CN102773116A - Method for preparing catalyst capable of promoting ammonia nitrogen conversion in chemical wastewater - Google Patents
Method for preparing catalyst capable of promoting ammonia nitrogen conversion in chemical wastewater Download PDFInfo
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- CN102773116A CN102773116A CN2012102531932A CN201210253193A CN102773116A CN 102773116 A CN102773116 A CN 102773116A CN 2012102531932 A CN2012102531932 A CN 2012102531932A CN 201210253193 A CN201210253193 A CN 201210253193A CN 102773116 A CN102773116 A CN 102773116A
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Abstract
The invention discloses a method for preparing catalyst capable of promoting ammonia nitrogen conversion in chemical wastewater. The method includes the following steps of proportionally weighing argil, zeolite, silica gel and graphite as adsorbent carriers after drying and smashing, proportionally weighing and mixing lead oxide, vanadium oxide, chromic oxide, copper oxide and the like to obtain maceration extract, macerating the same volume of adsorbent carriers in the maceration extract for 11 to 17 hours, drying, roasting, and reducing by hydrogen to obtain the catalyst, and the obtained catalyst is filled into an ammonia distillation tower as filler. The filler 3cm to 5cm in thickness for each layer is filled in the ammonia distillation tower for every 50cm till a tower top. By the aid of the catalyst, the temperature of steam in a normal pressure condition can be utilized to directly convert ammonia in the chemical wastewater into nitrogen to be exhausted to the atmosphere, so that secondary pollution is avoided, high temperature pressurization is needless, cost is low, and ammonia nitrogen removing rate is high.
Description
Technical field
The present invention relates to a kind of method for preparing catalyst that promotes that ammonia nitrogen transforms in the wastewater from chemical industry, belong to sewage treatment area.
Background technology
In recent years; Along with expanding economy, heavy industry such as oil, chemical industry development is rapid, and the various places chemical enterprise is gushed out like the mushrooms after rain; Thing followed air, water pollution problems are also paid attention to by people day by day, and the high ammonia-nitrogen wastewater that produces therefrom also becomes one of industry development restraining factors.And in order to keep sustained development of enterprises, the waste that reduces water resource with environmental pollution, improve business economic benefit and society's effect, it is imperative that wastewater from chemical industry is carried out advanced treating.
And it is at present varied to the processing of ammonia nitrogen waste water; In " ammonia nitrogen in the Co/Bi catalyst wet oxidation degraded rubbish infiltration filtrating " literary composition that proposes by Jilin University's environment and resource institute; Its adopts the CWCO technology, be that catalyst is degraded to ammonia nitrogen with Co/Bi; Along with the rising of temperature, CWCO strengthens the degradation capability of NH3-N gradually under high pressure 0.5～2.0MPa condition, in temperature-rise period (20～300 ℃); NH3-N oxidized gradually degraded has reached the CWCO technology purpose of degradation of organic substances and NH3-N simultaneously.In addition; The technology of utilizing the ammonia still process method to remove wastewater from chemical industry middle and high concentration ammonia nitrogen neither not have; Such as publication number is CN102351265A; Name is called in " a kind of coking production remained ammonia negative pressure ammonia distillation process and device " disclosed method and in desulfurizing tower ammonia vapour porch a Venturi tube is set in advance, and distilled ammonia wastewater/cyclic ammonia water heat exchanger and distilled ammonia wastewater circulating pump are set at the bottom of ammonia still; Open heat exchanger and circulating pump then; The heat of cyclic ammonia water is brought in the ammonia still by distilled ammonia wastewater; When the ammonia still process tower top temperature reaches 60～80 ℃, open into Venturi tube doctor solution pipeline valve, ammonia vapour is sucked desulfurizing tower; Open remained ammonia pump and distilled ammonia wastewater pump afterwards, remaining ammoniacal liquor is got into the ammonia still processing through heat exchanger get final product.
Yet in the method for more than enumerating, the former needs the condition of HTHP; Operating cost is high, though the latter under steam condition, just can transform nitrogen to ammonia; But still there is weak point: 1,,, cause product impure because of containing multiple other materials because the discharging meeting of ammonia causes secondary pollution 2, adopts the processing method that absorbs the ammonia that emits environment; And concentration is not high, can not satisfy the produce market demand.
Summary of the invention
Need when the catalysis condition of HTHP could ammonia changed into the expensive problem of nitrogen and combine the ammonia still process blow-off method to cause secondary pollution problem to air with catalyst to above prior art; Provide a kind of and just can promote that in the ammonia still process process wastewater from chemical industry middle and high concentration ammonia nitrogen changes into the Preparation of Catalyst and the application process thereof of nitrogen; The present invention utilizes the temperature of steam that the ammonia in the waste water is directly changed into nitrogen discharge in atmosphere; Avoided secondary pollution problem; And need not pressurization, cost is low, and ammonia nitrogen removal frank is high.
In order to achieve the above object, the technical scheme of taking is:
A kind of method for preparing catalyst that promotes that ammonia nitrogen transforms in the wastewater from chemical industry is characterized in that:
(1) carrier preliminary treatment: count by ratio of weight and the number of copies, get 30 parts of potter's clay, 20 parts of zeolites, 25 parts of silica gel, 25 parts of graphite through oven dry, pulverizing, grind into powder, as adsorbing agent carrier;
(2) maceration extract configuration: be made into mass concentration and be respectively 10～30g/L plumbi nitras, 5～8g/L vanadic sulfide, 5～7g/L chromium sulfate, 1～2g/L copper nitrate, 5～6g/L mercuric nitrate, 4～5g/L caddy, 5～9g/L nickel chloride, 3～5g/L titanium chloride, 2～4g/L thorium nitrate, 2～4g/L cobalt chloride, 25～30g/L malic acid, 8～11g/L tolysulfonyl hydrazine solution;
(3) dipping: flooded 11～17 hours according to carrier and maceration extract equal-volume (V);
(4) dry, roasting: drying is 11～17 hours under the vacuum normal temperature condition, again 110 ℃ of dryings 6 hours in baking oven; In negative pressure is that 0.3MPa, temperature are roasting 3 hours under 700 ℃ of conditions, is rapid cool drying under 0.5MPa, the normal temperature condition in negative pressure then, can obtain the cellular catalyst that contains various heavy;
(5) activation: under the nitrogen protection condition, under 900 ℃ of conditions, feed hydrogen reducing.
The described cellular catalyst that contains multiple precious metal is counted with the oxide mass ratio:
The invention has the beneficial effects as follows:
(1) can directly be reduced into nitrogen discharge to the ammonia nitrogen in the wastewater from chemical industry, can not cause secondary pollution environment;
(2) solve catalyst not needing to be reduced into nitrogen under ultra-high temperature and the pressure condition, practiced thrift cost;
(3) to the water quality situation of wastewater from chemical industry, selected with the plumbi nitras to be main catalyst, with strong points.
The specific embodiment:
The described cellular catalyst that contains multiple precious metal is counted with the oxide mass ratio:
20～30g lead oxide, 6～8g vanadium oxide, 6～7g chromium oxide,
1～2g cupric oxide, 5～6g mercury oxide, 16～18g cadmium oxide,
15～16g nickel oxide, 4～9g titanium oxide, 9～11g thorium oxide,
1～4g ruthenium-oxide.
At first; Taking by weighing 30 parts of potter's clay, 20 parts of zeolites, 25 parts of silica gel and 25 parts of graphite mixes after dry, pulverize grind into powder as adsorbing agent carrier; Get 10～30g/L plumbi nitras, 5～8g/L vanadic sulfide, 5～7g/L chromium sulfate, 1～2g/L copper nitrate, 5～6g/L mercuric nitrate, 4～5g/L caddy, 5～9g/L nickel chloride, 3～5g/L titanium chloride, 2～4g/L thorium nitrate, 2～4g/L cobalt chloride, 25～30g/L malic acid, 8～11g/L tolysulfonyl hydrazine solution then and be made into maceration extract; Then according to carrier and maceration extract incipient impregnation 11～17 hours; Again under condition of normal pressure, after dry 11～17 hours in baking oven under 110 ℃ of conditions dry 6 hours; Be that 0.3MPa, temperature are roasting 3 hours under 700 ℃ the condition then in negative pressure; Be rapid cool drying under 0.5MPa, the normal temperature condition in negative pressure again; Can obtain the cellular catalyst that contains various heavy, under the nitrogen protection condition, in 900 ℃ temperature, feed hydrogen reducing afterwards.Place the catalyst that makes in the ammonia still as filler at last, depth of packing is 3～5cm, and every separated 50cm lays one deck, until cat head.
Instance 1:
The described cellular catalyst that contains multiple precious metal is counted with the oxide mass ratio:
30g lead oxide, 6g vanadium oxide, 6g chromium oxide,
1g cupric oxide, 5g mercury oxide, 16g cadmium oxide,
15g nickel oxide, 4g titanium oxide, 9g thorium oxide,
The 1g ruthenium-oxide.
At first; Taking by weighing 30 parts of potter's clay, 20 parts of zeolites, 25 parts of silica gel and 25 parts of graphite mixes after dry, pulverize grind into powder as adsorbing agent carrier; Get 30g/L plumbi nitras, 5g/L vanadic sulfide, 7g/L chromium sulfate, 1g/L copper nitrate, 5g/L mercuric nitrate, 5g/L caddy, 5g/L nickel chloride, 3g/L titanium chloride, 2g/L thorium nitrate, 2g/L cobalt chloride, 25g/L malic acid, 10g/L tolysulfonyl hydrazine solution then and be made into maceration extract; Then according to carrier and maceration extract incipient impregnation 11 hours; Again under condition of normal pressure, after dry 11 hours in baking oven under 110 ℃ of conditions dry 6 hours; Be that 0.3MPa, temperature are roasting 3 hours under 700 ℃ the condition then in negative pressure; Be rapid cool drying under 0.5MPa, the normal temperature condition in negative pressure again; Can obtain the cellular catalyst that contains various heavy, under the nitrogen protection condition, in 900 ℃ temperature, feed hydrogen reducing afterwards.Place the catalyst that makes in the ammonia still as filler at last, depth of packing is 3cm, and every separated 50cm lays one deck, until cat head.
Gather the waste water sample of Changzhou drugmaker; Utilize the catalyst of processing by said method that the ammonia nitrogen in the waste water is handled then; Ammonia nitrogen concentration after handling in this waste water is reduced to 0.2mg/L from 10000mg/L, and ammonia nitrogen removal frank is 99.98%, simultaneously; Recording airborne NH3 content is 1.1mg/m3, reaches national ammonia secondary discharge standard.
Instance 2:
The described cellular catalyst that contains multiple precious metal is counted with the oxide mass ratio:
20g lead oxide, 8g vanadium oxide, 7g chromium oxide,
2g cupric oxide, 6g mercury oxide, 18g cadmium oxide,
16g nickel oxide, 9g titanium oxide, 11g thorium oxide,
The 3g ruthenium-oxide.
At first; Taking by weighing 30 parts of potter's clay, 20 parts of zeolites, 25 parts of silica gel and 25 parts of graphite mixes after dry, pulverize grind into powder as adsorbing agent carrier; Get 30g/L plumbi nitras, 8g/L vanadic sulfide, 7g/L chromium sulfate, 2g/L copper nitrate, 6g/L mercuric nitrate, 5g/L caddy, 9g/L nickel chloride, 5g/L titanium chloride, 4g/L thorium nitrate, 4g/L cobalt chloride, 30g/L malic acid, 10g/L tolysulfonyl hydrazine solution then and be made into maceration extract; Then according to carrier and maceration extract incipient impregnation 17 hours; Again under condition of normal pressure, after dry 17 hours in baking oven under 110 ℃ of conditions dry 6 hours; Be that 0.3MPa, temperature are roasting 3 hours under 700 ℃ the condition then in negative pressure; Be rapid cool drying under 0.5MPa, the normal temperature condition in negative pressure again; Can obtain the cellular catalyst that contains various heavy, under the nitrogen protection condition, in 900 ℃ temperature, feed hydrogen reducing afterwards.Place the catalyst that makes in the ammonia still as filler at last, depth of packing is 5cm, and every separated 50cm lays one deck, until cat head.
Gather the waste water sample of Wuxi pharmaceutical factory; Utilize the catalyst of processing by said method that the ammonia nitrogen in the waste water is handled then; Ammonia nitrogen concentration after handling in this waste water is reduced to 0.2mg/L from 15000mg/L, and ammonia nitrogen removal frank is 99.99%, simultaneously; Recording airborne NH3 content is 1.0mg/m3, reaches national ammonia first discharge standard.
Instance 3:
25g lead oxide, 7g vanadium oxide, 7g chromium oxide,
2g cupric oxide, 5g mercury oxide, 17g cadmium oxide,
16g nickel oxide, 8g titanium oxide, 10g thorium oxide,
The 3g ruthenium-oxide.
At first; Taking by weighing 30 parts of potter's clay, 20 parts of zeolites, 25 parts of silica gel and 25 parts of graphite mixes after dry, pulverize grind into powder as adsorbing agent carrier; Get 20g/L plumbi nitras, 6g/L vanadic sulfide, 6g/L chromium sulfate, 1g/L copper nitrate 6g/L mercuric nitrate, 4g/L caddy, 8g/L nickel chloride, 4g/L titanium chloride, 3g/L thorium nitrate, 3g/L cobalt chloride, 27g/L malic acid, 9g/L tolysulfonyl hydrazine solution then and be made into maceration extract; Then according to carrier and maceration extract incipient impregnation 14 hours; Again under condition of normal pressure, after dry 15 hours in baking oven following dry 6 hours of 110 ℃ of conditions; Be that 0.3MPa, temperature are roasting 3 hours under 700 ℃ the condition then in negative pressure; Be rapid cool drying under 0.5MPa, the normal temperature condition in negative pressure again; Can obtain the cellular catalyst that contains various heavy, under the nitrogen protection condition, in 900 ℃ temperature, feed hydrogen reducing afterwards.Place the catalyst that makes in the ammonia still as filler at last, depth of packing is 4cm, and every separated 50cm lays one deck, until cat head.
Gather the waste water sample of Shanghai pharmaceutical factory; Utilize the catalyst of processing by said method that the ammonia nitrogen in the waste water is handled then; Ammonia nitrogen concentration after handling in this waste water is reduced to 0.2mg/L from 18000mg/L, and ammonia nitrogen removal frank is 99.99%, simultaneously; Recording airborne NH3 content is 1.0mg/m3, reaches national ammonia first discharge standard.
Claims (2)
1. method for preparing catalyst that promotes that ammonia nitrogen in the wastewater from chemical industry transforms is characterized in that:
(1) carrier preliminary treatment: count by ratio of weight and the number of copies, get 30 parts of potter's clay, 20 parts of zeolites, 25 parts of silica gel, 25 parts of graphite through oven dry, pulverizing, grind into powder, as adsorbing agent carrier;
(2) maceration extract configuration: be made into mass concentration and be respectively 10～30g/L plumbi nitras, 5～8g/L vanadic sulfide, 5～7g/L chromium sulfate, 1～2g/L copper nitrate, 5～6g/L mercuric nitrate, 4～5g/L caddy, 5～9g/L nickel chloride, 3～5g/L titanium chloride, 2～4g/L thorium nitrate, 2～4g/L cobalt chloride, 25～30g/L malic acid, 8～11g/L tolysulfonyl hydrazine solution;
(3) dipping: flooded 11～17 hours according to carrier and maceration extract equal-volume (V);
(4) dry, roasting: drying is 11～17 hours under the vacuum normal temperature condition, again 110 ℃ of dryings 6 hours in baking oven; In negative pressure is that 0.3MPa, temperature are roasting 3 hours under 700 ℃ of conditions, is rapid cool drying under 0.5MPa, the normal temperature condition in negative pressure then, can obtain the cellular catalyst that contains various heavy;
(5) activation: under the nitrogen protection condition, under 900 ℃ of conditions, feed hydrogen reducing.
2. a kind of method for preparing catalyst that promotes that ammonia nitrogen transforms in the wastewater from chemical industry according to claim 1, it is characterized in that: the described cellular catalyst that contains multiple precious metal is counted with the oxide mass ratio:
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104148089A (en) * | 2014-07-18 | 2014-11-19 | 常州大学 | Preparation and application method of high-concentration ammonia nitrogen catalyst in papermaking wastewater |
| CN104229970A (en) * | 2014-08-26 | 2014-12-24 | 常州大学 | Device for treating high-concentration ammonia nitrogen in refinery wastewater by using surface activity catalyst |
| CN106669735A (en) * | 2016-12-27 | 2017-05-17 | 常州大学 | Catalyst for enhancing ammonia conversion in domestic wastewater, and application method thereof |
| CN107096498A (en) * | 2017-05-02 | 2017-08-29 | 杭州师范大学 | A kind of modified zeolite ball preparation method and application |
| CN109647466A (en) * | 2017-10-12 | 2019-04-19 | 中国石油化工股份有限公司 | Catalyst for inclined acid anhydride synthetic reaction |
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| JPS5460290A (en) * | 1977-10-21 | 1979-05-15 | Nippon Steel Corp | Production of catalyst for removing nitrogen oxide from exhaustion gas producted in ammonia contact reducing system |
| CN1838989A (en) * | 2003-09-27 | 2006-09-27 | 韩国电力技术株式会社 | Vanadium/titania-based catalyst for removing nitrogen oxide at low temperature window, and process of removing nitrogen oxide using the same |
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2012
- 2012-07-18 CN CN201210253193.2A patent/CN102773116B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5460290A (en) * | 1977-10-21 | 1979-05-15 | Nippon Steel Corp | Production of catalyst for removing nitrogen oxide from exhaustion gas producted in ammonia contact reducing system |
| CN1838989A (en) * | 2003-09-27 | 2006-09-27 | 韩国电力技术株式会社 | Vanadium/titania-based catalyst for removing nitrogen oxide at low temperature window, and process of removing nitrogen oxide using the same |
Non-Patent Citations (2)
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| 尹奋平等: "粘土矿物在废水处理中的应用", 《水处理技术》, vol. 31, no. 5, 31 May 2005 (2005-05-31), pages 1 - 6 * |
| 李晔等: "沸石改性及其对氨氮废水处理效果的研究", 《非金属矿》, vol. 26, no. 2, 31 March 2003 (2003-03-31), pages 53 - 55 * |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104148089A (en) * | 2014-07-18 | 2014-11-19 | 常州大学 | Preparation and application method of high-concentration ammonia nitrogen catalyst in papermaking wastewater |
| CN104148089B (en) * | 2014-07-18 | 2016-02-10 | 常州大学 | A kind of preparations and applicatio method of Processing Paper Wastewater middle and high concentration ammonia nitrogen catalyst |
| CN104229970A (en) * | 2014-08-26 | 2014-12-24 | 常州大学 | Device for treating high-concentration ammonia nitrogen in refinery wastewater by using surface activity catalyst |
| CN106669735A (en) * | 2016-12-27 | 2017-05-17 | 常州大学 | Catalyst for enhancing ammonia conversion in domestic wastewater, and application method thereof |
| CN107096498A (en) * | 2017-05-02 | 2017-08-29 | 杭州师范大学 | A kind of modified zeolite ball preparation method and application |
| CN107096498B (en) * | 2017-05-02 | 2019-09-10 | 杭州师范大学 | A kind of modified zeolite ball preparation method and application |
| CN109647466A (en) * | 2017-10-12 | 2019-04-19 | 中国石油化工股份有限公司 | Catalyst for inclined acid anhydride synthetic reaction |
| CN109647466B (en) * | 2017-10-12 | 2020-10-16 | 中国石油化工股份有限公司 | Catalyst for synthesis reaction of partial anhydride |
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| CN102773116B (en) | 2014-05-07 |
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