Synthesis of Glues with Citric Acid and Sulfuric Acid Protonic Acid-H+ as Catalysts Using Banana Peel and Kaki as Valorised Raw Materials

Abstract

Seeing that banana peel or banana skin composed 35% to 40% of banana fruit and also seeing that kaki were widely cultivated at Madagascar since the XIXth century with non-negligible quantities of valorisable waste during their collection; a study of their valorization as raw materials to synthesize glues was undertaken in this manuscript. Synthesized glues were classified into two categories: the ecological glues with citric acid protonic acid H+ catalyst and the sulfuric acid glues-Sglues with sulfuric acid protonic acid H+ catalyst. All glues were composed with two main compounds firstly the pH-raiser-support and secondly the crushed banana peel citric acid esters EAcBa. These pH-raiser-supports was composed not only with citric acid protonic acid H+ catalyst (E-pH-Natural for the ecological glues) and/or sulfuric acid protonic acid H+ catalyst (E-pHS-sulfuric acid for the Sglues) but also pure ethanol and kaki composed with alkenes organic functional group from its betacarotenes molecules; they increased the pH of the glues and catalysts were dispersed and moved on. All synthesized glues were tested such as: the ecological glues were tested to glue the school notebook paper and the Sglues were tested to glue the packing carton paper. So, to study the effects of these gluing components, the effects of the test papers dry matter, the effects of tested papers nature-components, and the effects of the test papers porosities; the total weight diminution of the glue-reagents which indicated the formation of covalent links between glues and paper responsible of its best gluing results were followed with time. In terms, the activities of each glues’ initial protonic acid H+ were calculated and confirmed their roles as very active catalysts for dehydration reactions particularly the sulfuric acid protonic acid H+ catalysts, for addition reactions principally esterification, additions with alkenes-C= and etherification for all synthesized glues especially with the stronger-smallest sulfuric acid protonic acid H+ which were responsible of their capacities to stick with very good quality.