

A bifunctional catalyst Pt/HY-β was prepared from a bimicroporous composite zeolite Y-β. Characterization results showed that the specific surface area, pore volume, and acid amount of the catalyst Pt/HY-β all decreased compared to the original zeolite. The catalytic performance of this catalyst in n-octane hydroisomerization was investigated in a fixed bed stainless steel tubular reactor. The results showed that at a hydrogen/n-octane volume ratio of 1000, pressure of 0.6 MPa, temperature of 230 ℃ and LHSV of 3 h^-1, the conversion of n-octane, yield of liquid, hydrocracking rate and yield of iso-octane were 52.32%, 88.66%, 12.60%, 39.51%, respectively.     

Laccase Immobilized on Mesoporous Silica Materials and Its Corrosion Inhibition Performance in Circulating Cooling Water System

Mesoporous SiO_2 microspheres were synthesized using the sol-gel method and were characterized by TEM, FT-IR and BET techniques. The diameter of the microspheres is about 100—150 nm, and the average mesopore diameter is 2.55 nm, while the specific surface area is 1 088.9 m2/g. Mesoporous SiO_2 microspheres adsorb glutaraldehyde and immobilize laccase by means of the aldehyde group in glutaral which can react with the amidogen of laccase. The immobilization conditions were optimized at a glutaraldehyde concentration of 0.75%, a crosslinking time of 8 h, a laccase concentration of 0.04 L/L and an immobilization time of 10 h. When diesel leakage concentration was 80 mg/L, the highest corrosion inhibition efficiency of immobilized laccase reached 49.23%, which was slightly lower than the corrosion inhibition efficiency of free laccase(59%). The diesel degradation ratio could reach up to 45%. It has been proved that the immobilized laccase could degrade diesel to inhibit corrosion.     

Oxidative Desulfurization of Diesel Fuel with Hydrogen Peroxide Using Na_2WO_4 as Catalyst

Oxidative desulfurization was performed on Na2WO4 catalyst in the presence of hydrogen peroxide and acetic acid under mild reaction conditions (atmospheric pressure and temperature range of 293—343 K). Different organic compounds including benzothiophene (BT), dibenzothiophene (DBT), 4, 6-dimethyl dibenzothiophene (4, 6-DMDBT) were used to investigate the reactivity of this catalyst, and the effect of various parameters, such as temperature, solvents and the amount of oxidant reagent used in oxidative desul...     

新型给电子体聚丙烯催化剂的研究

A P-substituted sulfonyl-containing compound was synthesized in the lab. The structure of the compound was demonstrated by 1H and 31P NMR. The propylene polymerization catalysts were prepared by incorporating an internal donor, and the content of Ti, H and C in the catalysts was also checked by elemental analysis. The effect of dosage of the donor, the Al/Ti ratio and the polymerization temperature on the catalyst activity were studied, the results suggested that the dosage of donor, the Al/Ti ratio and the polymerization temperature could affect not only the activity of catalyst but also the isotacticity index of the polymer. A catalyst with high activity was selected, and the polypropylene formed in the presence of this catalyst had high isotacticity index.