The most efficient and cost-effective process for producing ammonium nitrate fertilizer on a large scale is the Haber-Bosch process, which involves the synthesis of ammonia NH3 from nitrogen N2 and hydrogen H2 gases, followed by the Ostwald process to convert ammonia into nitric acid HNO3 , and finally, the neutralization of nitric acid with ammonia to produce ammonium nitrate NH4NO3 .1. Haber-Bosch process: Nitrogen and hydrogen gases are combined under high pressure 150-300 atm and temperature 400-500C in the presence of an iron-based catalyst to produce ammonia. This process is energy-intensive but has been optimized over the years to improve efficiency.2. Ostwald process: Ammonia is oxidized in the presence of a platinum-rhodium catalyst at high temperature about 900C and atmospheric pressure to produce nitric oxide NO , which is then further oxidized to nitrogen dioxide NO2 . The nitrogen dioxide is absorbed in water to form nitric acid HNO3 .3. Neutralization: Nitric acid is then combined with ammonia in a neutralization reactor to produce ammonium nitrate NH4NO3 .To minimize the environmental impact and ensure safety measures, the following steps can be taken:1. Use renewable energy sources or energy-efficient technologies to power the Haber-Bosch process, reducing greenhouse gas emissions.2. Implement proper waste management and recycling systems to minimize the release of harmful by-products and pollutants.3. Employ advanced monitoring and control systems to ensure safe operation and prevent accidental releases of hazardous materials.4. Store and handle ammonium nitrate with care, as it can be an explosive hazard under certain conditions. This includes proper storage facilities, temperature control, and avoiding contact with incompatible materials.5. Regularly assess and update safety measures, following industry best practices and regulatory guidelines.