The history of the Casale Group is the history of Ammonia Casale, the success of which started during the pioneering years at the beginning of the last century when men sought, and found, a way to produce one of the most important synthetic chemicals on an industrial scale: ammonia.Thanks to the abundant availability of this commodity, mankind was granted practically unlimited access to fertilisers and hence also to food.  The contribution of synthetic ammonia in improving the quality of life of the world population is second only to that of agriculture itself.  The effort devoted to researching ammonia synthesis also paved the way for producing many of the industrial chemicals offered today.At the time Ammonia Casale was founded, synthetic ammonia was only being produced in Germany by Badische Anilin und Soda Fabrik (BASF), which was the first company to produce ammonia industrially using the Haber-Bosch process.

The synthesis of ammonia from elements not only solved a fundamental problem in sustaining food supply but also opened a new era for technical chemistry by providing the basis for the development of high-pressure technology.

At that early stage, because of the relatively low synthesis pressure, water scrubbing was used to capture the product ammonia as an aqueous solution. The Ammonia Casale process operated at considerably higher pressure than the Haber-Bosch process which made it commercially possible to obtain pure ammonia by direct condensation, just as it is done today.

Ammonia Casale also greatly simplified the reactor design, both prolonging catalyst life and making catalyst replacement easier.

By 1923 Ammonia Casale technology had been adopted in Italy, France, Japan, Switzerland, Spain and the USA, with more than 15 plants producing altogether about 80,000 tons of ammonia per year.  At that time the only competitor was BASF.A successful methanol synthesis process was also introduced soon after the foundation of Ammonia Casale, while facilities to produce both catalysts for ammonia and methanol production, as well as high-pressure equipment, were set up to satisfy the needs of these rapidly growing industries.

Expansion continued at a rapid pace and by 1927, the year of Luigi Casale's sudden death, the process had also been adopted in Belgium, England, Russia, and even in Germany, with an overall ammonia production of more than 320,000 tons per year.More than 200 ammonia plants based on Casale's first generation technology were built worldwide, and the methanol process developed by Ammonia Casale remained the dominant technology for over 45 years.

In the mid 1960s the concept of single-train, energy-integrated ammonia and methanol plants, launched by Casale’s competitors, constituted a real technical revolution, sustaining the continuously increasing demand and leading to a new generation of advanced processes.In the early 1980s the still fast-growing product demand and increases in energy prices were a great challenge for the industry: existing ammonia plants, many with downstream urea plants (another fertilizer that became more and more important), and methanol plants were far from optimal with respect to energy consumption and to the ratio of capital to capacity.

As building new plants was in many cases too expensive, modernizing old plants to lower their energy consumption and raise their capacity levels became a subject of urgent interest to engineers.

As it had already done in the past, Casale set new benchmarks, developing innovative technologies and concepts that could increase the efficiency and capacity of existing plants for very low investment.

Up to the 1980s, activities were mainly concentrated in the field of ammonia production technology, though some work was also done early on in the field of methanol production technology. From the 1980s onwards, Ammonia Casale invested significantly in technology development, and thanks to a team of highly skilled specialists with long experience not only in the ammonia field but also in the fields of urea, methanol and derivatives, the company resumed activity in the field of methanol production technology and started working on technologies for the production of urea and methanol derivatives (eg. formaldehyde, MTO, dimethyl ether) as well as of hydrogen by electrolysis.With the increase of activity in the ammonia field, the resumption of activity in the methanol field, and the logical diversification into urea and methanol derivatives, at the beginning of the 1990s Ammonia Casale reorganized itself into a group of four companies each dedicated to its own particular field of activity.The Casale Group has upgraded key equipment, such as synthesis reactors, in many plants. Synthesis gas production units, constituting the front-end of ammonia and methanol synthesis plants, and entire urea plants have also been greatly improved within the same framework of "plant modernization".Recently, the Casale Group has also resumed the activity of designing grass-roots plants, and it has built and is currently building both methanol and ammonia plants.