A method for recovering platinum group metals from spent auto catalysts

Abstract

The invention discloses a method for recycling platinum group metal from ineffective automobile catalysts. The method includes the steps of (1) mechanical activation, (2) high-temperature roasting, (3) ball-milling water immersion, (4) diluted acid leaching and (5) platinum group metal refining. Platinum group metal enriched products obtained in the step (4) are processed according to existing refining processes, so that platinum group metal products are obtained. The ineffective automobile catalysts are processed through the method of combining mechanical activation, sodium salt roasting, water immersion and acid leaching, the reaction activity of materials is improved through mechanical activation, phase transformation of catalyst carrier components occurs due to sodium salt roasting, insoluble residues are enriched with the platinum group metal after water immersion and acid leaching, and separation between carriers and the platinum group metal is achieved. Equipment needed for the method is conventional metallurgical equipment, the technological process is simple, industrial implementation is easy, and the total recovery rate of the platinum group metal is larger than 98%.

Description

technical field

[0001] The invention relates to the field of secondary resource recovery of platinum group metals, in particular to a method for recovering platinum group metals from an exhausted automobile catalyst. Background technique

[0002] my country's platinum group metal mineral resources are very poor, and the prospective reserves are less than 350 tons. At present, my country is in a period of rapid economic development, and the consumption of platinum group metals is increasing year by year. It has become the world's largest consumer of platinum group metals. In 2012, my country's annual demand for platinum group metals reached about 140 tons, accounting for about 20% of the world's total. According to statistics, my country's automobile production in 2011 was 18 million. With the failure of catalysts and the scrapping of automobiles, the spent catalysts replaced each year contain 25-40 tons of platinum group metals. As the service life of catalysts reaches its ...

Examples

Embodiment 1

[0016] Embodiment 1, see attached figure 1 , take 500g of expired auto catalyst broken into 1mm (wherein SiO 2 About 40%, Al 2 o 3 About 35%, MgO about 10%, Pt 357g / t, Pd 963g / t, Rh 193g / t), mixed with 1kg sodium carbonate and 30g sodium borate, placed in a stirring mill for mechanical activation for 30min; the activated mixed material Place in an iron crucible and roast at 1300°C for 3 hours; place the roasted product in a wet ball mill for ball mill water immersion (conditions: pulp concentration 20%, initial water temperature 90°C, time 1h), after solid-liquid separation, hot water Washing; then the water-insoluble slag is leached with dilute acid (conditions: sulfuric acid mass concentration is 25%, room temperature, leaching time 2h, liquid-solid ratio 8), after solid-liquid separation, the platinum group metal enrichment is obtained, which is used Platinum group metals are dissolved, separated and purified to obtain platinum, palladium and rhodium metal products, and...

Embodiment 2

[0017] Embodiment 2, see attached figure 1 , take 500g of expired auto catalyst broken into 1mm (wherein SiO 2 About 40%, Al 2 o 3 About 35%, MgO about 10%, Pt 357g / t, Pd 963g / t, Rh 193g / t), mixed with 1kg sodium carbonate and 50g sodium borate, placed in a stirring mill for mechanical activation for 30min; the activated mixed material Place in an iron crucible and roast at 1250°C for 3 hours; place the roasted product in a wet ball mill for ball mill water immersion (conditions: pulp concentration 15%, initial water temperature 90°C, time 1h), after solid-liquid separation, hot water Washing; then the water-insoluble slag is leached with dilute acid (conditions: the mass concentration of sulfuric acid is 25%, room temperature, leaching time 2h, liquid-solid ratio 6), after solid-liquid separation, the platinum group metal enrichment is obtained, which is used in the present Platinum group metals are dissolved, separated and purified to obtain platinum, palladium and rhodi...

Embodiment 3

[0018] Embodiment 3, see attached figure 1 , take 500g of spent auto catalyst finely ground to 100 mesh (wherein SiO 2 About 40%, Al 2 o 3 About 35%, MgO about 10%, Pt 357g / t, Pd 963g / t, Rh 193g / t), mixed with 1.5kg sodium carbonate and 50g sodium borate, placed in a stirring mill for mechanical activation for 30min; the activated mixture The material was placed in an iron crucible and roasted at 1200°C for 3 hours; the roasted product was placed in a wet ball mill for ball milling and water immersion (conditions: pulp concentration 20%, initial water temperature 90°C, time 0.5h), after solid-liquid separation, Washing with hot water; then leaching the water-insoluble slag with dilute acid (conditions: sulfuric acid mass concentration is 20%, room temperature, leaching time 3h, liquid-solid ratio 8), after solid-liquid separation, the platinum group metal enrichment is obtained, and its The existing platinum group metal dissolution, separation and purification process is u...

technical field

[0001] The invention relates to the field of secondary resource recovery of platinum group metals, in particular to a method for recovering platinum group metals from an exhausted automobile catalyst. Background technique

[0002] my country's platinum group metal mineral resources are very poor, and the prospective reserves are less than 350 tons. At present, my country is in a period of rapid economic development, and the consumption of platinum group metals is increasing year by year. It has become the world's largest consumer of platinum group metals. In 2012, my country's annual demand for platinum group metals reached about 140 tons, accounting for about 20% of the world's total. According to statistics, my country's automobile production in 2011 was 18 million. With the failure of catalysts and the scrapping of automobiles, the spent catalysts replaced each year contain 25-40 tons of platinum group metals. As the service life of catalysts reaches its ...

Examples

Embodiment 1

[0016] Embodiment 1, see attached figure 1 , take 500g of expired auto catalyst broken into 1mm (wherein SiO 2 About 40%, Al 2 o 3 About 35%, MgO about 10%, Pt 357g / t, Pd 963g / t, Rh 193g / t), mixed with 1kg sodium carbonate and 30g sodium borate, placed in a stirring mill for mechanical activation for 30min; the activated mixed material Place in an iron crucible and roast at 1300°C for 3 hours; place the roasted product in a wet ball mill for ball mill water immersion (conditions: pulp concentration 20%, initial water temperature 90°C, time 1h), after solid-liquid separation, hot water Washing; then the water-insoluble slag is leached with dilute acid (conditions: sulfuric acid mass concentration is 25%, room temperature, leaching time 2h, liquid-solid ratio 8), after solid-liquid separation, the platinum group metal enrichment is obtained, which is used Platinum group metals are dissolved, separated and purified to obtain platinum, palladium and rhodium metal products, and...

Embodiment 2

[0017] Embodiment 2, see attached figure 1 , take 500g of expired auto catalyst broken into 1mm (wherein SiO 2 About 40%, Al 2 o 3 About 35%, MgO about 10%, Pt 357g / t, Pd 963g / t, Rh 193g / t), mixed with 1kg sodium carbonate and 50g sodium borate, placed in a stirring mill for mechanical activation for 30min; the activated mixed material Place in an iron crucible and roast at 1250°C for 3 hours; place the roasted product in a wet ball mill for ball mill water immersion (conditions: pulp concentration 15%, initial water temperature 90°C, time 1h), after solid-liquid separation, hot water Washing; then the water-insoluble slag is leached with dilute acid (conditions: the mass concentration of sulfuric acid is 25%, room temperature, leaching time 2h, liquid-solid ratio 6), after solid-liquid separation, the platinum group metal enrichment is obtained, which is used in the present Platinum group metals are dissolved, separated and purified to obtain platinum, palladium and rhodi...

Embodiment 3

[0018] Embodiment 3, see attached figure 1 , take 500g of spent auto catalyst finely ground to 100 mesh (wherein SiO 2 About 40%, Al 2 o 3 About 35%, MgO about 10%, Pt 357g / t, Pd 963g / t, Rh 193g / t), mixed with 1.5kg sodium carbonate and 50g sodium borate, placed in a stirring mill for mechanical activation for 30min; the activated mixture The material was placed in an iron crucible and roasted at 1200°C for 3 hours; the roasted product was placed in a wet ball mill for ball milling and water immersion (conditions: pulp concentration 20%, initial water temperature 90°C, time 0.5h), after solid-liquid separation, Washing with hot water; then leaching the water-insoluble slag with dilute acid (conditions: sulfuric acid mass concentration is 20%, room temperature, leaching time 3h, liquid-solid ratio 8), after solid-liquid separation, the platinum group metal enrichment is obtained, and its The existing platinum group metal dissolution, separation and purification process is u...

Images