USO DI SILICE MESOPOROSA

La tecnologia applicata alla produzione di carta/cartone ad uso alimentare, attraverso il trattamento con silici modificate, rimuove gli oli minerali (la cui frazione aromatica è un potenziale cancerogeno) senza alterare il colore della carta

Use of mesoporous silica

The currently available technologies enable limitation of organic contaminants migration from paper-based packaging to foodstuff through application of plastic, aluminum or activated carbon layers on/inside paper/paperboard foils. In any case, these technologies require ad hoc paper production chains, whilist contaminants are not removed from packaging. The patented technology allows for adsorbing and removing toxic contaminants (MOSH) and potential carcinogenics (MOAH) from paper/paperboard without the need to modify production line and without altering the cellulose neutral color. The patent application claims the use of mesoporous silicas at high affinity for mineral oil. The silicas are thermally regenerable and reusable in numerous production cycle

Stabilization of\ua0mineral oil hydrocarbons in\ua0recycled paper pulp by\ua0organo-functionalized mesoporous silicas and\ua0evaluation of\ua0migration to\ua0food

The occurrence of mineral oil hydrocarbons (MOH) in cellulose-based packaging is mainly due to the offset printing process where MOH are used as a ink pigments' solvent. The MOH migration from paper/paperboard to food is matter of concern for EFSA, members state authorities, consumers, and food industry. In this study, the feasibility to stabilize MOH by adding a sorbent into recycled paper obtained through a common washing process was investigated and the migration to wheat flour/Tenax\uc2\uae assessed. Among several white/pale yellow porous materials, organo-modified powder silica MCM-41-Si(CH3)3 showed the best combination between affinity for MOH (184% dw) and stability to thermal regeneration. A freshly issued newspaper with >3000\ua0mg\ua0MOH\ua0kg-1 was used to produce recycled paper at a laboratory-scale plant. MCM-41-Si(CH3)3 was added at the pulping step (1% dw) and the sorbent-enriched pulp handled according to a washing paper production process with no effect on the paper optical brightness. The MOH content of the wheat flour in contact with the sorbent-enriched paper under accelerated migration conditions (15\uc2\ua0days at 40 \uc2\ub0C) resulted 20% of that contacted with control paper (4.3 \ub1 1.1 and 20.4 \ub1 5.5\ua0mg\ua0kg-1, respectively), despite its contamination was 24% higher than the control. On the contrary, Tenax\uae contamination resulted 56.0 \ub1 10.0 and 47 \ub1 14.0\ua0mg\ua0kg-1 when exposed to sorbent-enriched and control paper, respectively