3results about How to "Precipitation complete" patented technology

The invention provides a method for measuring the content of rhodium in a platinum-rhodium alloy, which comprises the following steps: completely dissolving the platinum-rhodium alloy, then mixing and reacting with nitrite, adjusting the pH value, and carrying out solid-liquid separation to obtain a platinum-rhodium mixed solution; and mixing the platinum-rhodium mixed solution with a coordination precipitator and a polar solvent in sequence, carrying out solid-liquid separation to obtain rhodium precipitate, and calculating the rhodium content in the platinum-rhodium alloy according to the mass of the rhodium precipitate. According to the determination method, measurement errors caused by introduction of metal impurities in the platinum-rhodium alloy are avoided, trace residues of rhodium precipitates in the solution and co-precipitation of other interference metals are also avoided, procedures and used reagents are simple, operation is safe, efficiency is high, use of high-cost and complex precipitants such as metal elementary substances or cobalt hexammine nitrate in the prior art is avoided, and the method is suitable for large-scale popularization and application. Rhodium precipitation is complete, the determination result is accurate, the relative standard deviation is especially smaller than 0.21%, meanwhile, dependence on expensive analysis equipment is not needed, and the method has great application value.

This application relates to a silicon-modified macroporous pseudoboehmite and its preparation method, belonging to the technical field of pseudoboehmite preparation. The method includes: mixing an aluminum salt solution and a sodium aluminate solution in parallel flow and performing a low-temperature neutralization reaction; adding a low-concentration water glass 5-8 minutes after the start of the reaction, ensuring the water glass addition ends before the neutralization reaction ends, to obtain an amorphous precursor; separating the amorphous precursor into a liquid and solid state to obtain a filter cake; mixing the filter cake with deionized hydrated slurry to obtain a slurry; adding sodium carbonate to the slurry to adjust the pH to 8-9 to obtain an alkaline slurry; subjecting the alkaline slurry to an aging and crystallization reaction at high temperature to obtain a pseudoboehmite slurry; filtering and washing the pseudoboehmite slurry to obtain a silicon-modified macroporous pseudoboehmite filter cake, and then drying it to obtain silicon-modified macroporous pseudoboehmite.

The utility model provides pickling wastewater treatment equipment, which relates to the technical field of stainless steel pickling wastewater treatment and comprises a treatment box provided with a liquid inlet channel and a liquid outlet channel. The device further comprises a non-contact liquid level sensor, an electronic prompting piece, a stirring assembly, an alkali liquor adding assembly, a flocculating agent adding assembly, a pH value detection assembly, a first limiting frame, a filtering assembly, a temporary storage assembly, a first telescopic cylinder, a circulation channel, a second limiting frame and a screening piece. According to the device, the filtering piece and the screening piece can be conveniently replaced on the basis of treating the acid wastewater, so that the stable treatment effect of the acid wastewater is ensured, and meanwhile, the pH value can be accurately obtained in the neutralization and heavy metal precipitation processes of the acid wastewater, so that heavy metal is completely precipitated; after the heavy metal precipitate is generated, a flocculating agent is added to promote the heavy metal precipitate to coagulate into large flocs, and finally the electromagnetic valve is opened to separate the heavy metal precipitate, namely effective solid-liquid separation.