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The aim of this study was to explore the potential of crude xylano-pectinolytic enzymes in bio-pulping of rice straw, in order to reduce environmental pollution. In this study, the effect of integration of bio-pulping strategy before chemical pulping of rice straw has been investigated. The bio-pulping efficiency was found to be maximum at xylanase:pectinase dose of 400:120 IU/g rice straw, temperature 55 °C, treatment time 3 h, Tween 80 (1%), pH 8.5 and pulping consistency 1:10 (g/mL). Bio-pulping enhanced the permeability of pulping chemicals, generated pulp with higher yield, brightness, along with higher residual active alkali content of black liquor in comparison to the pulp obtained after chemical pulping. Bio-pulping also resulted in 10% reduction of alkali dose and improved paper quality, with increase in breaking length (13.9%), burst index (27.0%), double fold (39.3%), gurley porosity (18.75%) and viscosity (8.77%) of unbleached bio-pulp. Bio-pulping also improved the bleachability by removing the D2 step of bleaching and produced pulp with higher physical strength properties, breaking length (15.92%), burst index (20.47%), tear index (3.87%), double fold (36.0%), gurley porosity (25.0%) and viscosity (28.36%). Hence, this environmentally sustainable bio-pulping approach can decrease the chemical load and ultimately pollution, along with enhance the yield and quality of paper. This is the first report demonstrating cleaner pulping of rice straw using crude xylano-pectinolytic enzymes, produced by a bacterial isolate.

IntroductionHospitals in the Netherlands generate approximately 1.3 million kg of waste from the polypropylene (PP) wrapping paper (WP) used to wrap surgical instruments each year. The aim of this study was to develop a method to recycle WP waste into new medical devices.MethodsWP was recovered from Maasstad Hospital, Netherlands. The WP was melted into bars, granulated, and mixed with virgin material at different ratios and temperatures. Dog bones were injection-molded from volume (v.%) virgin, mixed (%R), and recycled (100%R) granulate, and a tensile testing machine was used to compare the material properties before and after ten disinfection cycles at the sterilization department. Then, 25 instrument openers were made from the 50%R material and circulated for four weeks.ResultsThe data indicated no significant differences in the mechanical properties at different melting temperatures. For dog bones made from the 100%R, 50%R, and virgin granulate, the Young's moduli were 1021 (SD13), 879 (SD13), and 795 (SD14) MPa, and the strains were 8%, 12%, and 14%. Ten disinfection cycles did not significantly change the material properties. After one month, the openers did not show any deterioration or damage other than surface scratches.DiscussionThe results indicated that the initial WP melting temperature did not influence the mechanical properties. Although devices could be produced directly from the recycled WP granulate, increasing the recycled granulate in the mix ratio increased the strength and brittleness.ConclusionsIt is feasible to recycle WP waste into a high-quality raw material for the injection molding of medical devices without using additives. This would allow hospitals to become more compliant with the circular economy enabling economically viable and circular processes that positively contribute to cleaner technical processes, sustainable products, and the reduction of medical waste.

Social life cycle assessment (S-LCA) is a tool to address social impacts from a life cycle perspective. This work presents the first S-LCA of the Portuguese pulp and paper sector. It presents the social risks and the positive social impacts of the sector, which have not been extensively covered in the scientific literature. Two different approaches were used to compile the social life cycle inventory based on input-output analysis. Approach 1 was based on impact analysis of changes in added value. Approach 2 was based on structural path analysis, supporting the disaggregation by production levels (or tiers). The functional unit was the production of 1 United States Dollar in the Portuguese pulp and paper sector. In the social life cycle impact assessment, the social risk assessment was conducted using the Social Hotspots Database. The positive impacts were addressed considering indicators of employment and remuneration, namely total employment, number of employees, labor compensation, and compensation of employees. Based on Approach 1, the results of the social risks showed the Portuguese pulp and paper industry, commerce and forestry sectors, and the Spanish forestry sector as the critical sectors. Based on Approach 2, Portugal and Spain continued to be the countries having the greatest social risks. Other contributions of countries were identified at different production levels, particularly China in tier 3. In both approaches, the stakeholder category ‘worker’ was the most critical. Regarding the positive social impacts, Approach 1 showed that Portugal and Spain contribute to the highest employment level linked to the pulp and paper, commerce, and forestry sectors. Approach 2 supported the differentiation of employment and remuneration at different production levels. Tier 2 (direct suppliers) presented the highest employment level and people engaged and the lowest remuneration level. The results showed that Approach 1 provides a faster and more aggregated assessment of social risks and positive social impacts. Furthermore, Approach 2 allowed a more detailed evaluation, providing a better understanding of the social risks and positive social impacts on the supply chain. Thus, Approach 2 is encouraged for different applications since it produces a better understanding of where social risks and positive social impacts occur, providing better guidance for corrective measures and decision-making.