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Keywords:

  • hydropyrolysis;
  • pyrolysis;
  • catalysis;
  • biomass;
  • gasoline;
  • diesel;
  • fuel

Abstract

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. EXPERIMENTAL
  5. EXPERIMENTAL RESULTS
  6. CONCLUSIONS
  7. Acknowledgements
  8. LITERATURE CITED

Cellulosic biomass can be directly converted to hydrocarbon transportation fuels through the use of hydropyrolysis or integrated hydropyrolysis plus hydroconversion (IH2). Hydropyrolysis performed in a fast fluidized bed under 14–35 bar of hydrogen pressure with an effective deoxygenation catalyst directly produces a fungible hydrocarbon product with less than 1 total acid number which can either be directly fed to a refinery or polished in an integrated hydroconversion reactor to produce gasoline and diesel with less than 1% oxygen. Experimental data from a 0.45 kg/h semi-continuous IH2 pilot plant is presented. Economics and life cycle analysis data will be presented later in this series, and will show that by employing IH2 technology, biomass can be converted to gasoline and diesel fuels at delivered costs of less and in some cases significantly less than $1.80/gallon with greater than 90% reduction in greenhouse gas emissions. Larger (2.08 kg/h) long-term continuous pilot-scale testing of the IH2 process will commence in the near future. As a biomass-to-fuels conversion technology, IH2 has the potential to substantially reduce US dependence on foreign oil, thereby reducing the price of transportation fuels and significantly lowering worldwide greenhouse gas emissions. © American Institute of Chemical Engineers Environ Prog, 2011


INTRODUCTION

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. EXPERIMENTAL
  5. EXPERIMENTAL RESULTS
  6. CONCLUSIONS
  7. Acknowledgements
  8. LITERATURE CITED

In the recent US Billion-Ton Update, the Department of Energy (DOE) has estimated that by 2022, up to 1.009 billion tons per year of lignocellulosic biomass would be available for conversion in the United States [1–4]. If all of that biomass were converted into liquid hydrocarbon fuels at a rate of 28% by mass, a large portion of imported crude used to make transportation fuels could be eliminated, as shown in Figure 1.

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Figure 1. Comparison of US transportation fuel [2, 3] to the potential for fuel production from US lignocellulosic biomass and vegetable oil [4]—volume basis.

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Fast pyrolysis has long been studied and proposed as a method for densifying lignocellulosic biomass to liquids which could then be burned to make electricity or be transported to oil refineries for processing into fungible fuels [5–7]. However, the oil produced from the fast pyrolysis of biomass possesses many undesirable properties, including a high total acid number (TAN ∼ 100–200), low heating value (∼ 11,809 kcal/kg), high oxygen content (∼ 40%), chemical instability, high water content (20%), and inherent incompatibility with petroleum fractions. Relative to liquid hydrocarbons, the low energy density of pyrolysis oil makes it expensive to transport and the high TAN of this liquid renders it metallurgically incompatible with conventional transport vessels and refinery hydroconversion equipment, both designed for feeds with TAN less than 2. Finally, metallurgical considerations aside, because pyrolysis oil is not miscible with petroleum fractions, if it is introduced into existing refinery equipment (i.e., hydrotreaters or hydrocrackers) a separate feed system will be required.

The fundamental problem with utilizing fast pyrolysis as a technological avenue for the conversion of biomass to fuels is that the liquid products of fast pyrolysis have little market demand and are difficult and expensive to upgrade to transportation fuels. In particular, upgrading pyrolysis oil through hydroconversion has been demonstrated in pilot testing but is carried out at low space velocities (0.1–0.2 LHSV), high pressures (1500–2500 psig), and short run times [8–10]. Pyrolysis oils upgraded to remove oxygen and make gasoline and diesel typically require an additional 3–5 wt % hydrogen, on a pyrolysis oil feed basis. When pyrolysis oil is upgraded to remove oxygen, the finished hydrocarbon yield is 26–30% of the starting biomass [10]. Special metallurgy is required for pyrolysis oil upgrading and ebullated beds may also be required to achieve sufficiently long run times and avoid reactor plugging issues associated with polymerization.

A better approach for biomass conversion is to develop a direct route for producing hydrocarbon gasoline and diesel fuels or blending components, which offer inherent infrastructure compatibility, have an established large market, and can be easily transported. This is achieved by using catalytic hydropyrolysis or integrated hydropyrolysis and hydroconversion (IH2). In catalytic hydropyrolysis, biomass is converted in a fluidized bed of catalyst under hydrogen pressure of 20–35 bar and temperatures of 350–480°C. Catalytic hydropyrolysis removes oxygen as water and COX while minimizing the undesirable acid catalyzed polymerization, aromatization, and coking reactions which characterize standard fast pyrolysis. Furthermore, catalytic hydropyrolysis with an active catalyst is an exothermic process when oxygen is removed and hydrogen is added to the hydrocarbon structure. The exothermic nature of hydropyrolysis eliminates the need for recirculation of the solid heat carrier which is required for conventional endothermic pyrolysis. With catalytic hydropyrolysis, biomass can be directly converted to a hydrocarbon product which can be moved to a refinery for polishing or further polished on the spot in an integrated hydrotreating reactor to stabilize and upgrade the product.

A unique and distinctive feature of the Gas Technology Institute (GTI) IH2 process is that all of the process hydrogen required for carrying out hydropyrolysis is produced within the process by reforming light gases (C1–C3 hydrocarbons and CO). The IH2 integrated process is schematically shown in Figure 2. An initial economic analysis shows that the IH2 process reduces the costs of handling, transporting, and processing biomass and it has about the same capital cost requirements as pyrolysis alone, making it a very attractive approach for producing fungible transportation fuels.

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Figure 2. IH2 system schematic, showing overall process flow.

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The IH2 process differs significantly from earlier work in hydropyrolysis. Some early studies of hydropyrolysis of biomass were carried out at low hydrogen pressures or employed no catalysts, which demonstrated no significant effect compared to pyrolysis [11–14]. Other early work was carried out in slurry autoclave reactors at high pressures (105–180 bar) with slow heat up using Pd, red mud, NiMo, and CoMo catalyst and a recycled solvent [14, 15]. Later work was performed in a rapidly stirred autoclave with no added solvent but was still carried out at high pressures (>105 bar) with relatively slow heat up [16]. These early experiments produced hydrocarbon products with oxygen contents as low as 10% which showed the potential for this approach. More recent studies have employed a two-stage approach and again reported the production of hydrocarbon products with 10% oxygen at 100 bar with moderate heat up rates [17].

In the experimental results we report in this article that IH2 has been carried out under fast heat up conditions (>100 °C/s) in a fluidized bed with an active hydropyrolysis catalyst under moderate hydrogen pressures of 14–35 bar. This approach has resulted in good yields of gasoline and diesel products with oxygen content less than 2.7% from the hydropyrolysis step and overall oxygen content less than 1%.

EXPERIMENTAL

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. EXPERIMENTAL
  5. EXPERIMENTAL RESULTS
  6. CONCLUSIONS
  7. Acknowledgements
  8. LITERATURE CITED

In experiments designed to validate the IH2 approach for producing fungible liquid fuels, a bubbling fluidized bed of catalyst was used and the biomass was conveyed to the hydropyrolysis reactor in a continuous fashion. In this way, very rapid heating of the biomass occurs when it is mixed with the catalyst. Initial experiments with this pilot plant were typically carried out over 3 h with a 1 micron filter positioned within the reactor, so that only vapor was removed and the reactor filled up with char over time. Typical biomass feed rates were 5 g/min. Hydropyrolysis weight hourly space velocity (WHSV) was 0.5–2.0. At the end of each test, the system was depressurized, cooled, and disassembled, liquids were recovered, feed and product were weighed, and the material balance was determined. Water and hydrocarbon products were collected in the knockout pots and separated cleanly into two phases.

The initial IH2 proof of concept reactor system is shown in Figure 3. This system was configured so that experiments could be carried out with the second (hydroconversion) reactor by-passed in order to gather performance data on only the hydropyrolysis section. The goal of these experiments was to quantify the yields and product quality of hydrocarbon fuels produced from a variety of biomass feedstocks.

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Figure 3. IH2 initial proof of principle pilot plant.

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Later, modifications were made to the same pilot plant so that the char could be continuously removed from the reactor and directed overhead to an externally heated filter assembly where it was collected separately from the catalyst. This allowed semi-continuous testing to be performed where the reactor could be run all day, then shut down overnight, and be restarted in the morning with a fresh load of biomass in the feed hopper and with the same catalyst in the reactor. With this technology demonstration unit, continuous catalyst–char separation was demonstrated, which is essential to the practical use of the technology. This pilot plant also allowed multi-day testing to be performed to demonstrate catalyst stability over 3-day test periods. The improved IH2 pilot plant with continuous char removal is shown in Figure 4.

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Figure 4. Improved IH2 pilot plant with continuous char removal.

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In order to achieve continuous separation of biomass and catalyst in catalytic hydropyrolysis, we have determined that the biomass fuel should be sized to be physically smaller and less dense than the catalyst. The mechanism we employed to effect efficient catalyst–char separation in the hydropyrolysis reactor first is shown in Figure 5.

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Figure 5. Mechanism of char–catalyst separation.

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Feedstocks

A number of feedstocks were tested in the IH2 system. An analysis of each feedstock is shown in Table 1.

Table 1. Biomass feedstock analyses.
ComponentWood (mixed)MapleLemna derivedAquaflow microalgaeBagasseMacroalgaeCorn stover
Feed %C (MF)49.750.246.343.143.134.040.2
Feed %H (MF)5.86.25.86.15.04.435.0
Feed %O (MF)43.942.835.720.435.323.635.7
Feed %N (MF)0.110.173.76.50.344.61.0
Feed %S (MF)0.030.020.30.70.101.90.05
Feed % ash (MF)0.50.68.223.116.229.418.1
Feed % moisture5.65.57.25.93.45.96.5
Feed H/C (MF)1.401.461.501.701.391.561.49

The wood feed was a mixed feed of 68% hardwood and 32% softwood, which represents a low-cost blend of available wood feeds in the upper Midwest of the United States. This mixed wood feed was provided by Johnson Timber. The lemna was obtained from Petroalgae and had been processed to extract much of the protein from the structure. Extracted lemna protein is sold as animal feed while the remaining solid lemna (called Lemna Derived) was used as feed for the IH2 process. The microalgae were wastewater algae with low lipid content obtained from Aquaflow. Bagasse and corn stover were obtained from Cargill and the bagasse had to be pelletized to be successfully fed to the hydropyrolysis unit. The macroalgae were natural ocean seaweed harvested from the ocean by Blue Marble algae. All of the microalgae and macroalgae used in these studies were naturally occurring species.

Biomass particle sizes of less than 1000 microns were used in these experiments to insure good fluidization of the biomass at the gas flow rate available. For the long maple tests, where char is continuously removed from catalyst, maple smaller than 212 microns was used with catalyst sized from 300 to 500 microns, to insure that char would be carried over to the filter and the catalyst would be retained in the bed. In commercial units, it is expected that biomass particle sizes of 2500 microns will be used in IH2, as is typical for fast pyrolysis.

Catalysts

All the catalysts used in these tests are specialty catalysts supplied by project partner CRI. In addition, one test was conducted with alumina in the first stage to quantify the effects of an inert heat carrier instead of a catalyst in the hydropyrolysis reactor. The catalyst was reduced in size to form a fully fluidized bed in the first-stage hydropyrolysis reactor. In the early tests, when an internal filter was used and catalyst and char were retained in the bed, the catalyst was 100–300 microns. In the later tests, where catalyst was retained in the bed and char was carried overhead, the catalyst size was from 300 to 500 microns.

EXPERIMENTAL RESULTS

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. EXPERIMENTAL
  5. EXPERIMENTAL RESULTS
  6. CONCLUSIONS
  7. Acknowledgements
  8. LITERATURE CITED

More than 40 hydropyrolysis experiments have been completed. Typical processing conditions and experimental results for a variety of feedstocks are presented in Tables 2 and 3. In these tables, the weight recovery relative to the weight of biomass fed is greater than 100% because it includes the hydrogen which is added to the structure during hydropyrolysis and hydroconversion. Hydrogen uptake was found to vary with experimental conditions and catalyst and ranged from 2 to 6%.

Table 2. Typical results of IH2 experiments with lemna and wood feedstocks.
Test1234
LemnaLemnaMixed woodMixed wood
Feed    
 Hydropyrolysis temperature (°C)343447389469
 Hydropyrolysis WHSV2.10.941.620.79
 Hydropyrolysis catalystCRI, S-211CRI, S-4211CRI, S-4211CRI, S-4211
 Hydroconversion temperature (°C)343371399371
 Hydroconversion WHSV1.180.520.450.44
 Hydroconversion catalystCRI, S-4202CRI, S-4202CRI, S-4202CRI, S-4202
 Time biomass fed (h)2.32.23.33.2
 Pressure (bar)19.522.422.422.4
Recovery and yield    
 Wt % recovery (relative to biomass)93.8104.3106.3106.6
 %C recovery9999.0101.0100.7
 Wt % C4+ liquid yield (MAF)27.229.525.826.4
 Wt % char yield (MAF)16.93.213.46.8
 Wt % water yield (MAF)35.541.337.034.7
 Wt % H2 added MAF (calc)3.55.64.65.7
 Wt % H2 available from reforming C1–C3 and CO3.45.24.55.8
Liquid analyses    
 Wt % oxygen<0.5<0.3< 2.20.7
 Wt % carbon85.5985.5885.2588.37
 Wt % hydrogen14.1014.1711.4512.96
 Wt % nitrogen0.0370.240.060.04
 Wt % sulfur0.0040.010.010.01
 Density (g/cc)0.750.740.860.78
 % Gasoline C4–174°C59736678
 % Diesel 174°C +41273422
 TAN (total acid number)0.30.30.330.23
 RON of condensed gasoline84858691
 H/C1.981.991.611.75
Water analysis    
 pH121089
 % carbon5.05.10.190.52
 % ammonia6.26.70.130.4
Table 3. Typical results of IH2 experiments with bagasse, corn stover, microalgae, and seaweed algae feedstocks.
Test56789
BagasseCorn stoverMicroalgaeSeaweed algaeSeaweed algae
Feed     
 Hydropyrolysis temperature (°C)387418403379336
 Hydropyrolysis WHSV1.221.061.902.381.87
 Hydropyrolysis catalystCRI, S-4211CRI, S-4211CRI, S-4211CRI, S-4211CRI, S-4211
 Hydroconversion temperature (°C)399399399399399
 Hydroconversion WHSV0.340.440.520.650.51
 Hydroconversion catalystCRI, S-4202CRI, S-4202CRI, S-4202CRI, S-4202CRI, S-4202
 Time biomass fed (h)2.253.02.71.92.3
 Pressure (bar)22.422.422.422.422.4
Recovery and yield     
 Wt % recovery (relative to biomass)106.7102.895.592.9101.2
 %C recovery10495.19688.4115.2
 Wt % C4+ liquid yield (MAF)28.620.646.336.126.9
 Wt % char yield (MAF)6.813.95.26.022.9
 Wt % water yield (MAF)33.339.732.242.431.5
 Wt % H2 added MAF (calculated)6.14.23.94.13.9
 Wt % H2 available from reforming C1–C3 and CO6.44.34.13.43.8
Liquid analysis     
 Wt % oxygen<0.50.30.30.540.62
 Wt % carbon85.6187.6285.37 86.11
 Wt % hydrogen13.5711.8713.58 13.13
 Wt % nitrogen0.030.140.760.280.09
 Wt % sulfur0.210.070.030.220.05
 Density (g/cc)0.810.820.790.780.82
 % gasoline C4–174°C7570535264
 % diesel 174°C +2530474836
 TAN (total acid number)0.70.670.30.320.95
 RON of condensed gasolinenm85.281.589.383.0
 H/C1.901.621.91 1.83
Water analysis     
 pH1010111210
 % carbon1.390.824.355.618.1
 % ammonia1.01.47.36.97.1

There was no increase in pressure drop across the 1 micron filter or signs of coking on the filtering surface in the hydropyrolysis pilot plant because the products of hydropyrolysis are stable hydrocarbons. In contrast, when barrier filters are employed in fast pyrolysis, over time they have been observed to exhibit a monotonically increasing residual pressure drop (after cleaning) and a tendency to rapidly develop deposits of coke, which directly reflects pyrolysis product reactivity and tendency to coke [18].

In hydropyrolysis, liquid products are condensed and the hydrocarbon phase floats cleanly on top of a separated water phase. A typical IH2 product is shown in Figure 6. This contrasts with the single phase mixture of pyrolysis oil and water produced from typical fast pyrolysis shown in Figure 7, which generally is collected via quench.

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Figure 6. IH2 liquid product from wood; Top phase hydrocarbon, bottom phase water.

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Figure 7. Pyrolysis oil—picture from Ensyn website [19].

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Because the original IH2 pilot plant was configured with a small pressurized feed hopper and internal char filter, tests were limited to 2–4 h because the bed filled up with char or the feed was exhausted, either of which terminated the experiment. The improved IH2 pilot plant was configured with an external, heated filter with an enlarged char reservoir and an improved pressurized feeding system. This permitted much longer tests to be carried out. In the set of experiments reported in Table 4 (Tests 10 and 11), the improved IH2 pilot plant was employed for an extended series of nominal 3-day, 6-h/day tests with testing ending in the late afternoon after which liquids and char were recovered, and on the following morning, testing was restarted with fresh feed and the same catalyst bed. Inspection of Table 4 reveals that the liquid product from the Test 10 18-h test and Test 11 20-h test contained less than 1% oxygen, indicating good catalyst stability over the longer periods of testing.

Table 4. Results of extended IH2 experiments with a maple feedstock.
Test1011
MapleMaple
Feed  
 Hydropyrolysis temperature (°C)429394
 Hydropyrolysis WHSV1.701.49
 Hydropyrolysis catalystCRI, S-4211CRI, S-4211
 Hydroconversion temperature (°C)640710
 Hydroconversion WHSV0.470.41
 Hydroconversion catalystCRI, S-4202CRI, S-4202
 Time biomass fed (h)18.420
 Pressure (bar)22.424.1
Recovery and yield  
 Wt % recovery (relative to biomass)103.9108
 %C recovery98.6104.7
 Wt % C4+ liquid yield (MAF)27.926.1
 Wt % char yield (MAF)8.79.3
 Wt % water yield (MAF)36.136.3
 Wt % H2 added MAF (calc)4.65.9
 Wt % H2 available from reforming C1–C3 and CO4.85.7
Liquid analysis—3 day composite  
 Wt % oxygen<1.0<0.5
 Wt % carbon87.4388.82
 Wt % hydrogen10.8611.18
 Wt % nitrogen0.010.01
 Wt % sulfur0.010.06
 Density (g/cc)0.800.79
 % gasoline C4–174°C7768
 % diesel 174°C +2332
 TAN (total acid number)0.600.43
 RON(research octane number)—calculated from PIANO of condensed gasoline8887
 H/C1.481.51
Water analysis  
 pH99
 Wt % carbon0.60.3
 Wt % ammoniana0.16
Char analysis  
 Wt % C78.4678.66
 Wt % ash11.79.4

In most cases, sufficient hydrogen can be produced by reforming CO and light C1–C3 hydrocarbon gas products to generate the hydrogen required for hydropyrolysis and hydroconversion (i.e., maintain hydrogen balance), however, those cases that are not in hydrogen balance can be put in balance by increasing the reactor temperature to make more light ends and less char. This is because in the IH2 process, C1–C3 hydrocarbon gas yields increase as hydropyrolysis temperature increases, as shown in Figure 8 and char yields decrease as hydropyrolysis temperature increases, as shown in Figure 9.

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Figure 8. Weight% C1–C3 hydrocarbons versus hydropyrolysis temperature for the IH2 process.

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Figure 9. Weight% char versus hydropyrolysis temperature for the IH2 process.

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The experimental results presented in Table 5 (Tests 12–15) were carried out with the first-stage hydropyrolysis reactor in place but with the second-stage hydrotreater bypassed. With an active catalyst such as CRI, S-4211 or CRI, S-4201 at an elevated temperature, Tests 12 and 13 show that most of the biomass oxygen is removed in the first stage (i.e., in hydropyrolysis). However, when CRI, S-4201 is employed at a relatively low temperature (Test 14) or just a base, non-catalytic alumina is employed, as in Test 15, low oxygen removals result, with high yields of char, and decreased liquid products yield. These tests clearly demonstrate that catalyst choice significantly affects every figure of merit for the IH2 process. Thus, with an appropriately active catalyst, most of the oxygen removal is carried out in the first-stage hydropyrolysis reactor, while the second-stage hydrotreater acts primarily as a catalytic polishing reactor.

Table 5. Results of IH2 experiments with a mixed wood feedstock and no hydroconversion stage demonstrating the effectiveness of the first stage catalyst.
Test12131415
Mixed woodMixed woodMixed woodMixed wood
Feed    
 Hydropyrolysis temperature (°C)453396392391
 Hydropyrolysis WHSV0.621.522.42.1
 Hydropyrolysis catalystCRI, S-4201CRI, S-4211CRI, S-4201Alumina
 Hydroconversion temperature (°C)
 Hydroconversion WHSV
 Hydroconversion catalystNoneNoneNoneNone
 Time biomass fed (h)3.93.42.12.0
 Pressure (bar)22.422.422.422.4
Recovery and yield    
 Wt % recovery (relative to biomass)107.7104.896.687.3
 %C recovery98.8104.093.882.1
 Wt % C4+ liquid yield (MAF)24.125.124.614.4
 Wt % char yield (MAF)12.714.019.427.3
 Wt % water yield (MAF)32.434.129.930.6
 Wt % H2 added MAF (calc)3.74.61.40.1
 Wt % H2 available from reforming C1–C3 and CO4.35.02.72.0
Liquid analysis    
 Wt % oxygen2.60.487.7414.34
 Wt % carbon86.9787.2282.2977.42
 Wt % hydrogen11.3711.979.5911.70
 Wt % nitrogen0.10.040.070.05
 Wt % sulfur0.03nana0.04
 Density (g/cc)0.850.820.951.02
 % gasoline C4–345°F68643524
 % diesel 345°F +32366576
 TAN (total acid number)0.350.500.5Na
 RON of condensed gasoline89878987
 H/C1.561.651.401.81
Water analysis    
 pH9984
 % Carbon1.080290422.4
 % Ammonia0.20.20.040.04

The graphs in Figure 10 show boiling point distributions measured for the hydrocarbon liquids recovered in Tests 12 and 13. These data reveal that the liquids produced in the first stage of the IH2 process possess a smooth boiling distribution, primarily in the gasoline, jet, and diesel range.

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Figure 10. Boiling point distribution of liquids (based on simulated GC simulated distillation) produced in the first stage of the IH2 process.

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Because of the reactive nature of pyrolysis oil, boiling point information is not available for this material because it tends to decompose and carbonize (coke) during distillation. However, it is possible to compare the average molecular weight of pyrolysis oil with that of the liquids obtained from catalytic hydropyrolysis. Figure 11 provides such a comparison and reveals that pyrolysis oil has a much higher molecular weight than hydropyrolysis oil. Fresh pyrolysis oil has been found to have an average molecular weight of 530 and aged pyrolysis oil has been found to have an average molecular weight of up to 740, using gel permeation chromatography (GPC) when stored at 37°C [20]. We have determined that hydropyrolysis oil from the first stage of the IH2 process has an average molecular weight ranging from 158 to 215, (calculated from the hydrocarbon analysis) depending on the catalyst and conditions employed.

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Figure 11. Comparison of the average molecular weights of pyrolysis oil and hydropyrolysis oil from the first stage of the IH2 process (wood feed).

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One of the important aspects of the IH2 process is that it effectively processes a variety of feedstocks, including wood, corn stover, lemna, and algae. However, different feedstocks produce different average liquid yields and a rough correlation has been developed between liquid yield and the H/C ratio of the parent biomass. This relationship is shown in Figure 12. In this figure, algae possess a high H/C ratio and a concomitantly high liquid yield. Wood is characterized by a lower H/C ratio and lower liquid yields.

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Figure 12. Effect of H/C ratio on liquid yield for feedstocks tested in the development and validation of the IH2 process.

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CONCLUSIONS

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. EXPERIMENTAL
  5. EXPERIMENTAL RESULTS
  6. CONCLUSIONS
  7. Acknowledgements
  8. LITERATURE CITED

The Gas Technology Institute has developed a new catalytic technology for thermochemically converting biomass directly into gasoline and diesel fuels. This novel thermochemical technology produces hydrocarbon gasoline and diesel fuels and blendstocks directly from biomass. Initial pilot plant testing has demonstrated and validated the conceptual and technical basis of this process for which a number of domestic and international patent applications have been filed. Part 1 of this series presents and reviews selected results of initial pilot plant tests of the IH2 process that clearly demonstrate the opportunity provided by this new technology. In later parts of this series, we will present technoeconomic and life cycle analyses of the IH2 process and justify our assertion that through this process, biomass can be converted to gasoline and diesel fuels at a delivered cost of less than $1.80/gallon with greater than 90% reduction in greenhouse gas emissions.

Clearly, additional development work is required to rigorously test, demonstrate, and commercialize the process and verify catalyst life. To continue and expand this effort, a 50 kg/day, continuous IH2 pilot plant is nearing delivery which is scheduled to commence a preplanned series of long-term tests in the fall of 2011. This unique facility will be used to develop the detailed design and performance data required to commercialize the IH2 technology.

Acknowledgements

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. EXPERIMENTAL
  5. EXPERIMENTAL RESULTS
  6. CONCLUSIONS
  7. Acknowledgements
  8. LITERATURE CITED

GTI would like to acknowledge the help of CRI Catalyst Company in providing the catalysts used in these studies. CRI is the exclusive global licensor for the IH2 process and the sole provider of catalyst used in the process. GTI would like to acknowledge the work of Professor Shonnard of MTU in performing the preliminary life cycle analysis of the IH2 process. GTI would also like to acknowledge funding of the research through DOE Cooperative Agreement DE-EE0002873.

LITERATURE CITED

  1. Top of page
  2. Abstract
  3. INTRODUCTION
  4. EXPERIMENTAL
  5. EXPERIMENTAL RESULTS
  6. CONCLUSIONS
  7. Acknowledgements
  8. LITERATURE CITED
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  • 2
    Fuel Consumption by Mode of Transportation in Physical Units. ( 2009). http://www.bts.gov/publications/ national_transportation_statistics/html/table_04_05.html. Accessed on 12/9/2011.
  • 3
    Motor Vehicle Fuel Consumption and Travel. ( 2009). http:// www.bts.gov/publications/national_transportation_statistics/html/table_04_09.html. Accessed on 12/9/2011.
  • 4
    USDA Oil Crops Yearbook. (2009–2010). http://usda.mannlib.cornell.edu/MannUsda/viewDocumentInfo.do?documentID=1290. Accessed on 12/9/2011
  • 5
    Hulet, C.,Briens, C.,Berruti, F., &Chan, E.W.( 2005). A review of short residence time cracking processes. International Journal of Chemical Reactor Engineering, 3:R1 pp 74.
  • 6
    Bridgwater, A.V.,Meier, D., &Radlein, D.( 1999). An overview of fast pyrolysis of biomass. Organic Geochemistry, 30, 14791493.
  • 7
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