Conductance Studies of Aqueous Succinic Acid

1992 ◽  
Vol 47 (3) ◽  
pp. 493-498 ◽  
Author(s):  
Alexander Apelblat ◽  
Josef Barthel

Abstract Conductance measurements of aqueous solutions of succinic acid and of di-sodium succinate were performed from 278.15 to 308.15 K and the limiting conductances λ0 (1/2 Succ2- ) are reported. The Waiden product is independent of temperature: λ0(1/2 Succ2-)*η(T) = 0.503 ± 0.001. The salt conductances closely obey the Onsager limiting law. The evaluation of the equilibrium constants for the primary and secondary steps of dissociation, K1 and K2, and the limiting conductances of the hydrosuccinate ion, λ0(HSucc-), are discussed using the Quint and Viallard conductance equation

2014 ◽  
Vol 16 (2) ◽  
pp. 1-4 ◽  
Author(s):  
Jerzy Antczak ◽  
Justyna Regiec ◽  
Krystyna Prochaska

Abstract This paper applies the determined suitability of nanofiltration (NF) membrane separation for selective isolation and concentration of succinic acid from aqueous solutions which are post-fermentation multicomponent fluids. The study analyzed the influence of concentration and the pH of the separated solutions on the efficiency and selectivity of NF process that runs in a module equipped with a ceramic membrane. Moreover, the effect of applied trans-membrane pressure on the retention of succinic acid and sodium succinate has been studied. The investigations have shown that in the used NF module the retention of succinic acid salt is equal almost 50% in the case of a three-component model solution, although the degree of retention depends on both the transmembrane pressure and the initial concentration of separated salt.


1980 ◽  
Vol 45 (10) ◽  
pp. 2645-2655 ◽  
Author(s):  
Antonín Mikan ◽  
Miloš Bartušek

The reactions of sorbitol, mannitol, adonitol, dulcitol, glucose and glycerol with H3AsO4, H3AsO3, H3BO3 and GeO2 acids in dilute aqueous solutions were studied by potentiometric neutralization titrations. The formation of the following chelates was demonstrated: As(V)L3-, As(III)L(OH)2-, HAs(III)L(OH)2, BL2-, GeL2(OH)- and GeL32- and the equilibrium constants for their formation were found. Conditions for formation of these chelates of organic oligohydroxy compounds are discussed.


1895 ◽  
Vol 37 (2) ◽  
pp. 361-379
Author(s):  
A. Crum Brown ◽  
James Walker

In our former paper we described the results obtained by electrolysing concentrated aqueous solutions of the ethyl-potassium salts of normal saturated dibasic acids. The chief products were shown to be diethyl compound ethers of the same homologous series, and the formation of these compound ethers was shown to occur in accordance with the equation: 2C2H5·O·ĊO·R˝·CO·O- = C2H5·O·CO·R˝R˝CO·O·C2H5 + 2CO2. We now find that precisely similar results are obtained by electrolysing the corresponding compounds derived from saturated dibasic acids with side chains. We have thus been able to effect the synthesis of acids of the succinic acid series, in which hydrogen is symmetrically replaced by alcohol radicals of the form CnH2n+1.


The method of pH-potentiometric titration and mathematical simulation were used to study the equilibrium processes in aqueous solutions of the WO42––CH3COOH–H2O system in the acidity range Z=(CH3COOH)/(Na2WO4)=0.8–1.7 at СW=0.01 mol L–1 and T=2980.1 K, a constant ionic strength being maintained by sodium nitrate as a background electrolyte ((NaNO3)=0.10 mol L–1). We developed the models of polyoxotungstate anions formation and the equilibrium transformation processes, which adequately describe experimental pH vs. Z dependences. It was found that acetic acid using to create the solution acidity that is necessary for the formation of isopoly tungstate anion contributes only to the formation of protonated paratungstate B anions Нх[W12O40(ОН)2](10–х)– (where x=0–4). We calculated the logarithms of the concentration equilibrium constants of the polyanion formation and plotted the distribution diagrams. Double sodium-manganese(II) paratungstate B Na8(H2O)28Mn(H2O)2[H2W12O42]4H2O was synthesized at Z=1.00 to confirm the results of the mathematical modeling. The chemical composition of the prepared salt was established by chemical elemental analysis, thermal analysis, FTIR spectroscopy, and single crystal X-ray analysis. The stepwise process of salt dehydration was studied by means of differential thermal analysis.


1987 ◽  
Vol 65 (12) ◽  
pp. 2824-2829 ◽  
Author(s):  
Peter Taylor ◽  
Vincent J. Lopata

Observations are reported on the interconversion of solid α-Bi2O3, Bi12O17Cl2, BiOCl, and a daubréeite-like phase tentatively identified as Bi2O2(OH)Cl, in aqueous chloride solutions at 25 °C. Equilibrium constants, K, for these interconversions are expressed as anion activity ratios, {Cl−}/{OH−}. Experimental values of K for equilibrium between Bi2O3 and each of the chlorides are 100.56 ± 0.20 for Bi12O17Cl2, 101.5 ± 0.4 for Bi2O2(OH)Cl, and 103.13 ± 0.04 for BiOCl; the fatter two represent metastable equilibria. These equilibrium constants yielded the following estimates of Gibbs energies of formation: Bi12O17Cl2, −3141 ± 6 kJ mol−1;"Bi2O2(OH)Cl", −696 ± 4 kJ mol−1; BiOCl, −321.5 ± 1.3 kJ mol−1. Phase relationships among these solids are discussed, with reference to natural occurrence, other bismuth oxychlorides, and the stability of other basic salts of bismuth.


1989 ◽  
Vol 44 (4) ◽  
pp. 465-474 ◽  
Author(s):  
Armand Blaschette ◽  
Karin Linoh ◽  
Dietrich Koch ◽  
Ludger Ernst

N, N, N′, N′ -Tetramesyl dicarboxylic diamides Ms2NC(O)-Q-C(O)NMs2 [Q = (CH2)n with n = 0 (2a), 2 (2b), 3 (2c), 4 (2d); Q = o-phenylene (2e)] were prepared by reacting AgNMs2 (1) with the appropriate dicarboxylic dichlorides in acetonitrile at room temperature (2a, 2 c-2e) or at 0 °C (2b), respectively. Under similar conditions, malonic dichloride undergoes an elimination, forming AgCl, HNMs2 and probably polymeric C3O2. At 20 °C in CH3CN, the succinic acid derivative 2b eliminates one mole of HNMs2 and, by ring closure, yields γ-dimesylamino-Δβγ- butenolide (4a), the first example of a stable γ-amino-Δβγ-butenolide. Treatment of 4a with aqueous NaOH results in the formation of NaNMs2 and sodium succinate. Crystalline 4a is thermally stable at 100 °C; no signs of an isomerization 4a → γ-dimesylamino-Δαγ-butenolide could be detected. Unlike the structurally related α-angelicalactone (4c), whose bromination affords the saturated dibromolactone 9 as a mixture of cis- and mws-isom ers, 4a adds bromine (20 °C, CHCl3) under ring cleavage to form BrC(O)CH2CHBrC(O)NMs2 (7). The new compounds 2, 4a and 7 as well as the stereoisomers of 9 were characterized by spectroscopic (1H and 13C NMR, MS, IR) and analytical methods. In order to obtain reference values for the chemical shifts of 7, the following new compounds were prepared: CH3(CH2)2C(O)NMs2 (10c, from 1 and butvryl chloride); CH3CH2CHBrC(O)NMs2 (12c, from 1 and 2-bromobutyryl bromide); C2H5OC(O)CH 2CHBrC(O)NMs2 (13, from 7 with ethanol and from 4a by simultaneous reaction with bromine and ethanol).


1962 ◽  
Vol 40 (3) ◽  
pp. 363-372 ◽  
Author(s):  
R. W. Burley ◽  
W. H. Cook

The effect of pH, temperature, ionic strength, and lipoprotein concentration on the reversible dissociation of α- and β-lipovitellin in aqueous solutions above pH 6 has been examined by ultracentrifugal measurements. Under otherwise similar conditions α- and β-lipovitellin are 50% dissociated at pH 10.5 and 7.8, respectively. Both lipovitellins undergo an irreversible aggregation above about pH 11; β-lipovitellin is sometimes converted to a non-dissociable form upon aging. Dissociation of both lipovitellins decreases with increasing ionic strength and increasing temperature. Although the ultracentrifugal method has limitations, provisional equilibrium constants and thermodynamic data were obtained from it that are comparable with those obtained for certain protein systems.


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