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Global sales of ammonia in 2008 are estimated at $103.5 billion, with one half of that amount directly relating to energy cost. In fact, the energy used in ammonia production alone equals 2% of the total energy consumed globally.

Ammonia is commonly known as a household cleanser, but its main use is critically important to the world's food supply. Ammonia serves as a primary foundation or precursor in fertilizers. As the key ingredient in food production, it is the second largest synthetically produced chemical by volume in the world (sulfuric acid is number one). The United States uses about 18.5 million tons of ammonia annually from the global production of 136 million tons, and 90% of this is used in agriculture. As of 2004, the U.S has dropped to the fourth largest ammonia producer, and now imports nearly 50% of its requirements.

It can be argued that ammonia is the manmade substance most critical to the existence of human society. The expansion of population since 1900 has been made possible by fertilizer driven agriculture, and modern nitrogen fertilizer is based on ammonia. Plants require nitrogen to produce protein, and ammonia is the only viable source for large-scale nitrogen applications. It is estimated that nearly 50% of the world's protein need is produced with nitrogen fertilizers based on ammonia. Ammonia is also a building block for the synthesis of many pharmaceuticals and other industrial chemicals.

The ammonia we have today is made with a century old process first developed in Germany by Fritz Haber. The initial bench top system, put into operation in 1909, produced a half cup an hour. Four years later, BASF chemist Carl Bosch had worked out the particulars of volume production and a large-scale plant was built at Oppau, Germany. The resulting Haber-Bosch process requires only pure nitrogen, pure hydrogen, and a high pressure reactor with an iron catalyst in order to produce ammonia. The nitrogen is relatively free and supplied from the air we breathe, but hydrogen, no matter what method used to obtain it, involves the use of energy. The primary energy sources used for making hydrogen today are natural gas and coal.

Today, there are hundreds of plants that produce ammonia in more than 80 countries and roughly 85% or more of the ammonia produced globally is used for fertilizing agricultural crops. In 2008, global ammonia production was 136 million tons (~300 billion pounds), and the forecast for world nitrogen fertilizer market growth is 1.4% annually. Some of the top ammonia-producing companies include Yara (Norway), Dyno Nobel, Terra Industries & Koch Industries (USA), Agrium & Potash (Canada), K+S & BASF (Germany), and Mitsui & Mitsubishi Chemical (Japan).

The US began a large increase in the utilization of ammonia beginning in 2001 due to the increased planting of corn for alcohol fuel production; this lead to a commensurate rapid increase in the cost of ammonia. At the same time, the price varied greatly depending on local natural gas and coal prices. For example, the price has ranged from $330/ton to over $1,200/ton delivered in Colby, Kansas over the last eight years. There is an obvious need to apply improvements in energy consumption, efficiency, and yields to the traditional Haber-Bosch process and very large potential gains.


The reaction between gaseous nitrogen and hydrogen (N₂ + 3H₂ -> 2NH₃) is the dominant process used for ammonia synthesis. The common feedstock for the hydrogen used in ammonia production is natural gas, which is reformed with steam to create hydrogen. Ammonia synthesis is limited by the slow reaction rate of conventional iron catalysts, which leads to large amounts of energy wasted in high pressures and temperatures. In addition, these high energy requirements contribute to large amounts of carbon dioxide emissions. Globally, ammonia generation produces over 400 million tons of CO₂ emissions per year, accounting for 1.6% of the world's total CO₂ emissions annually.

The relatively low activity of existing commercial iron catalysts leads to a number of problems. The slow kinetics, or rates of reaction, restricts the yield. They also require higher pressure and temperature levels to properly spread the concentrations of species (and create equilibrium). As the commercial catalysts are only active over a narrow temperature range (380-500° C) and unable to approach more than 80% of equilibrium, the process requires the highest pressures feasible and is still inefficient. Even at pressures up to 30 MPa (4,350 psi), commercial catalysts convert only about 15% of the hydrogen gas to ammonia per pass; the unreacted hydrogen-nitrogen mixture is recycled so that most of the hydrogen is eventually consumed. Generation of those high pressures and temperatures, typically 3,000 psi and 400°C, during plant operation requires large energy and cost expenditures. Additionally, the high pressures and temperature require very heavily walled reactors, compressors, and piping, resulting in high capital costs.


The increased surface energy of QSI's highly catalytic and proprietary nano iron particles has been demonstrated to increase the kinetic rate of ammonia synthesis by hundreds of times compared to conventional iron catalysts at low pressures. Most critically, it does so at 100 psi, thereby allowing a commercially useful ammonia synthesis rate at low pressures and temperatures, resulting in simplified plant construction and significant energy savings.


The higher surface area of smaller particles would be expected to improve the process; however, test runs with commercial iron catalysts have shown that high surface area alone is not sufficient to produce a suitable catalyst at low pressures. Although promoted iron catalysis for ammonia synthesis is still not entirely understood, there is strong evidence about structure and possible functioning mechanisms. The high catalytic activity of QSI's nano iron catalyst significantly increases the rate of the slowest step for ammonia synthesis, the adsorption and dissociation of nitrogen on the catalyst surface. This is believed to be due to the constrained spherical morphology of the QSI nanoparticles with multiple crystalline steps and ledges and controlled oxide layer around the metal core. These advanced catalysts, approximately 24 to 40 nanometers in diameter, create iron atoms with low coordination numbers and very high surface energies. QSI's supported iron catalysts with a surface area of 25m²/g have demonstrated the production of one thousand times more ammonia than a commercial iron catalyst having an average surface area of 140m²/g (for the production of ammonia at 20 psi or 0.138 MPa). By use of supported nano scale iron catalysts, QSI has demonstrated the conversion of 22% of the hydrogen to ammonia in one pass through the reactor at 100 psi. The synthesis of ammonia is currently being optimized at temperatures below 400°C and pressures ranging from 250-1,000 psi using a packed bed catalyst system of QSI's supported nano iron particles.

The benefits of using QSI's low-pressure, low-temperature ammonia synthesis catalysts can be found in tens of millions of potential capital cost savings and process efficiency improvements. For example, as lower pressures are used in the process, there is greater flexibility in process compressor driver selection, which is the most maintenance intensive part of the industrial ammonia synthesis process. There are similar savings in other stages. Also, thinner-walled and lighter reactor vessels, piping, valves, and fittings can be employed safely and fabricated at a lower cost. Leveraging this more economical and environmentally friendly process, American ammonia plants could be restructured to operate more profitably, thus generating more jobs and promoting domestic food security.

QSI's advanced iron catalyst opens a world of possibilities for industrial ammonia synthesis optimization, while maintaining high ammonia conversion levels and safety standards at dramatically reduced costs and increased profit. Partnership and commercialization efforts are underway.