Browsing by Author "Barra-Hinojosa, Julio Alexis"

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Assessment of the Hazard and Ecotoxicity of the Residues of Paiche Leather Dyed with Natural and Synthetic Colourants: A Focus on Environmental Sustainability
(idd3, 2024-5-17) Marrufo-Saldaña, Liliana Del Rosario; Paucar-Palomino, Michel Jazmín; Barra-Hinojosa, Julio Alexis; Requena-Sánchez, Norvin Plumieer
The aim of this research was to assess the hazardousness and ecotoxicity of paiche leather (Arapaima gigas) dyed with natural colourants (turmeric and purple corn) versus synthetic colourants (anilines). To determine hazardousness, the methodology included the assessment of flammability, corrosivity, reactivity to H2S and HCN, toxicity from metals, and organic compounds of dyed leather. Additionally, its ecotoxicity was determined using the California red worm (Eisenia fetida) as a bioindicator through a bioassay, with treatments at 0.02, 0.04, 0.08, 0.16, and 0.20 g of leather/g of substrate, including undyed leather and a negative control in the investigation. The hazardousness analysis results indicated that leather samples dyed with both natural and synthetic colourants are not hazardous. However, the concentrations of chromium, nickel, cadmium, and lead exceed the permitted values for their use in footwear according to the European Union. Regarding ecotoxicity, the results demonstrate that acute toxicity to E. fetida is lower for natural colourants compared to synthetic colourants, where 100% mortality occurs at concentrations between 0.04 and 0.08 g of leather/g of the substrate. Concerning chronic toxicity, after 12 weeks of exposure, the tolerance concentration for undyed paiche leather is 0.035 g of leather/g of the substrate, and for leather dyed with purple corn and turmeric, it is 0.2 g of leather/g of the substrate. It is shown that the active compounds of natural colourants have a positive effect on worm survival, and it is concluded that paiche leather dyed with these colourants presents environmental advantages over leather dyed with synthetic colourants.
Combining Effluent Treatment Methods to Remove Ammonia Nitrogen from Tannery Wastewater
(Wydawnictwo Naukowe Gabriel Borowski (WNGB), 2024-12-1) Aguilar-Ascón, Edwar; Marrufo-Saldaña, Liliana; Barra-Hinojosa, Julio Alexis
This study assessed the removal efficiency of ammonia nitrogen from tannery wastewater by combining electrocoagulation, ozonation, and ion exchange technologies. For this purpose, an electrocoagulation reactor equipped with aluminum electrodes, an ozonation tank, and a filtration system with zeolite were employed. The electrocoagulation treatment applied the response surface methodology with a 3k factorial design with the following two factors: current intensity (I) ranging from 3 to 7A, and treatment time (t) from 10 to 30 min; the removal percentage of total suspended solids (TSS) is set as a response variable. Results indicate that the treatment time and current intensity were significant for the removal of total suspended solids TSS, at a confidence level of p < 0,05. Under these conditions, a TSS, removal efficiency of 98% was achieved. Through the electrocoagulation process, the chemical oxygen demand (COD) was reduced by 58%, while in the ozonation tank, an additional 23% of COD was removed. The filtration stage demonstrated that 13X HP zeolite can exchange ions with the ammonia nitrogen from tannery wastewater, wherein a 39% removal efficiency is reached at equilibrium. Thus, the integration of various treatment methods is a viable alternative to reduce wastewater from the tannery industry. The novelty of this research lies in the integration of three methods for treating tannery wastewater. The results show that the combination of these treatments provides a more effective solution for removing the pollutant load, especially nitrogen, compared to the use of individual treatment methods alone. The study opens new perspectives for optimizing multi-stage treatment processes. © 2025 Elsevier B.V., All rights reserved.
Evaluation of the Dyeing Process for Paiche (Arapaima Gigas) Leather Using Colorant Extracted from Walnut Leaves (Juglans Neotropica) for Scaling-Up
(Iran. J. Chem. Chem. Eng. (IJCCE), 2024-04-29) Saldaña, Liliana Marrufo; Lopez-Alvarez, Antony; Sueldo Rojas, Henry; Laura-Tito, Misael; Barra-Hinojosa, Julio Alexis; Uribe, Carmen L.
The technological development of paiche leather tanning is projected as a high-impact economic activity and requires the application of clean technologies, such as replacing highly toxic synthetic chemicals. This study aimed to evaluate the extraction process of naphthoquinone from walnut leaves for dyeing chrome-free tanned paiche leather and to establish the feasibility of scaling it up. The active principle extracted in an aqueous medium was characterized using HPLC chromatography and UV spectrophotometry. A factorial design was implemented to evaluate leather dyeing, and the results were scaled up at the pilot level. The factors studied were dyeing time (60, 90, and 120 minutes) and walnut dye concentration (161.6, 209.8, and 250.0 g/L), with Color Intensity in the dyed leather as the response variable. Juglone (5-hydroxy-1,4, naphthoquinone) was identified as the primary dye-producing compound with maximum absorption at 210 nm in aqueous solution. The results of the experimental design fit a linear model, with a determination coefficient (R2) of 77.36% and an adjusted coefficient of 74.34%. The values obtained for the finished leather at the pilot scale, including tear resistance (88.90 N), tensile strength (8.34 N/mm2), elongation percentage (53.76 %), dry (4/5), wet (4), and artificial sweat rub (4) and lightfastness (5), indicate that walnut-dyed leather can be used in the manufacturing of footwear and clothing. The process is technically scalable to an industrial level. © 2024 Elsevier B.V., All rights reserved.
Toxicity Assessment of Tanning Effluents Treated via Electrocoagulation and Ozonation Using a Bioassay with Lactuca sativa
(Wydawnictwo Naukowe Gabriel Borowski (WNGB), 2024-9-1) Aguilar-Ascon, Edwar; Marrufo-Saldaña, Liliana; Barra-Hinojosa, Julio Alexis
In this study, the aim is to assess the toxicity of tannery wastewater treated with electrocoagulation and ozonation to determine the suitability of the approach for application, while maintaining the environmental quality of receiving water bodies and/or sewer systems. For this, an electrocoagulation reactor and an ozonation tank were built considering current intensity (I), treatment time (T), and ozone concentration O3 as operating factors. Acute toxicity tests were conducted using Lactuca sativa L. lettuce seeds for the raw sample (MI), sample treated with electrocoagulation (EC), and sample treated with EC and ozonation (EC + OZ). The toxicity parameters assessed in this study were the absolute germination (AG), germination index (GI), and average inhibition concentration (EC50). The electrocoagulation reactor achieved 92% removal efficiency for total suspended solid (TSS) and 10% removal efficiency for chemical oxygen demand (COD) with a current intensity of 7A and a treatment time of 30 min. In addition, the COD was further reduced in the ozonation tank by 18% with an ozone dosage of 10 g/h and a contact time of 30 min. Despite these treatments, EC50 values indicated acute toxicity in all three samples. The ANOVA analysis (p value of 0.05) revealed no significant differences between the GI values for the three samples, suggesting that toxicity did not decrease substantially, despite treatment. This is attributed to the incomplete removal of the pollutant load, expressed as COD, and formation of recalcitrant and toxic compounds during treatment processes. This work demonstrates the importance of including the “toxicity” variable in the assessment of treatments to conduct them in an integral way and preserve the environmental quality of receiving water bodies. © 2024 Elsevier B.V., All rights reserved.