1. Agrochemicals

• Copper as a Micronutrient: Copper is vital for various enzymatic processes, photosynthesis, and chlorophyll synthesis. Copper deficiency can lead to poor root growth, leaf chlorosis (yellowing), and reduced yields. 
• Foliar Spray and Soil Amendment: Copper(II) nitrate is a convenient way to provide copper to plants, either through foliar application (spraying directly on leaves) or by incorporating it into the soil. 
• Fungicide: Copper-based fungicides, including those derived from copper nitrate, work by deactivating fungal enzyme systems and preventing spore germination. They are often used to control diseases like blights, rusts, and scabs.

2. Performance Chemicals

• Nitration Reactions: Copper nitrate, particularly in combination with acetic anhydride, can effectively introduce a nitro group (-NO2) into aromatic compounds, a process known as nitration. This reaction is particularly useful for adding the nitro group to the ortho position of an activating group on the aromatic ring. 
• Catalysis: Copper nitrate act as a catalyst in various reactions, including those involving C-H bond activation. It can promote reactions by providing an alternative reaction pathway with a lower activation energy. It's used in the synthesis of nitrile oxides and other organic compounds. 
• Precursor: Copper nitrate can be transformed into other useful copper compounds, such as those used in wood preservation and electroplating. It's also used in the synthesis of metal-organic frameworks (MOFs).

3. Paints, Coatings & Adhesives

• Color Stabilization: Copper nitrate can help maintain the intended color of paints and coatings. It can prevent fading or discoloration caused by exposure to light or other environmental factors. This is achieved by minimizing color changes in the coating, leading to a more stable and consistent appearance over time. 
• Catalyst and Metal Surface Treatment: Copper nitrate acts as a catalyst in various chemical reactions, potentially speeding up the curing process of adhesives or other coating components. 

4. Metal Treatment

• Metal Coloring: Copper nitrate is a key component in achieving specific colorations on different metals. For example, it can be used to create a blackened or antique appearance on copper surfaces. 
• Surface Treatment: It's employed to brighten aluminum and create a burnished effect on iron.

5. Water Treatment

• Copper Recovery: Copper nitrate solutions are often found in electroplating and powder metallurgy wastewater. Methods like precipitation-electrolysis and displacement-electrolysis are used to recover copper from these solutions. 
• Catalysis: Copper nitrate and copper-based nanoparticles are used as catalysts in various reactions relevant to water treatment, including the reduction of nitrates and other pollutants.

6. Pharmaceuticals

• Precursor: Copper(II) nitrate also known as cupric nitrate, is used in pharmaceuticals as a precursor for synthesizing certain drugs and as a catalyst in various chemical reactions. It is also a component in the preparation of catalysts used in pharmaceutical manufacturing processes.