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The objective of the research was to evaluate the potential of refractory chromites from Victoria I deposit (in Camagüey, Cuba) as a source of chromium for producing electrodes to recharge parts by manual electric arc welding. A mixture of rutile, graphite, refractory chromite, sodium silicate and AISI 1009 steel rods was used as raw material. The experimental electrodes were obtained by pressing the coating from a dosed mixture with the previous components. The mass balance predicts the weld bead can be alloyed with carbon and chromium by introducing refractory chromite and graphite in the rutile coating. The experimental results corroborated that the welding process allowed obtaining 2.3% carbon and 2.89% chromium in the metal deposited by the experimental electrodes. Results show that refractory chromites from Camagüey constitute a potential source of chromium for manufacturing rutile-coated electrodes for recharging parts by manual electric arc welding.

The objective of the research was to evaluate the potential of refractory chromites from Victoria I deposit (in Camagüey, Cuba) as a source of chromium for producing electrodes to recharge parts by manual electric arc welding. A mixture of rutile, graphite, refractory chromite, sodium silicate and AISI 1009 steel rods was used as raw material. The experimental electrodes were obtained by pressing the coating from a dosed mixture with the previous components. The mass balance predicts the weld bead can be alloyed with carbon and chromium by introducing refractory chromite and graphite in the rutile coating. The experimental results corroborated that the welding process allowed obtaining 2.3% carbon and 2.89% chromium in the metal deposited by the experimental electrodes. Results show that refractory chromites from Camagüey constitute a potential source of chromium for manufacturing rutile-coated electrodes for recharging parts by manual electric arc welding. [ABSTRACT FROM AUTHOR]

Se evaluó la posibilidad de utilización de la zeolita de Palmarito de Cauto (Santiago de Cuba) para el tratamiento del licor residual de la industria de fibrocemento. Dos clases granulométricas de zeolita (A: granos entre 1 mm y 2 mm y B: granos entre 3 mm y 5 mm) se pusieron en contacto con muestras del residual con el fin de remover de este el cromo disuelto y evaluar el efecto sobre la basicidad (pH) del licor. Se pudo constatar la capacidad de la zeolita para remover el cromo disuelto, mayoritariamente en forma de Cr (VI) (iones cromato), y en menor cantidad, como Cr (III). La remoción de Cr (VI) ocurrió a través de un proceso de adsorción y la del Cr (III) por intercambio iónico. Se obtuvo la disminución del pH del residual desde valores superiores a 12 hasta cercanos a 7 unidades. Esto permite sugerir el empleo de la zeolita de Palmarito para remover el cromo y ajustar el pH del licor residual de la industria de fibrocemento hasta valores normados para su vertimiento o reutilización industrial

El licor WL es un residual de la industria del níquel agresivo al medio ambiente por su acidez que contiene elementos metálicos de gran valor. Se propone un tratamiento para la separación con hidróxido de amonio y la recuperación de la mayor cantidad de cromo y aluminio contenidos en el mismo. Se logra precipitar una mezcla de hidróxidos de aluminio que tratada con ácido sulfúrico permite obtener, por cristalización, la sal sulfato de aluminio y amonio dodecahidratada. Posteriomente se cristaliza la sal sulfato doble de cromo y amonio dodecahidratado. Se demuestra que el sulfato doble de cromo y amonio dodecahidratado y el sólido separado presentan características químicas que hacen posible su aplicación en la industria textil y de cerámica, entre otras. El esquema aplicado permite la recuperación de valores metálicos y la disminución del alto poder contaminante del licor de desecho WL.

The WL liquor is a residual from de nickel industry containing valorous metallic elements and impacting the environment by its acidity. Proposed is a treatment, using ammonium hydroxide to separate and recover the most part of chromium and aluminium contained in it. It is achieved the precipitation of a mixture of aluminum and chromium hydroxide, which undergoes treatment with sulfuric acid lead to obtain, by crystallization, the salt aluminum sulfate and ammonium dodecahydrated. Later by treatment with ammonium hydroxide and pH adjustment, crystallized is the double salt sulphate of chromium and ammonium dodecahydrated. The carried out study demonstrates that the double sulfate of chromium and ammonium dodecahydrated and the separated solid, have chemical characteristic that allow its possible application in the textile and ceramic industries. The applied treatment permits to recover metallic elements and to reduce the pollution of the environment. [ABSTRACT FROM AUTHOR]