# Cleaner Processes for Making Laundry Soap from Vegetable Oils and an Essential Oil
## 1 Introduction
Their presence in wastewater will make the purification process more difficult. In addition, avoiding other synthetic chemicals in soap manufacturing is necessary to maintain the syntagma of _natural soap_, i.e., formulated only with ingredients from nature. The success of natural soaps depends on factors such as raw material quality, final product quality, marketing strategy, and customer satisfaction. Comparing the life cycles of soaps with those of detergents, it is found that natural soaps have a lower impact on the environment in each of the five stages, as follows:  
* _In the case of natural soaps_: (1) raw materials: renewable plant-based oils, biodegradable ingredients; (2) production: simpler, low energy consumption, minimal waste generation; (3) packaging: paper, cardboard, and therefore biodegradable packaging; (4) use:biodegradable product, minimal environmental impact, low water consumption; (5) end of life: biodegradable, minimal waste if the packaging is ecological [22]. * _In the case of detergents_: (1) raw materials: non-renewable chemicals, petroleum-based, high carbon footprint; (2) production: more complex, energy-consuming, generates chemical waste; (3) packaging: non-ecological packaging, in plastic bags that lead to significant waste generation; (4) use: pollute water, contain non-biodegradable compounds, high water consumption; (5) end of life: plastic waste, non-biodegradable chemicals persist in water systems [23; 24; 25; 26; 27; 28; 29]. The raw materials used to obtain a natural soap refer to triglycerides in the form of vegetable oils or animal fats that contain saturated and unsaturated fatty acids, with long alkyl chains and which, during the saponification process, are transformed into soaps [30]. Although both saponification variants use the same ingredients (triglycerides and alkali), there are differences in temperature and time during the saponification process. In the presence of a strong alkali, the reaction can easily take place hot (1 h), or cold (after a minimum of 1 month of ripening). When saponification is carried out hot, there is a single stage of making the soap, which can be used immediately after the cooling stage. The cold saponification process takes place in two stages: the first stage consists of starting the cold saponification by mixing the oils, fats with NaOH, and, in the second stage, ripening takes place, that is, the slow development of the saponification reaction, for 1 month when exposed to a well-ventilated and moisture-free environment [31; 32]. These storage conditions are necessary to prevent any moisture build-up that could affect the soap; it is established that, during the maturation stage, soap undergoes a slow evaporation process, in which excess water is removed, thus allowing the soap to harden properly. It is also necessary to regularly monitor environmental conditions, such as temperature, humidity and exposure to light, as fluctuations in these conditions can negatively affect the quality of the soap, leading to problems such as melting, discoloration or the development of rancidity [33; 34; 35; 36; 37; 38]. The two types of saponification processes lead to the formation of glycerin and a mixture of fatty acid salts. These carboxylate salts are actually mixtures of soaps [39; 40]. When soap is formulated at home, the final product has better qualities for both human skin and washed laundry. If glycerin formed as a by-product of the reaction is not removed for use in other areas, it functions as an embilient for hand skin and as a good antistatic/softening agent for laundry washed with such soaps [39; 41]. Soaps, like laundry detergents, have a high cleaning capacity because they contain two parts: a polar part (carboxylic group), with an affinity for water, and a nonpolar part (hydrocarbon chain) with an affinity for greasy dirt [42]. Another component that can be added at the end of saponification to give natural soap a fragrant scent is actually an essential oil.