Alkylation waste sulfuric acid resource recycling method

Abstract

A method for recycling waste sulfuric acid from alkylation, comprising the following steps: (1) mixed impregnation: mixed impregnation according to the liquid-solid weight ratio of waste sulfuric acid and condensation carbonization agent of 1:1-10:1; (2) condensation carbonization Reaction: The waste sulfuric acid after mixing and impregnation and the condensation carbonization agent are subjected to condensation carbonization reaction at a temperature of 95-145°C and a pressure of normal pressure-0.05MPa for 1-10 minutes to obtain carbides and waste liquid; (3) Washing: put The carbides are washed countercurrently for many times, and after filtration and separation, the carbides and filtrate are finally obtained; (4) Decolorization and deodorization: add decolorization and deodorization agent according to 1-10% of the weight of the filtrate, and decolorize and deodorize at a temperature of 50-100°C , recycling to obtain regenerated sulfuric acid; (5) carbon material recovery: the carbide obtained in step (3) is used for fuel or further processed into activated carbon. The method of the invention is carried out under relatively small pressure and low temperature when processing waste sulfuric acid from alkylation, the device has mild operating conditions, low energy consumption, low investment, simple operation and low device maintenance cost.

Description

technical field [0001] The present invention relates to a resource recovery method of high-concentration sulfuric acid containing organic and inorganic impurities, more specifically, it relates to the resource recovery of waste catalyst-waste sulfuric acid produced during the production of high-octane alkylate oil method. Background technique [0002] At present, in the process of petroleum refining, concentrated sulfuric acid is usually used as a catalyst in the process of alkylating low-carbon hydrocarbon molecules to produce high-octane alkylated petroleum. In the process, the moisture and side reaction products in the raw materials continue to enter the concentrated sulfuric acid catalyst, and the sulfuric acid concentration gradually decreases. When the concentrated sulfuric acid concentration is lower than 90%, it loses its activity, and the waste sulfuric acid is discharged to form alkylation waste sulfuric acid. About 80-100 kg of waste sulfuric acid is produced in ...

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Problems solved by technology

And this treatment method needs redox reaction at 150°C~250°C, the material of the reactor is selected from tantalum material, titanium material, lined with glass fiber reinforced plastic or quartz glass, but the inventor found during the experiment that at 150-250°C Many materials cannot withstand the corrosion of concentrated sulfuric acid at high temperatures, such as tantalum: tantalum can be corroded in hot concentrated sulfuric acid, and tantalum will not be corroded by concentrated sulfuric acid below 150°C, only at high temperatures Only at this temperature will there be a reaction. In concentrated sulfuric acid at 175°C for one year, the corroded thickness is 0.0004mm; if tantalum is soaked in sulfuric acid at 200°C for one year, the surface layer will only be damaged by 0.006mm; at 250°C, The corrosion rate has increased, and the corroded thickness is 0.116 mm per year; at 300 ° C, the corroded rate is even faster, and the surface is corroded by 1.368 mm after soaking for 1 year; another example is titanium: titanium is resistant to low temperature and low concentration. The concentration of sulfuric acid has a certain corrosion resistance. At 0°C, it can withstand the corrosion of sulfuric acid with a concentration of 20%. With the increase of acid concentration and temperature, the corrosion rate increases, so the stability of titanium in sulfuric acid is poor, even At room temperature of dissolved oxygen, titanium can only resist 5% sulfuric acid corrosion, and at 100°C, titanium can only resist corrosion at a concentration of 0.12%. Corrosion at 100°C, and the temperature rises, the corrosion intensifies; concentrated sulfuric acid has strong oxidizing and dehydrating properties to carbonize FRP, and the FRP material will become soft and leaky after a period of use; therefore, the use of the above materials at 150-250°C and normal The oxidation-reduction reaction at a pressure as high as 5.0MPa is likely to cause damage to the equipment and seriously affect the normal operation of the equipment. In this way, it will not only cause acid leakage and increase unsafe factors, but also require a lot of manpower, Putting material resources into production will further affect the efficiency of the factory and increase production costs