CN1045193C

CN1045193C - Production technique of cobaltous oxide

Info

Publication number: CN1045193C
Application number: CN 96117017
Authority: CN
Inventors: 刘宝峰
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-07-11
Filing date: 1996-07-11
Publication date: 1999-09-22
Anticipated expiration: 2016-07-11
Also published as: CN1144773A

Abstract

The present invention relates to a cobaltous oxide production technology which orderly comprises the steps of acidolysis, purification and deferrization, dehydration, drying, calcination, etc. Cobaltous oxide produced by the technology is used as a catalyst of a rechargeable nickel-hydrogen battery. Compared with cobalt powder with the cobalt content of over 99 %, the present invention has the advantages of less raw material and production cost, good activity, strong catalytic power and increased nickelous hydroxide utilization ratio.

Description

The production technique of cobaltous oxide

The present invention relates to the production technique of cobaltous oxide, especially be used as the production technique of the cobaltous oxide of nickel metal hydride battery catalyzer.

At present, in the battery production, generally use the catalyzer of cobalt powder as the rechargeable type nickel metal hydride battery.Because the content higher (up to more than 99%) of cobalt in the cobalt powder, not only waste raw material, the production cost height, and because its poor activity causes the utilization ratio of nickel hydroxide very low.

The object of the present invention is to provide a kind of production technique of cobaltous oxide, with the cobaltous oxide that this technology is made, it is low, active good to contain the cobalt amount, and alternative cobalt powder is as the catalyzer of rechargeable type nickel metal hydride battery, can improve the utilization ratio of nickel hydroxide, reduce production costs greatly.

Technical solution of the present invention may further comprise the steps successively: earlier cobalt ingot (or cobalt button) is inserted in the reactive tank, add ionized water and nitric acid, and be heated to 50～100 ℃ slowly and make its reaction, acidolysis becomes cobalt nitrate solution; Afterwards, cobalt nitrate solution is pumped in the reactor, and be heated to 50～100 ℃, when evenly stirring, add neutralizing agent slowly, transfer its pH value to 3.5～5.4,, remove scum through press filtration.The cobalt nitrate solution that to remove scum again pumps in the reactor, and it is heated to 50～100 ℃, when evenly stirring, adds soda ash solution and makes the cobalt precipitation, obtains cobaltous carbonate.At last, through dehydration, oven dry, cobaltous oxide is made in roasting under 350～600 ℃ of temperature, in inert or the little reducing atmosphere.

The cobaltous oxide that adopts technology of the present invention to make, after tested, containing the cobalt amount only is 77～81.5%.As the catalyzer of rechargeable type nickel metal hydride battery, be that cobalt powder more than 99% is compared with containing the cobalt amount, not only economize in raw materials, also can reduce production costs greatly.On probation through Shenzhen BYD Industry Co., Ltd, can reduce cost more than 6%, and also active good, catalytic capability is strong, can make the utilization ratio of nickel hydroxide improve 2～4%.

Below by embodiment the present invention is described in further detail:

Earlier the cobalt ingot (or cobalt button) of 400kg is inserted in the reactive tank, add the ionized water of 500L and the nitric acid of 100L more successively, be heated to 90 ℃ slowly with steam, after treating its intense reaction, stop heating, allow it react voluntarily, become and contain the cobalt nitrate solution that the cobalt amount is 60～90g/L, pour out.Afterwards, cobalt nitrate solution is pumped in the reactor, and be heated to 90 ℃, when evenly stirring, add neutralizing agent slowly, make its pH value transfer to 4.5,, remove scum through press filtration.Neutralizing agent wherein is that concentration is 6% ammoniacal liquor.Again, add ionized water and dilute, make its cobalt contents reduce to 35～40g/L.Again the cobalt nitrate solution after the dilution is pumped in the reactor, and be heated to 83 ℃, when evenly stirring, add temperature slowly and be 60 ℃ soda ash solution, make its pH value transfer to 8.0, obtain cobaltous carbonate.At last, use centrifuge dewatering successively, be 100 ℃ baking oven baking and pulverizer pulverizing with temperature, and on two-tube reduction furnace, carry out roasting, make cobaltous oxide of the present invention under inert or the little reducing atmosphere, at 350～600 ℃.Wherein said inert or little reducing atmosphere are meant nitrogen or carbon monoxide, carbonic acid gas.

The concentration of the soda ash solution in the foregoing description is 10%.

Claims

1, the production technique of cobaltous oxide is characterized in that may further comprise the steps successively:

Earlier cobalt is inserted in the reactive tank, the ratio that adds 125l ionized water and 25l nitric acid in every 100kg cobalt adds ionized water and nitric acid, and it is heated to 90 ℃, after treating its intense reaction, stop heating, it is reacted voluntarily, and acidolysis becomes to contain the cobalt nitrate solution that the cobalt amount is 60～90g/l, and wherein: the concentration of nitric acid is 98%;

Afterwards, cobalt liquor is pumped in the reactor, and be heated to 50～100 ℃, when evenly stirring, add neutralizing agent slowly, transfer its pH value to 3.5～5.4, remove scum through press filtration; Neutralizing agent wherein is that concentration is 6% ammoniacal liquor;

The cobalt nitrate solution that to remove scum again pumps in the reactor, and it is heated to 50～100 ℃, when evenly stirring, by cobalt nitrate solution: the equivalent ratio adding soda ash solution of soda ash solution=1: 1, cobalt is precipitated fully, obtain cobaltous carbonate;

At last, through dehydration, oven dry, again under 350～600 ℃ of temperature, roasting 30～60 minutes in inert atmosphere or the little reducing atmosphere, make cobaltous oxide.

2, production technique according to claim 1, the concentration that it is characterized in that said soda ash solution is 10%.