Process to reduce the pre-reduction step for catalysts for nanocarbon synthesis
A process to eliminate or reduce the pre-reduction step for catalysts for nano-carbon synthesis by first, heating a metal oxide at 5° C./min to 350-500° C. for 70-90 minutes under 10-20% hydrogen; optionally holding the temperature for 10 to 60 minutes; then initiating carbonaceous feedstock flow.
1 . A method of preparing and utilizing a catalyst for nano-fiber synthesis, comprising the following steps:
a. heating a metal oxide to an initial temperature of between 400 and 500° C. in 10-20% hydrogen at a heating rate of 1-10° C./min to affect its reduction and holding for around 10-60 minutes;
b. increasing the temperature to between 550-700° C.; and
c. passing a mixture of CO/H2 over the catalyst to produce the nano-carbon fibers.
2 . The method in claim 1 , wherein the metal oxide comprises iron oxide.
3 . The method in claim 1 , wherein the metal oxide comprises a mixture of iron and copper oxides.
4 . The method in claim 3 , wherein the mixture of iron and copper oxides contains a 99:1 to 50:50 weight ratio of Fe to Cu.
5 . The method in claim 1 , wherein the metal oxides are selected from a group consisting of oxides of iron, copper, nickel, molybdenum and combinations thereof.
6 . The method in claim 1 , wherein the heating time in step (a) is less than 60 minutes.
7 . The method in claim 1 , wherein steps a and b are performed in less than two hours time.
8 . The method in claim 1 , wherein the mixture of CO/H2 is provided at 1:4 to 4:1 by volume.
9 . The method in claim 1 , wherein the mixture of CO/H2 is provided at 1:4 by volume.
10 . The method in claim 1 , wherein the carbon production rate equals or exceeds 2.5 Carbon/g catalyst/hr.
11 . The method in claim 1 , wherein the method comprises a continuous method for producing catalyst and carbon nano-fibers by reducing the pre-reduction time ofthe catalyst.
12 . The method in claim 1 , wherein the hydrogen is balanced by an inert gas.
13 . A method of producing and utilizing a catalyst for nano-fiber synthesis, comprising the following steps:
a. heating a metal oxide catalyst to an initial temperature of between 400 and 500° C. in 10% hydrogen at a heating rate of 5° C./min to affect its reduction and holding for less than 60 minutes;
b. increasing the temperature to at least 550 oc;
c. passing a mixture of CO/H2 over the catalyst to produce nano-carbon fibers.
14 . The method in claim 13 wherein the mixture of CO/H2 is provided at 1:4 by volume.
15 . The process in claim 13 , wherein carbonaceous feedstock flow to produce nano-fibers begins within one hour from when the metal oxide catalyst is brought to its initial temperature of between 400 and 500° C.
16 . A method of producing and utilizing a catalyst for nano-fiber synthesis, comprising the following steps:
a. heating a metal oxide catalyst to an initial temperature of between 400 and 500° C. in 10-20% hydrogen at a heating rate of 5° C./min to affect its reduction and holding for around 10-60 minutes;
b. increasing the temperature to at least 550° C. but no higher than 700° C.;
c. passing a mixture of CO/H2 over the catalyst to produce nano-carbon fibers.
17 . The method in claim 16 , wherein the method comprises a continuous method of producing the catalyst for nano-fiber synthesis.
18 . A method of preparing a catalyst for nano-fiber synthesis, comprising the following steps:
a. heating a metal oxide to an initial temperature of between 400 and 500° C. in 10-20% hydrogen at a heating rate of 1-10° C./min to affect its reduction and holding for around 10-60 minutes; and
b. increasing the temperature of the catalyst to between 550-700° C. for use as a catalyst in producing nano-fiber synthesis.
19 . A method of producing a catalyst for nano-fiber synthesis, comprising the following steps:
a. heating a metal oxide catalyst to an initial temperature of between 400 and 500° C. in 10% hydrogen at a heating rate of 5° C./min to affect its reduction and holding for less than 60 minutes; and
b. increasing the temperature of the catalyst to at least 550° C. for use in producing nano-carbon fibers.
20 . A method of producing a catalyst for nano-fiber synthesis, comprising the following steps:
a. heating a metal oxide catalyst to an initial temperature of between 400 and 500° C. in 10-20% hydrogen at a heating rate of 5° C./min to affect its reduction and holding for around 10-60 minutes; and
b. increasing the temperature of the catalyst to at least 550° C. but no higher than 700° C. so that the catalyst can be used to produce nano-carbon fibers.
21 . (canceled)
22 . The method of claim 18 , wherein a mixture of CO/H2 is passed over the catalyst to produce nano-carbon fibers.
23 . The method in claim 19 , wherein a mixture of CO/H2 is passed over the catalyst to produce nano-carbon fibers.
24 . The method of claim 20 , wherein a mixture of CO/H2 is passed over the catalyst to produce nano-carbon fibers.