Solubility measurement,correlation and thermodynamic properties of 2,3,4-trichloro-1,5-dinitrobenzene in fifteen mono-solvents at temperatures from 278.15 to 323.15 K

The solubility of 2,3,4-trichloro-1,5-dinitrobenzene(TCDNB) was measured by a laser dynamic method over the temperature range from 278.15 K to 323.15 K under 0.1 MPa in fifteen mono-solvents(methanol,ethanol,isopropanol,n-butanol,toluene,dichloromethane,chloroform,tetrachloromethane,1,2-dichloroethane,acetone,ethyl acetate,acetonitrile,N-methylpyrrolidone(NMP),N,Ndimethylformamide dimethyl sulfoxide(DMF),dimethyl sulfoxide(DMSO).The solubility of TCDNB could be increased with increasing temperature in fifteen mono-solvents.TCDNB solubility is in the following order at 298.15 K:NMP>DMF>DMSO>toluene>acetone>ethyl acetate>dichloromethane>1,2-dich loroethane>chloroform>acetonitrile>tetrachloromethane>methanol>ethanol>n-butanol>isopropanol.The KAT-LSER model was used to investigate the solvent effect,which revealed that the hydrogen bond acidity of solvents has a greater effect on TCDNB solubility.The van't Hoff model,the modified Apelblat model,theλh model,and the non-random two liquid(NRTL)model were used to correlate the solubility of TCDNB.The calculated solubility data agreed well with the experimental data,and the modified Apelblat model fit best.Furthermore,the van't Hoff and Gibbs equations were also used to calculate the dissolution thermodynamic properties of TCDNB in various solvents.TCDNB dissolution could be an enthalpy-driven,non-spontaneous,and endothermic process in fifteen mono-solvents.The determination and fitting solubility of TCDNB,as well as the calculation of its thermodynamic properties,would be critical in the purification and crystallization of its preparation process research.

A New Example of Retrograde Solubility Model for Carbonate Rocks

Objective The dissolution and precipitation of carbonate during burial diagenetic process controls the reservoir property in deep buried strata. The geological process related with it has become a research focus during recent years. The most important dissolution fluids to carbonates are probably H2S and CO2 as byproducts of sulfate reduction in deep-buried setting with sulfate minerals, but carbonates are more soluble in relatively low temperature, which is the so-called retrograde solubility. Several geological processes can result in the decrease of temperature, including the upward migration of thermal fluids and tectonic uplift.

Experimental and modelling study of the solubility of CO_2 in various CaCl_2 solutions at different temperatures and pressures

Study of the thermodynamic behaviour of CaCl2-H2O-CO2 systems is important in different scientific areas in the chemical and petroleum engineering fields. For example, a system including salt- H20-CO2 is a common system in CO2 geological storage. During carbonate matrix acidizing, this mixture also appears as the spent acid. Hence, study of the behaviour of this system and the solubility of CO2 in CaCl2 brine in different thermodynamic conditions is critical. In this study, CO2 solubility in 0, 1.90 and 4.80 mol/L CaCl2 solutions at 328.15 to 375.15 K and 68.9 to 206.8 bar were measured. These values are normal for oil reservoirs. A popular thermodynamic model is available in the literature for estimating the CO2 solubility in pure water and NaC1 solutions. In this paper, the available model was modified by experimental work to be applicable for CaCl2 as well. Based on the measured data, the component interaction parameters in the base model were adjusted for a CaCl2-H2O-CO2 system. The developed model could predict CO2 solubility in different conditions with remarkable accuracy, particularly for high concentration solutions and at high pressures. This improvement is up to 65% better than in the base model. This model can be used in Darcy scale models for predicting wormhole propagation during carbonate matrix acidizing.

Determination and correlation solubility of 4-nitroimidazole in twelve pure solvents from 278.15 K to 323.15 K

In this paper,the solubility of 4-nitroimidazole in twelve pure solvents(toluene,benzene,1,4-dioxane,acetonitrile,ethyl acetate,acetone,GBL,ethanol,methanol,n-butanol,DMF and NMP)were determined by using the laser monitoring system from 278.15 K to 323.15 K under 101.1 k Pa,which are 0.00018–0.00070,0.00021–0.00073,0.00034–0.00092,0.00038–0.00142,0.00047–0.00120,0.00126–0.00303,0.00225–0.00517,0.00310–0.00724,0.00467–0.00982,0.00453–0.01940,0.01947–0.04652,and 0.04670–0.07452,respectively.At constant temperature,the mole fraction solubility of 4-nitroimidazole were increased as the following order:toluene<benzene<1,4-dioxane<(ethyl acetate or acetonitrile)<acetone<GBL<ethanol<(methanol or nbutanol)<DMF<NMP,and the solubility of 4-nitroimidazole in(ethyl acetate,acetonitrile)and(methanol,n-butanol)had an intersection point at 297.55 K and 281.85 K,respectively.The solubility of 4-nitroimidazole could be increased with increasing temperature in twelve pure solvents.The ideal model,modified Apelblat equation,polynomial empirical equation,andλh equation were used to correlate the experimental values.The experimental solubility values were employed to calculate the standard dissolution enthalpy,standard dissolution entropy and Gibbs energy.The dissolution of 4-nitroimidazole could be an endothermic process in twelve pure solvents.The determination and fitting solubility of 4-nitroimidazole have important guiding significance for the purification and crystallization of its preparation process.

Crystallization thermodynamics of 2,4(5)-dinitroimidazole in binary solvents

2,4(5)-Dinitroimidazole(2,4(5)-DNI)is an important organic intermediate,and itself can also be used for energetic material.In this work,the solubility of 2,4(5)-DNI in(methanol+water,acetonitrile+water,acetone+water)binary solvents were measured by using a dynamic test method from 278.15 K to 323.15 K under 101.1 k Pa.The Jouyban–Acree model,van't Hoff–Jouyban–Acree model,Apelblat–Jouyb an–Acree model,Ma model,and Sun model were used to correlate the experimental data.The values of relative average deviation(RAD)and root-mean-square deviation(RMSD)were very small,indicating that the error between the experimental value and the correlated value was very small.The thermodynamic parameters such as dissolution enthalpy,dissolution entropy and Gibbs energy were calculated based on solubility data.High-purity of 2,4(5)-DNI was efficiently obtained by using cooling and dilution crystallization method.

Crystallization thermodynamics of 2,4(5)-dinitroimidazole in eleven pure solvents

2,4(5)-Dinitroimidazole(2,4(5)-DNI) is an important energetic material, and it is also an important precursor for the preparation of drugs and energetic materials. In this study, the solubility of 2,4(5)-DNI in eleven pure solvents(chlorobenzene, benzene, 1,2-dichloroethane, toluene, water, isopropyl alcohol,ethyl acetate, acetonitrile, methanol, 1,4-dioxane and acetone) were measured by using a dynamic test method from 278.15 K to 323.15 K under 101.1 kPa. Four solubility models were used to fit the experimental data, which were ideal model, modified Apelblat equation, polynomial empirical equation, and λh equation. Meanwhile, the relative average deviation and root-mean-square deviation between the experimental data and the fitted data were also calculated. Furthermore, the three thermodynamic parameters,i.e., dissolution enthalpy, dissolution entropy and Gibbs energy were obtained based on solubility data.Finally, the crude product of 2,4(5)-DNI was crystallized with acetone as solvent, and the purity of the crystalline product was greater than 99.5%.