## 1 Introduction  
Leguminous crops are an important source of protein and other essential nutrients in many diets around the world. In Morocco, leguminous crops are widely cultivated and play a key role in the country's agriculture and food security [1]. One of the most important leguminous crops in Morocco is lentils, which are grown in many regions throughout the country. However, once harvested, lentils and other leguminous crops are susceptible to damage from insects and other pests. In order to protect these crops during storage, farmers and other agricultural professionals often use insecticides and other control measures to prevent infestations and preserve the quality of the crops [2, 3]. Some of the most commonly used insecticides for leguminous crops in Morocco include pyrethroids, organophosphates, and neonicotinoids. While insecticides can be effective at controlling pests in stored leguminous crops, they also have some drawbacks. For example, some insecticides may be harmful to humans and other animals if ingested or inhaled [4, 5, 6, 7]. Additionally, some insects may develop resistance to certain types of insecticides over time, which can reduce their effectiveness. As a result, some farmers and other agricultural professionals in Morocco have begun to explore alternative methods of controlling insect pests in stored leguminous crops. One promising approach is the use of essential oils as pesticides [8; 9; 10].  
Essential oils are highly concentrated liquids that are extracted from plants using a variety of methods. Some essential oils have been shown to have insecticideal properties, which makes them potentially useful for controlling pests in stored leguminous crops [11; 12; 13; 14]. For example, essential oils from plants such as peppermint, thyme, and clove have all been shown to have insecticidal properties [15]. Using essential oils as insecticides has several potential advantages over traditional insecticides. For one, many essential oils and other natural compounds from plants are safe for humans and other animals, which makes them a potentially attractive option for farmers and other agricultural professionals who are concerned about the potential health risks associated with traditional insecticides [16]. Additionally, insects may be less likely to develop resistance to essential oils than they are to traditional insecticides, which can help to ensure their effectiveness over time. However, there are also some potential drawbacks to using essential oils as insecticides. For one, essential oils can be expensive, which can make them less practical for some farmers and other agricultural professionals. Additionally, essential oils may not be as effective at controlling pests as traditional insecticides, particularly in cases where infestations are severe [17; 18; 19].  
This study aimed to investigate natural and sustainable methods for controlling insect infestations in stored leguminous crops. Specifically, this study focused on a natural insecticide formulation comprising _Pinus halepensis_ essential oil (EOPH) and phosphogypsum (PG). This work begins with a physicochemical characterization of the essential oil and phosphogypsum, followed by an examination of the desorption process of the previously absorbed essential oil in PG. This study analyzes the behavior of the essential oil and establishes correlations between specific physicochemical parameters and biological parameters by utilizing experimental and analytical models.