Developing fiber and mineral based composite materials from paper manufacturing by-products

Developing valuable materials from the by-products of paper industry can help to address some environmental and economic issues associated with traditional synthetic composites. Particularly, the management of paper mill sludge (PMS) waste remains an economic and environmental challenge for the pulp and paper industry. 11 million tons of PMS is generated annually in Europe from the wastewater treatment (WWT) process of paper mills. PMS is mostly used in low value applications. However, PMS contains fibers and minerals with physio-chemical properties that exhibit a high potential to substitute some conventional materials in other industries. The research presented in this paper aims to explore new directions for further investigation on PMS material applications by reviewing the literature on PMS materials and subsequently characterizing sludge from 6 different mills. The study shows the technical feasibility, opportunities and technological readiness of fiber and mineral based composites obtained from PMS, such as; cementitious products, polymer reinforcement and fiberboards

Kraft lignin: a novel alternative to oil spill cleanup recycling industrial waste

Oil spills occur frequently due to negligence or through acts of vandalism or war. Marine oil spills damage marine, coastal, and ter¬restrial habitats, as well as impact coastal economies. In order to palliate such issues, researchers are working to develop cost ef¬fective and environmentally safe methods of adsorbing oil from oil spills. In this paper, a complex chemical compound found in the secondary cell walls of plants and ex¬tracted as a waste product of the pulping process known as kraft lignin was tested as an adsorbing material for oil spills. Lignin is light, and its high surface energy and wet¬tability allow it to interact with charged oil droplets. It was found that lignin can absorb 80% of the carbon introduced into water by oil spills within 12 hours of treatment. This study demonstrates a novel method for resolving oil spills using kraft lignin. After it is saturated with oil, lignin can be inciner¬ated, and its high calorific value can be used to produce energy from what would other¬wise be a waste product.Les fuites de pétrole sont produites fréquemment à cause de la négligence, des actes de vandalisme ou de la guerre. Les fuites de pétrole en mer en¬dommagent les écosystèmes maritimes, côtières et terrestres, et affectent les économies côtières. Pour atténuer de tels problèmes, les chercheurs tentent de développer des méthodes rentables et écologiques pour absorber le pétrole des fuites. Dans ce rapport, un composé chimique compli¬qué trouvé dans la paroi cellulaire secondaire des plantes et extrait comme produit résiduaire du processus de réduction en pâte, connu sous le nom de lignine ‘kraft’, a été testé comme matériel absorbant pour les fuites de pétrole. Les pro¬priétés de la lignine, y compris sa légèreté, son énergie de surface élevée et sa mouillabilité, la permettent d’interagir avec les gouttes de pétrole chargées. La lignine est capable d’absorber 80% du charbon introduit dans l’eau par les fuites de pétrole en 12 heures de traitement ou moins. Cette étude démontre une solution originalepour l’absorption du pétrole des fuites pétro-lières. Après avoir été saturée avec le pétrole, la lignine peut être incinérée, et sa valeur calori-fique élevée permet la production d’énergie à partir de ce qui aurait été autrement gaspillé

Supercritical carbon dioxide extraction of four medicinal mediterranean plants

With everyday advances in the field of pharmaceuticals, medicinal plants have high priority regarding the introduction of novel synthetic compounds by the usage of environmentally friendly extraction technologies. Herein, a supercritical CO2 extraction method was implemented in the analysis of four plants (chamomile, St. John’s wort, yarrow, and curry plant) after which the non-targeted analysis of the chemical composition, phenolic content, and antioxidant activity was evaluated. The extraction yield was the highest for the chamomile (5%), while moderate yields were obtained for the other three plants. The chemical composition analyzed by gas chromatographyhigh-resolution mass spectrometry (GC-HRMS) and liquid chromatography-high-resolution mass spectrometry (LC-HRMS) demonstrated extraction of diverse compounds including terpenes and terpenoids, fatty acids, flavonoids and coumarins, functionalized phytosterols, and polyphenols. Voltammetry of microfilm immobilized on a glassy carbon electrode using square-wave voltammetry (SWV) was applied in the analysis of extracts. It was found that antioxidant activity obtained by SWV correlates well to 1,1-diphenyl-2-picrylhidrazine (DPPH) radical assay (R2 = 0.818) and ferric reducing antioxidant power (FRAP) assay (R2 = 0.640), but not to the total phenolic content (R 2 = 0.092). Effective results were obtained in terms of activity showing the potential usage of supercritical CO2 extraction to acquire bioactive compounds of interest