Hydrometallurgical process for extracting bismuth from by-product of lead smelting based on methanesulfonic acid system

A new hydrometallurgical process based on the methanesulfonic acid system was proposed to extract the bismuth efficiently from by-products of lead smelting.The bismuth extraction process included electrorefining,oxidation leaching,and electrodeposition.The optimum conditions of the bismuth extraction process were determined by a single-factor test.The bismuth plate with a purity of 99.8%was obtained under the optimum conditions.Cyclic voltammetry and linear sweep voltammetry were applied to investigating the cathode reaction mechanism of electrorefining.The results show that lead deposition,bismuth deposition,and hydrogen evolution occur at the cathode,and the reactions of metals deposition are irreversible and diffusion-controlled.In addition,decreasing the temperature and acidity can improve the purity of the cathodic product(lead powder)in the electrorefining process.

Methanesulfonic acid sodium salt protects retina from acute light damage in mice

Background Methanesulfonic acid sodium salt （Dipyrone）, an antipyretic and analgesic drug, has been demonstrated to improve cerebral ischemia through the inhibition of mitochondrial cell death cascades. The aim of this study was to evaluate the potential photoprotective activity of methanesulfonic acid sodium salt in a model of light-induced retinopathy. Methods One hundred mice were assigned randomly into vehicle （V）, methanesulfonic acid sodium salt （D）, light damage model plus vehicle （MV） and light damage model plus methanesulfonic acid sodium salt （MD） groups （n=25 each）. In the MD group, methanesulfonic acid sodium salt （100 mg/kg） was administered by intraperitoneal injection 30 minutes before light exposure. Twenty-four hours after light exposure, hematoxylin and eosin staining and transmission electron microscopy （TEM） were used for histological evaluation. The thickness of the outer plus inner-segment and outer nuclear layer was measured on sections parallel to the vertical meridian of the eye at a distance of 1000 I^m from the optic nerve. Electroretinography （ERG） test was performed to assess the functional change. The morphology of mitochondria was also revealed by TEM. Finally, the expression of cytochrome c （CytC） and the relative apoptotic proteins were detected by Western blotting, and the interaction between mitochondrial proteins was investigated by co-immunoprecipitation. Results The photoreceptor inner and outer segments of the MV group were significantly disorganized than the MD group. The thicknesses of the outer plus inner-segment layers and the outer nuclear layer, and the amplitudes of the a and b waves of the scotopic ERG response markedly decreased in the MV group compared to those in the MD group （P 〈0.05）. TEM examination revealed that the mitochondria of the MV group were distinctly swollen and contained disrupted cristae. In contrast, the morphology of mitochondria in the MD group was unaffected. Western blotting analysis showed that CytC, apoptosis proteinase activating factor-1 （Apaf-1）, caspase 3, p53, p53-upregulated modulator of apoptosis （PUMA）, Bax, and Bad were increased, whereas the anti-apoptotic proteins Bcl-2 and Bcl-XL were significantly decreased in the MV group than the MD group. Co-immunoprecipitation detection revealed that PUMA immunoreactivity precipitated by Bcl-XL decreased, whereas Bax immunoreactivity precipitated by Bcl-XL increased in the MD group compared to those in the MV group. Conclusion Methanesulfonic acid sodium salt is an effective photoprotective agent against light-induced retinopathy through the inhibition of CytC-mediated mitochondrial impairment.

Silica Supported Methanesulfonic Acid as an Efficient and Reusable Heterogeneous Catalyst for the Synthesis of Amidoalkyl Naphthols

A green protocol for the preparation of amidoalkyl naphthols from three-component one-pot condensation of 2-naphthol, aldehydes, amides or urea in the presence of silica supported methanesulfonic acid under thermal sol- vent-free conditions has been described. The catalyst is stable, efficient, easily prepared, and reusable. The remarkable features of this methodology are short reaction time, excellent yields, simple experimental and work-up procedures.

A novel method to anchor methanesulfonic acid in silica matrix

Methanesulfonic acid （MSA） was successfully immobilized in silica, leading to a novel and environmentally friendly solid acid catalyst SMSA. The most important feature of SMSA is that anhydrous formic acid is used to hydrolysis of tetraethylorthosili- cate （TEOS）. No water was added in the whole preparation. Therefore, MSA could be anchored in silica matrix more effec- tively instead of being dissolved in water. This new organic/inorganic hybrid catalyst was characterized by powder X-ray dif- fraction （XRD）, energy dispersive spectrum （EDS）, N2 adsorption-desorption analyzer, thermogravimetric analysis （TGA-DSC） and pyridine-FTIR. The catalytic activity was tested by alkylation of olefins and aromatics. High concentration acid sites, both Lewis and Brcnsted, abundant porosity and large surface area enabled the highest activity for SMSA, among MCM-22. ZSM-5 and industrial acidity clay.

A novel preparation method of sulfonic functionalized silica： CH3SO3H as the sulfonic source and Al as the bridge

A novel approach is designed to optimize the synthesis of sulfonic-functionalized silica material. Results from 29Si and 27AI NMR suggest that the AI acts as the bridging atom connecting the methanesulfonate and silica matrix. Further pyridine-FTIR spectra followed by catalytic activity tests demonstrate that compared with previous methods, our new approach results in higher Lewis acid site concentration, higher thermal stability and superior catalytic activity. Moreover, the whole catalysis preparation procedure is environmentally friendly. Specifically, the silica matrix is synthesized through hydrolysis of tetrae- thylorthosilicate employing formic acid as hydro-catalyst, in which no surfactant species or precursors were involved.