METHOD OF TREATING SPENT ACID AFTER ALKYLATION AND DEVICE FOR IMPLEMENTING SAID METHOD Russian patent published in 2020 - IPC C01B17/27 C01B17/04 C01B17/90 C01B17/80 B01J23/88 B01J21/04 B01J21/06 F23G5/00 

FIELD: chemistry.

SUBSTANCE: present description relates to chemical industry and particularly to a device for treating spent acid after alkylation. Method of treating spent sulphuric acid after alkylation involves the following steps: step I: combustion of reducing acid gases and spent sulphuric acid after alkylation in an atmosphere containing oxygen to obtain sulphur tail gases; stage II: lowering the temperature of sulphur tail gases for cooling gaseous elementary sulphur substance contained in sulphur tail gases to a liquid elemental sulphur and separating said liquid elemental sulphur; and step III: conversion of sulphur-containing compounds contained in gases obtained at stage II into elemental sulphur and separation of said elementary sulphur substance from gases; where conversion is carried out in a group of converters comprising: a first-stage converter successively filled with a protective layer of catalyst containing molybdenum oxide and/or nickel oxide as an active component, a first catalyst layer for regenerating sulphur, comprising an aluminium oxide as an active component, second catalyst layer for sulphur recovery containing TiO₂ and Al₂O₃ as active components and an iron salt and/or silicate as an additive, and a distribution layer formed from porcelain balls and a metal mesh; wherein protective layer of catalyst, catalyst first layer for sulphur regeneration and second catalyst layer for sulphur regeneration are 5–30 %, 0–90 % and 5–95 % by volume of protective layer of catalyst, first layer of catalyst for regeneration of sulphur and second layer of catalyst for regeneration of sulphur, respectively; and a secondary converter filled with a first catalyst bed for regenerating sulphur, wherein the first catalyst support layer for sulphur regeneration is used to convert SO₂, H₂S and organic sulphur contained in tail gases into elemental sulphur substance, and second catalyst layer for sulphur regeneration is used to convert SO₂, H₂S and organic sulphur into elementary sulphur substance and for decomposition of SO₃ to SO₂ and O₂. Device for carrying out the above-described method of treating spent sulphuric acid after alkylation comprises: a combustion assembly comprising a burner and a spent acid spray gun, connected to the burner, where spent acid spray gun has a spray nozzle and a gun body having an inlet for spent acid along the first direction and an air inlet along a second direction intersecting with the first direction; and a sulphur separation unit located downstream of the burner and connected to the burner, where said device is configured to burn the spent acid in the burner in a reducing acidic atmosphere to form sulphur tail gases, from which sulphur is separated in form of an elementary sulphur substance using the sulphur recovery unit; where the sulphur extraction unit comprises a sulphur condenser connected to the burner and a group of converters connected to the sulphur condenser, and where sulphur condenser is configured to cool gaseous elementary sulphur substance in sulphur tail gases to liquid elemental sulphur and to recover said liquid elemental sulphur, wherein the group of converters is configured to convert sulphur-containing compounds contained in gases leaving the sulphur condenser into a basic sulphur substance and separating said elemental sulphur.

EFFECT: method of treating spent acid after alkylation and apparatus for realizing said method are disclosed.

23 cl, 6 ex, 10 dwg