Precipitation and Solubility of Calcium Hydrogenurate Hexahydrate
نویسندگان
چکیده
Solid phases formed in the quaternary system: uric acid-calcium hydroxide -hydrochloric acid-water aged for 2 months at 310 K were studied to determine conditions for calcium hydrogenurate hexahydrate, Ca(C5H3N4O)2 · 6H2O precipitation. The precipitates were identified by chemical and thermogravimetric analyses, x-ray powder diffraction, infrared spectroscopy, light microscopy, and scanning electron microscopy. In the precipitation diagram the concentration region in which calcium hydrogenurate hexahydrate precipitated as a single solid phase was established. The solubility of calcium hydrogenurate hexahydrate was investigated in the pH range from 6.2 to 10.1 at different temperatures. The total soluble and ionic concentration of calcium (atomic absorption spectroscopy and Ca-selective electrode), total urate concentration (spectrophotometry), and pH were determined in equilibrated solutions. The data are presented in the form of tables and chemical potential diagrams. By using these data the thermodynamic solubility products of calcium hydrogenurate hexahydrate, Ks = a(Ca2+) · a2(C5H3N4O3-), were determined: [Formula: see text]The formation of calcium hydrogenurate hexahydrate crystals in urinary tract of patients with pathologically high concentrations of calcium and urates (hypercalciuria and hyperuricosiuria) is possible.
منابع مشابه
Influence of pH, temperature and common ion on magnesium hydrogenurate octahydrate solubility.
Physico-chemical investigation of urolithiasis today is mostly focused on applying physico-chemical description of precipitation processes to the stone formation with the aim to distinguish between stone formers and nonstone formers. This is done by calculating supersaturation for different solid phases which can be formed in urine using data obtained by urine analysis and existing solubility p...
متن کاملAnaerobic digestion of dairy manure with enhanced ammonia removal.
Poor ammonia-nitrogen removal in methanogenic anaerobic reactors digesting animal manure has been reported as an important disadvantage of anaerobic digestion (AD) in several studies. Development of anaerobic processes that are capable of producing reduced ammonia-nitrogen levels in their effluent is one of the areas where further research must be pursued if AD technology is to be made more eff...
متن کاملA thermodynamic solution model for calcium carbonate: Towards an understanding of multi-equilibria precipitation pathways.
Thermodynamic solubility calculations are normally only related to thermodynamic equilibria in solution. In this paper, we extend the use of such solubility calculations to help elucidate possible precipitation reaction pathways during the entire reaction. We also estimate the interfacial energy of particles using only solubility data by a modification of Mersmann's approach. We have carried th...
متن کاملEffect of various electrolytes on control release of bio-molluscicides loaded in alginate as crosslinked matrices
Background and Objective: To assess the control release of bio-molluscicides (Crude Ferula asafoetida and their active component ferulic acid) loaded in alginates as binding matrix. Methodology: Sodium alginate, an anionic block copolymer of β-D-mannuronic acid and α-L-guluronic acid, is a readily available, non-toxic polysaccharide its property to form gel with divalent and multivalent cations...
متن کاملChemical precipitation and characterization of multicomponent Perovskite Oxide nanoparticles – possible cathode materials for low temperature solid Oxide fuel cell
A set of multicomponent perovskite oxide nanoparticles based on La1-xSrxCo1-yFeyO3-δ(LSCF) were prepared by a simple chemical precipitation method for application in low temperature solid oxide fuel cells (LT-SOFC) as cathode materials. The precursor materials used in this synthesis were lanthanum nitrate hexahydrate [La(NO3)<su...
متن کامل