Method for the point of use production of ammonia from water and nitrogen
The present invention discloses a method for the manufacture of high purity ammonia, hydrogen, and nitrogen from de-ionized water and standard nitrogen. De-ionized water is degassed and fed to an electrolytic hydrogen generator to produce raw hydrogen. The hydrogen is purified and mixed with purified nitrogen, compressed, and fed to a catalytic ammonia reactor. Following purification, the ammonia is delivered to the semiconductor process tool along with purified hydrogen and purified nitrogen.
1 . A method for producing ammonia gas from liquid water and nitrogen, comprising the steps of:
feeding a quantity of de-ionized water to a hydrogen generator;
producing a quantity of hydrogen from the quantity of de-ionized water utilizing said hydrogen generator;
producing a quantity of purified hydrogen by passing said quantity of hydrogen through a hydrogen purifier;
producing a quantity of purified nitrogen by passing a quantity of nitrogen through a nitrogen purifier; and,
contacting said quantity of purified hydrogen and said quantity of purified nitrogen with a catalyst bed, wherein a portion of said purified hydrogen and a portion of said purified nitrogen react to form a quantity of ammonia.
2 . The method as recited in claim 1 , further comprising the step of:
de-gassing said quantity of de-ionized water prior to feeding the de-ionized water to said hydrogen generator, to remove a portion of dissolved gasses in said quantity of de-ionized water.
3 . The method as recited in claim 2 , wherein said quantity of de-ionized water is de-gassed in a membrane contactor, having a first stage followed by a second stage.
4 . The method as recited in claim 3 , wherein in said first stage, a first portion of said dissolved gassed are removed by nitrogen stripping.
5 . The method as recited in claim 3 , wherein in said second stage, a second portion of said dissolved gasses are removed by vacuum stripping.
6 . The method as recited in claim 1 , further comprising the step of:
compressing said quantity of purified hydrogen and said quantity of purified nitrogen prior to contacting said quantity of purified hydrogen and said quantity of purified nitrogen with said catalyst bed.
7 . The method as recited in claim 6 , wherein said quantity of purified hydrogen and said quantity of purified nitrogen are compressed to a pressure between 10 and 100 atmospheres, absolute.
8 . The method as recited in claim 1 , further comprising the step of:
producing a quantity of purified ammonia by passing said quantity of ammonia through an ammonia purifier.
9 . The method as recited in claim 8 , further comprising the step of:
delivering a portion of said quantity of purified ammonia to a semiconductor process tool.
10 . The method as recited in claim 8 , wherein said ammonia purifier comprises a high surface area metal oxide comprising oxides of barium, calcium, iron, lithium, manganese, molybdenum, potassium, rhenium, sodium, strontium, titanium, tungsten, and vanadium.
11 . The method as recited in claim 8 , wherein at least one of said ammonia purifier, said hydrogen purifier, and said nitrogen purifier are regenerated with a portion of said quantity of purified hydrogen.
12 . The method as recited in claim 8 , wherein the concentration of an impurity in said quantity of purified ammonia is reduced to less than 50 ppb.
13 . The method as recited in claim 8 , wherein the concentration of an impurity in said quantity of purified ammonia is reduced to less than 10 ppb.
14 . The method as recited in claim 1 , wherein said hydrogen purifier comprises:
a high surface area metal oxide comprising oxides of barium, calcium, iron, lithium, manganese, molybdenum, nickel, potassium, rhenium, sodium, strontium, titanium, tungsten, and vanadium; and,
optionally, metallic nickel.
15 . The method as recited in claim 1 , wherein said nitrogen purifier comprises a nickel catalyst.
16 . The method as recited in claim 1 , wherein said hydrogen generator produces hydrogen from water by electrolytic means.
17 . The method as recited in claim 1 , wherein the concentration of an impurity in said quantity of purified hydrogen is reduced to less than 50 ppb.
18 . The method as recited in claim 1 , wherein the concentration of an impurity in said quantity of purified nitrogen is reduced to less than 50 ppb.
19 . The method as recited in claim 1 , wherein the concentration of an impurity in said quantity of purified hydrogen is reduced to less than 10 ppb.
20 . The method as recited in claim 1 , wherein the concentration of an impurity in said quantity of purified nitrogen is reduced to less than 10 ppb.
21 . A method for producing point of use ammonia gas from liquid water and nitrogen, comprising the steps of:
de-gassing a quantity of de-ionized water, to remove a portion of dissolved gasses in said quantity of de-ionized water;
feeding a quantity of said de-ionized, de-gassed water to a hydrogen generator;
producing a quantity of hydrogen from the quantity of said de-ionized, de-gassed water utilizing said hydrogen generator;
producing a quantity of purified hydrogen by passing said quantity of hydrogen through a hydrogen purifier;
producing a quantity of purified nitrogen by passing a quantity of nitrogen through a nitrogen purifier;
compressing said quantity of purified hydrogen and said quantity of purified nitrogen;
contacting said compressed quantity of purified hydrogen and said compressed quantity of purified nitrogen with a catalyst bed, wherein a portion of said purified hydrogen and a portion of said purified nitrogen react to form a quantity of ammonia;
producing a quantity of purified ammonia by passing said quantity of ammonia through an ammonia purifier; and,
delivering a portion of said quantity of purified ammonia to a semiconductor process tool.