Method for preparing hydrogen cyanide desorption catalyst by using combined supercritical carbon dioxide/supercritical hydrothermal method

Abstract

The invention discloses a method for preparing a hydrogen cyanide desorption catalyst by using combined supercritical carbon dioxide / supercritical hydrothermal methods and belongs to the technical field of industrial waste gas purification. The method comprises the following steps: by taking a transition metal salt as a precursor of an active component, mixing the active component precursor solution with a carrier, performing contact soaking in supercritical carbon dioxide, and synthesizing a carried type catalyst by using a supercritical hydrothermal method. Compared with a conventional soaking method, the supercritical carbon dioxide soaking method is short in soaking time and uniform in active component distribution; due to supercritical hydrothermal reactions, separation and carrying of the active component on the surface of the carrier can be rapidly completed, and in addition, the dispersity of the active component is further improved; the carried type catalyst prepared by usingthe combined supercritical carbon dioxide / supercritical hydrothermal methods has relatively high desorption efficiency upon hydrogen cyanide.

Description

technical field

[0001] The invention relates to a method for preparing a catalyst for removing hydrogen cyanide by using a supercritical carbon dioxide / supercritical hydrothermal combined method, and belongs to the technical field of industrial waste gas purification. Background technique

[0002] Hydrogen cyanide is a highly toxic substance and one of the most typical "unconventional" toxic and harmful pollutants in industrial waste gas. Hydrogen cyanide is a highly toxic gas that poses a huge threat to human health and the ecological environment, and its toxicity is 35 times that of carbon monoxide. Its poisoning mechanism is similar to carbon monoxide, CN - Fe in human body and oxidative cytochrome oxidase in mitochondria 3+ binding, thereby preventing the Fe 3+ The reduction of oxygen makes the cells and tissues unable to use oxygen, causing the human body to be hypoxic and suffocate. In addition, hydrogen cyanide is highly corrosive and toxic in the industrial produ...

Examples

Embodiment 1

[0017] Embodiment 1: a kind of method utilizing supercritical carbon dioxide / supercritical hydrothermal combined method to prepare dehydrogenation cyanide catalyst, concrete steps are as follows:

[0018] (1) Dissolve the active component precursor (the active component precursor is copper nitrate) in solvent A (solvent A is water) to prepare an active component impregnation solution with a concentration of 1mol / L;

[0019] (2) Add the impurity-removed carrier (the carrier is activated carbon) and the impregnation solution of active components obtained in step (1) into the reaction kettle, heat up to the supercritical state of carbon dioxide and impregnate for 10 minutes to obtain the pretreatment reaction system, open the pressure relief valve, quickly reduce the pressure and collect carbon dioxide; the temperature of the supercritical state of carbon dioxide is 40°C, and the pressure is 10MPa; the solid-liquid ratio g:mL of the carrier (activated carbon) and the active compon...

Embodiment 2

[0022] Embodiment 2: a kind of method utilizing supercritical carbon dioxide / supercritical hydrothermal combined method to prepare dehydrogenation catalyst, concrete steps are as follows:

[0023] (1) Dissolve the active component precursor (the active component precursor is iron acetate) in solvent A (solvent A is ethanol) to prepare an active component impregnation solution with a concentration of 5mol / L;

[0024] (2) Add the impurity-removed carrier (the carrier is carbon black) and the active component impregnation liquid obtained in step (1) into the reaction kettle, heat up to the supercritical state of carbon dioxide and impregnate for 15 minutes to obtain pretreatment In the reaction system, open the pressure relief valve, quickly reduce the pressure and collect carbon dioxide; the temperature of the supercritical state of carbon dioxide is 50 ° C, and the pressure is 7.3 MPa; the solid-liquid ratio g:mL of the carrier (carbon black) and the active component impregnatio...

Embodiment 3

[0027] Embodiment 3: a kind of method utilizing supercritical carbon dioxide / supercritical hydrothermal combined method to prepare dehydrogenation catalyst, concrete steps are as follows:

[0028] (1) Dissolve the active component precursor (the active component precursor is copper chloride) in solvent A (solvent A is methanol) to prepare an active component impregnation solution with a concentration of 10mol / L;

[0029] (2) Add the impurity-removed carrier (carrier is activated carbon fiber) washed with water, and the impregnated liquid of the active component obtained in step (1) into the reaction kettle, heat up to the supercritical state of carbon dioxide by feeding in carbon dioxide, and impregnate for 30 minutes to obtain pretreatment In the reaction system, open the pressure relief valve, quickly reduce the pressure and collect carbon dioxide; the temperature of the supercritical state of carbon dioxide is 55 ° C, and the pressure is 8.5 MPa; the solid-liquid ratio g:mL ...

technical field

[0001] The invention relates to a method for preparing a catalyst for removing hydrogen cyanide by using a supercritical carbon dioxide / supercritical hydrothermal combined method, and belongs to the technical field of industrial waste gas purification. Background technique

[0002] Hydrogen cyanide is a highly toxic substance and one of the most typical "unconventional" toxic and harmful pollutants in industrial waste gas. Hydrogen cyanide is a highly toxic gas that poses a huge threat to human health and the ecological environment, and its toxicity is 35 times that of carbon monoxide. Its poisoning mechanism is similar to carbon monoxide, CN - Fe in human body and oxidative cytochrome oxidase in mitochondria 3+ binding, thereby preventing the Fe 3+ The reduction of oxygen makes the cells and tissues unable to use oxygen, causing the human body to be hypoxic and suffocate. In addition, hydrogen cyanide is highly corrosive and toxic in the industrial produ...

Examples

Embodiment 1

[0017] Embodiment 1: a kind of method utilizing supercritical carbon dioxide / supercritical hydrothermal combined method to prepare dehydrogenation cyanide catalyst, concrete steps are as follows:

[0018] (1) Dissolve the active component precursor (the active component precursor is copper nitrate) in solvent A (solvent A is water) to prepare an active component impregnation solution with a concentration of 1mol / L;

[0019] (2) Add the impurity-removed carrier (the carrier is activated carbon) and the impregnation solution of active components obtained in step (1) into the reaction kettle, heat up to the supercritical state of carbon dioxide and impregnate for 10 minutes to obtain the pretreatment reaction system, open the pressure relief valve, quickly reduce the pressure and collect carbon dioxide; the temperature of the supercritical state of carbon dioxide is 40°C, and the pressure is 10MPa; the solid-liquid ratio g:mL of the carrier (activated carbon) and the active compon...

Embodiment 2

[0022] Embodiment 2: a kind of method utilizing supercritical carbon dioxide / supercritical hydrothermal combined method to prepare dehydrogenation catalyst, concrete steps are as follows:

[0023] (1) Dissolve the active component precursor (the active component precursor is iron acetate) in solvent A (solvent A is ethanol) to prepare an active component impregnation solution with a concentration of 5mol / L;

[0024] (2) Add the impurity-removed carrier (the carrier is carbon black) and the active component impregnation liquid obtained in step (1) into the reaction kettle, heat up to the supercritical state of carbon dioxide and impregnate for 15 minutes to obtain pretreatment In the reaction system, open the pressure relief valve, quickly reduce the pressure and collect carbon dioxide; the temperature of the supercritical state of carbon dioxide is 50 ° C, and the pressure is 7.3 MPa; the solid-liquid ratio g:mL of the carrier (carbon black) and the active component impregnatio...

Embodiment 3

[0027] Embodiment 3: a kind of method utilizing supercritical carbon dioxide / supercritical hydrothermal combined method to prepare dehydrogenation catalyst, concrete steps are as follows:

[0028] (1) Dissolve the active component precursor (the active component precursor is copper chloride) in solvent A (solvent A is methanol) to prepare an active component impregnation solution with a concentration of 10mol / L;

[0029] (2) Add the impurity-removed carrier (carrier is activated carbon fiber) washed with water, and the impregnated liquid of the active component obtained in step (1) into the reaction kettle, heat up to the supercritical state of carbon dioxide by feeding in carbon dioxide, and impregnate for 30 minutes to obtain pretreatment In the reaction system, open the pressure relief valve, quickly reduce the pressure and collect carbon dioxide; the temperature of the supercritical state of carbon dioxide is 55 ° C, and the pressure is 8.5 MPa; the solid-liquid ratio g:mL ...