Sodium dichromate

About: Sodium dichromate is a research topic. Over the lifetime, 421 publications have been published within this topic receiving 6202 citations. The topic is also known as: Disodium salt & sodium bichromate.

Preparation method of passivant for automobile powdered metal part

Abstract: The invention discloses a preparation method of a passivant for an automobile powdered metal part. The preparation method comprises the step that water, sodium dichromate, glycidol, ludox, para toluic acid, sodium hydroxide, light calcium carbonate, an acrylic emulsion, magnesium oxide, cellulose nitrate, polyvinyl alcohol, potassium phosphate, sodium carbonate, 2-methylimidazole and dibutyl phthalate are weighed. The preparation method is simple, low in cost, high in operability, free of pollution to the environment, safe, environmentally friendly, resistant to acid and alkali and excellent in moisture resistance; a product with a film formed is high in strength, the adhesive force is 1 level, the corrosion resistance is good, heat shock resistance is achieved, the impact strength is 60-100 J, the viscosity is 65-85 s, and the adhesiveness is 250-290; the process stability is good, the service life is long, no remarkable change occurs after 6-10 years after the film is formed, using is easy, the film is firm and resistant to abrasion, the glossiness is good, the 60-degree glossiness is 92-98%, and the flexibility is 1 mm; and a finished product is atoxic, the hardness is 5-9, no wastewater is discharged, and sources of raw materials are extensive.

Some Transformative Reactions of Odollactone

Abstract: Oxidative rearrangement of odollactone has been carried out with hydrogen peroxide containing p-toluene sulphonic acid in dichloromethane. The products obtained were characterised by chemical transformation using selenium dioxide in acetic acid, sodium dichromate in acetic acid and Li in ethylenediamine followed by spectral analysis. The in- troduction of olefinic double bond at AB-ring juncture influences the cleavage of γ-lactone ring to the diol in contrast to the parent odollactone that gives the carboxylic acid.

Oxidation of Halides, Ethers, Acetals, Sulphides, and Some Nitrogen Containing Compounds

Abstract: The direct conversion of alkyl halides into the corresponding carbonyl compounds, despite its potential interest for organic synthesis, is seldomly referred to in the literature. Only few examples of the oxidation of benzylic halides with aqueous acidic chromic acid or with aqueous sodium dichromate and alkali hydroxides [1] under rather drastic conditions have been reported. A preparatively useful example is the oxidation of α-chlorohydrindene to a-hydrindanone in 50–60% yield by means of chromic acid in aqueous acetic acid at 40 °C [2]: Open image in new window

Exploration of croconic acid disodium salt as an organic battery electrode material

Abstract: We investigated croconic acid disodium salt for potential use as Li-ion battery material. The crystal was shown to be a promising electrode material with a medium to short battery cycle lifetime. We embarked in a thorough computational study based on classical molecular dynamics simulations to characterize this system and identify optimization strategies to improve battery lifetime. Through long-timescale molecular dynamics simulations in the Canonical Ensemble and Isothermal-Isobaric ensembles, we first established that the custom force field that we generated for this system reproduces the known thermodynamics of the Croconic acid disodium salt dihydrate crystal. In a second step, we predict the existence of a quasi-degenerate denser polymorph which is slightly less stable at room temperature and becomes more stable starting T=420K compared to the known crystal structure as determined by X-Ray crystallography. Interestingly, we find that upon adding lithium the system chooses the denser phase even at room temperature. Lithiation of the denser phase leads to moderate volume increases of about 0.75% for each additional 1% lithiation. By extrapolation of the results of the simulations, we conjecture that a phase transition takes place in the very first stages of lithiation. This should initially reduce the volume, resulting in the formation of cracks in the material contributing to a short battery cycle lifetime. We thus propose to assemble batteries based on croconate at an elevated temperature.