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In present communication, waste frying oil (WFO) has been used as a feedstock for biodiesel synthesis. WFO, procured from a local Indian restaurant possessed an acid value of 0.84 mg KOH/g, which is low enough for single step transesterification reaction. Biodiesel (fatty acid methyl esters) was washed after transesterification reaction and the yield got lowered substantially (from 96% to 86.36%) after water washing owing to loss of esters. 30:100 vol% (methanol to oil), 0.6 wt% NaOCH3, 60°C temperature and 600 rpm agitation in 1 h reaction time was found to be optimum for transesterification reaction. 1H NMR spectrum showed a high conversion (95.19%) of fatty acids in WFO to biodiesel in 2 h reaction time. Almost complete conversion (99.68%) was attained in 2 h reaction time. © 2011 Canadian Society for Chemical Engineering

Sargassum algae has become a major environmental issue due to its abundance in the Pacific Ocean with hundreds of tons reaching the beaches of the Mexican Caribbean every year. This generates large quantities of decomposing organic matter that have a negative impact on the region's economy and ecosystems. Sargassum valorization has turned out to be a fundamental aspect to mitigate its environmental impact. This study proposes the use and application of untreated Sargassum biomass for the decontamination of waters polluted with lead (Pb) and cadmium (Cd) through single and binary adsorption tests. Physicochemical and textural properties examined by SEM, XRD, and FT-IR elucidated that Sargassum biomass is viable to be used as a potential environmental benign adsorbent, exhibiting Cd(II) and Pb(II) adsorption capacities as high as 240 mg g−1 and 350 mg g−1, respectively, outperforming conventionally used adsorbents. This is attributed to its morphology, favorable surface charge distribution, and the presence of -OH and -COH groups. A strong affinity between the biomass and metal pollutants was evidenced by a thermodynamics study, showing a spontaneous and endothermic process. This work sets a practical route for the utilization of the Sargassum biomass, demonstrating its applicability as a potential material for heavy-metal-polluted water remediation, making a substantial contribution to a circular economy system.

No abstract

<p>Ectoparasite control in the livestock sector involves the use of chemicals to prevent production losses. In small farms that produce milk in the Córdoba department, the use of the pumping system for the cattle bath is common between farmers. In this work, cypermethrin degradation efficiency was evaluated in three lab-scale subsurface flow constructed wetland planted with Limnocharis flava, Cyperus papyrus and Alpinia purpurata sp., and one unplanted system, all of the beds were gravel based; then, total suspended solids and total phosphorus retention, and elimination of chemical oxygen demand were measured as water quality parameters. The wastewater was pretreated in a descending-ascending slow sand filter, and then was conducted to a wetland continuous flow fed at 7 ml/min. Limnocharis flava bed was higher for the degradation of organic compounds, with 97.9 ± 2.5 % and 69.1 ± 3.7 % for cypermethrin and chemical oxygen demand respectively, with statistically significant differences (p &lt; 0,05) respect to unplanted bed. The higher SST removal were found in the Cyperus papyrus wetland, with 62,0 %, however, no differences were observed with the other evaluated planted systems, as opposed these were significantly higher than unplanted wetlands.</p>