THERMODYNAMICS OF ALKANOLAMINE + WATER SYSTEM

Design of gas treating processes requires knowledge of the vapor-liquid equilibrium behavior of the (acid gas + aqueous alkanolamine) system. The present study is focused on thermodynamics and associated nonideal behavior of binary MEA + H₂O, DEA + H₂O, and MDEA + H₂O systems, which is required to predict the vapor-liquid equilibrium of acid gases such as CO₂ and H₂S over aqueous alkanolamine solutions. Determination of binary interaction parameters and analytical prediction of infinite dilution activity coefficient, heats of solution at infinite dilution, the excess Gibbs free energy, and excess enthalpy for nonideal alkanolamine-water systems are the objectives of this study.     

SYNTHESIS AND OXIDATION OF N-ALKYLACRIDANS

本文用金属钠和正戊醇还原Ｎ－烃基啶酮法合成了十一个Ｎ－烃基啶满，并用紫外光谱法研究了它们和ＤＤＱ、ＴＣＮＥ与ＣＡ的氧化反应．它们只能和ＤＤＱ形成电荷转移络合物，不能和ＴＣＮＥ或ＣＡ形成电荷转移络合物，其原因是ＤＤＱ有较强的络合能力和较弱的氧化能力，ＴＣＮＥ和ＣＡ则相反，有较弱的络合能力和较强的氧化能力．并用两种方法求得了Ｎ－烃基啶满的电离势（Ｉｐ）值，结果很接近．     

PHASE EQUILIBRIA OF CLATHRATE HYDRATES IN HYDROGEN SULFIDE + DIETHYLENE GLYCOL OR TRIETHYLENE GLYCOL + WATER SYSTEM

In this communication, experimental hydrate dissociation pressures for hydrogen sulfide + diethylene glycol (DEG) + water and hydrogen sulfide + triethylene glycol (TEG) + water systems are reported in the 276.8–288.3 K and 271.3–289.5 K temperature ranges for 0.05 and 0.15 mass fractions of DEG in aqueous solution and 279.0–289.9 K and 276.9–290.6 K for 0.05 and 0.15 mass fractions of TEG in aqueous solution, respectively. The experimental data were generated using an isochoric pressure-search method. The experimental hydrate dissociation data were compared with some selected literature data in the presence of pure water. In the concentration ranges studied in this work, it is shown that both DEG and TEG aqueous solutions have inhibition effects on hydrogen sulfide clathrate hydrates. Approximately the same inhibition effects are found for the DEG and TEG aqueous solutions studied in the presence work.     

VAPOR-LIQUID AND LIQUID-LIQUID EQUILIBRIA OF THE SYSTEM OF 4-METHYL-2-PENTANOL AND WATER

IntrodUCtion 今Methyl一2一Pentanol 15 a very imPortant solvent for eoPPer,iron and eoal floating.The mutual solubility of it with water 15 exeeedingly small at ordinary Pressure.50 far in the1 iterature available we ean find only the LLE(Liquid一Liquid Eq…     

SOLUBILITY OF ACETAMINOPHEN AND IBUPROFEN IN BINARY AND TERNARY MIXTURES OF POLYETHYLENE GLYCOLS 200 AND 400, PROPYLENE GLYCOL,AND WATER AT 25°C

The solubilities of acetaminophen and ibuprofen in the mixtures of propylene glycol-water, polyethylene glycols 200- and 400-propylene glycol, and polyethylene glycols 200- and 400-propylene glycol-water (122 data points) at 25°C were determined and mathematically represented by the Jouyban-Acree model. The solubilities were measured using the shake flask method, and the model was used to fit the solubility data of each drug in the solvent mixtures. The density of the solute-free solvent mixtures was measured and the density of the drug-saturated solutions was predicted. The obtained overall mean relative deviations (OMRDs) for fitting the solubility data of acetaminophen and ibuprofen in binary mixtures are 1.5% and 11.7%, respectively. The OMRDs for fitting the solubilities in ternary solvent mixtures for acetaminophen and ibuprofen are 16.3% and 42.0%, respectively, and the OMRD values for predicting all solubilities of acetaminophen and ibuprofen by these trained versions of the Jouyban-Acree model were 5.7% and 20.4%, respectively. The prediction OMRD for the density of saturated solutions was 2.5%.     

EFFECT OF MAGNETIZATION OF WATER ON INDUCTION TIME AND GROWTH PERIOD OF NATURAL GAS HYDRATE

The effect of diluted solution's magnetization on induction time and growth period of natural gas hydrate (NGH) has been investigated in quiescent reaction system at pressure of 4.5 MPa and temperature of 274 K with SDS as surfactant, by using volume fixed and pressure falling method. Experimental results show that magnetization will have effect on the induction time of NGH. After magnetization with magnetic field intensity of 0.33 T, the induction time of NGH has been reduced to 47 min (average) from 99 min (average) in which there is no magnetization. On the other hand, the induction time has been prolonged after magnetization of the diluted solution with magnetic field intensity of 0.05 T, 0.11 T, 0.22 T, 0.44 T. Especially with magnetic field intensity of 0.11 T, the induction time had even been prolonged to 431 min (average). The effect of magnetization on the growth period of NGH has not been found at the experimental condition.     

KINETICS OF HYDROGEN PRODUCTION BY PARTIAL OXIDATION AND STEAM REFORMING OF METHANOL

1　INTRODUCTIONWithdecreasingoilreservesanddeterioratingenvironment,the problemofenergyandenvironmenthasbecomethemainobstacletothesustainabledevelopmentofeconomyandthe progressofmankind Inmanydevelopedcountriesfuelcellsareextensivelyresearched Inallkindso…     

APPLICATION AND FUNDAMENTAL RESEARCH OF ROTATING STREAM TRAY

ＡＰＰＬＩＣＡＴＩＯＮＡＮＤＦＵＮＤＡＭＥＮＴＡＬＲＥＳＥＡＲＣＨＯＦＲＯＴＡＴＩＮＧＳＴＲＥＡＭＴＲＡＹＴａｎＴｉａｎｅｎ；ＳｈｉＨｕｉｘｉａｎｇ；ＣｈｅｎＪｉａｎｍｅｎｇ；ＳｈｉＸｉａｏｒｏｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｃａｌＥｎｇｉｎ...     

SYNTHESIS OF UNSATURATED POLYESTER RESIN—EFFECT OF CHOICE OF REACTANTS AND THEIR RELATIVE PROPORTIONS

Unsaturated polyesters are synthesized in the laboratory by the condensation of saturated and unsaturated anhydrides with glycols. The condensate obtained is mixed with styrene monomer to get an unsaturated polyester resin formulation. The properties of the polyester resin synthesized are affected by the synthesis parameters. In this study, the parameters investigated are the effect of choice of reactants and their relative proportions. Properties such as tensile strength, tensile modulus, elongation-at-break, toughness, impact strength, surface hardness, abrasion resistance, and water absorption were tested after curing the resin. Various combinations of (a) maleic anhydride and phthalic anhydride, (b) propylene glycol and ethylene glycol, and (c) propylene glycol and diethylene glycol were used to investigate the effect on the properties of the synthesized resin. The combinations of the anhydrides and glycols that give optimum properties are identified. The results show that most of the properties are maximum at 60% maleic anhydride composition in a mixture of maleic anhydride and phthalic anhydride. Similarly, a better balance of properties is obtained when propylene glycol is mixed with 30% ethylene glycol or 20% diethylene glycol.     

CORRELATION OF DIFFUSION COEFFICIENTS FOR LIQUIDS AND DENSE FLUIDS WITH TEMPERATURE AND PRESSURE

On the basis of the free volume theory and activation energy concept,a fundamental equation whichtakes into account the effects of temperature and pressure has been developed.By introducing differentexpressions for the free volume and activation energy,several equations for fluid diffusion coefficients were derivedaccordingly.With the van der Waals free volume and intermal energy formula,a three-parameter model for fluiddiffusion coeffficients at moderate pressure was obtained.The grand average absolute deviation percent of 345data points (44 systems)for self-and infinite dilute inter-diffusivities is 2.32,against the results of the model ofCohen and Turnbull,4.13.In particular,by means of the modified Carnahan-Starling free volume equation,afour-parameter model with average abosolute deviation percent 2.64(30 systems,644 data points)for theestimation of dense fluid inter-and self-diffusivities at high pressures and in supercritical conditions was derived.The derived model is superior to the method of L     

SYNTHESIS AND SWELLING PROPERTIES OF NOVEL SUPERABSORBENT POLYMER

1　INTRODUCTIONSuperabsorbentpolymers (SAPs)arenewfunctionalmaterials,whichcanabsorbandretainanunusuallylargeamountofwaterandbodyfluid .Theyhaveavarietyofvaluableapplications[1,2 ] becauseoftheiruniquecharacteristics ,andtheycanbedividedintotwoclasses:non…     

NUMERICAL MODELING OF SUSPENSION TWO-PHASE FLOWS AND THEIR COMBUSTION CURRENT STATUS AND DEVELOPMENT

The background, history and development of numerical modeling of suspension two-phase flows and their combustion are reviewed. Different models, including single-fluid model, particle trajectory model, multifluid model and continuum-trajectory model, their numerical procedure and application are discussed. The advantage and drawback of these models are analyzed. Finally, the prospect of development is described and the contributions made by the present author are also incorporated.     

MONTE CARLO MODEL OF BACKMIXING AND REACTION OF PARTICLES IN CONTINUOUS FLOW SYSTEM

A stochastic approach,namely,Monte Carlo method with“tree structure pattern”has been adopted tosimulate the random backrnixing,residence time,reaction and dynamics of solid particles with size distribu-tion and with complex reaction in a complex flow system.Turbulence of particles in reactor system is simu-lated by stochastic tree pattern which is shown by pseudo-random number series picked from a uniformlydistributed set of numbers between zero and one.A Monte Carlo procedure is employed to model the par-ticles’ stochastic residence time,random flow and reaction with fluid.A large number of discrete bundlesof particles have been simulated and followed.Statistic results of all particles in the last information representthe solution to the problem under steady state of flow.The approach has a simple physical concept and simulation procedure.All calculation has been carriedout easily with a computer.For simple reaction system,results are in good agreement with those obtainedfrom the known approach and experiments.The method could provide a new kind of technique for simu-lating the behavior of particles in a continuous flow reactor.     

PREPARATION AND CHARACTERIZATION OF THE INTERCALATION COMPOUNDS OF α-HAFNIUM PHOSPHATE WITH METHYLPIPERIDINES

ABSTRACT

The mechanism of intercalation reactions between 4-methylpiperidine and n-methylpiperidine with α-HfP in aqueous media has been studied. The intercalated solids obtained are characterized by chemical and thermal analysis, X-ray diffractions and IR spectroscopy. Titration and intercalation isotherms, hydrolysis curves, corrected isotherms, and phase distributions are obtained. Two new phases with the composition α-Hf(HPO₄)·amine·H₂O are isolated and characterized. The influence of basicity and steric factors on the intercalation behaviour is discussed. The arrangement of the two isomeric forms of methylpiperidine in the interlayer space is postulated.     

DETERMINATION OF PHASE EQUILIBRIA AND CRITICAL LOCUS OF CO_2-HCFC22 SYSTEM

1 INTRODUCTIONHydrochlorofluorocarbons(HCFCs)and hydrofluorocarbons(HFCs)are alternatives tochlorofluorocarbons(CFCs),such as CFC12(freon 12),which has been widely used asan aerosol agent and working fluid of domestic1:ICthdflC(CHCIFZ,HCFC22,R22)is one of the potential alternatives.It Is also one of the po-tentlal entralner for supercrltlcal fluid CO,extraction.     

THE APPLICATIONS OF A GENERALIZED EQUATION OF STATE TO THE CORRELATION AND PREDICTION OF PHASE EQUILIBRIA∗

Two methods of generalizing an equation of state are demonstrated and their limitations are outlined. One method involves the correlation of the equation of state constants and the second method involves a recently proposed Generalized Corresponding States Principle based on the properties of two (nonspherical) reference fluids. The PVT properties of pure fluids are represented by a new cubic equation of slate with four parameters which are obtained from vapor pressure and saturated liquid density data. It is demonstrated how a limited amount of data on key components may be used to obtain phase equilibria in mixtures.     

VIABILITY AND ACTIVITY OF MICROORGANISMS IN SUPERCRITICAL CO_2

INTRODUCTIONIn situremovalofinhibitoryproductsbysupercriticalfluidextraction (SCFE )hasdrawnmuchattentionrecently[1,2 ] SupercriticalCO2 (SCCO2 ) possessesmanyadvantagesoverorganicsolventsduetoitsspecialcharacteristicsandenvironmentalbenefits [1,3— 5] I…     

SOLUBILITY OF LAMOTRIGINE IN BINARY AND TERNARY MIXTURES OF PEGS 200, 400, AND 600 WITH ETHANOL,PG, AND WATER AT 298.2 K

Experimental solubilities of 6-(2,3-dichlorophenyl)-1,2,4-triazine-3,5-diamine (lamotrigine) in binary and ternary solvents of polyethylene glycols (PEGs) 200, 400, and 600 with ethanol and water, and PEGs 200, 400, and 600 with propylene glycol (PG) and water at T = 298.2 K are reported. The Jouyban-Acree model was used to fit solubility data of lamotrigine in the binary and ternary solvent mixtures (145 data points) in which the overall mean relative deviation (OMRD %) was 11.5%. The density of the solute-free solvent mixtures was measured and employed to calculate the constants of the Jouyban-Acree model and then the density of the saturated solutions is predicted.