Soybean hulls as a low‐cost biosorbent for removal of methylene blue contaminant

Abstract

Methylene blue is a cationic dye used for dyeing cotton, wool, and silk. This dye can cause impacts when reaching water resources due to the reduction of sunlight infiltration, besides the health problems if ingested. Therefore, the complete removal of this contaminant in industrial effluents is indispensable. Currently, soybean hulls residues are used in animal feed supplementation; however, since soybean oil production is large, expressive quantities is discarded in landfills. Thus, the present study aim is to evaluate the adsorption capacity of methylene blue onto soybean hulls as an alternative use of this agroindustrial residue. The material was characterized through morphological and chemical analysis which showed porosity, heterogeneity, and functional groups that favor the adsorption. Due to the mainly negative charge of the surface, the pH did not affect the cationic dye uptake, enabling a wide pH range. After the adsorption studies, the best experimental conditions were at temperatures of 298 K, mass of 0.025 g, and contact time of 180 min, resulting in the maximum adsorption capacity of 169.90 mg g−1. When compared with other low‐cost biosorbent and activated carbons, it can be perceived a potential applicability of soybean hulls in wastewater treatment as an alternative use.

Opportunities for the Use of Brazilian Biomass to Produce Renewable Chemicals and Materials

“…used ground soybean hull (350 μm) without any acid or thermal treatment as a biosorbent for the removal of methylene blue (MB). The hull showed excellent results, with a maximum MB adsorption of 170 mg g −1 at 25 °C and neutral pH after a contact time of 3 h. These results compare favourably to those obtained from cucumber peel, rice husk, banana peel and orange peels, which adsorb MB at 111, 41, 21 and 19 mg g −1 , respectively [86] …”

“…The hull showed excellent results, with a maximum MB adsorption of 170 mg g À 1 at 25°C and neutral pH after a contact time of 3 h. These results compare favourably to those obtained from cucumber peel, rice husk, banana peel and orange peels, which adsorb MB at 111, 41, 21 and 19 mg g À 1 , respectively. [86] Nanofibrillated cellulose (NFC) has been produced from soybean hull using an eco-friendly process with peracid as a bleaching agent, followed by an extrusion step using a 2 % w/w H 2 SO 4 solution and a further deagglomeration step via sonication. The NFC produced from this process possessed a cellulose content of 92 % and a crystallinity index of 73 %.…”

A utilização de resíduos agroindustriais para adsorção do corante azul de metileno: uma breve revisão / The use of agro-industrial waste for adsorption of the blue dye of methylene: a brief review

“…Além do milho, o Brasil também destaca-se na produção de soja, cujo produto de maior demanda é o grão, utilizado na extração do óleo, gerando resíduos como farelo e cascas. Usualmente, as cascas são destinadas como ingrediente de ração animal, porém a produção de soja é tão expressiva, que grande parte dos resíduos não são utilizados e são descartados em aterros sanitários (CUSIOLI et al, 2019;SANTOS et al, 2020) de agave e alfafa in natura, obtendo capacidade adsortiva de 156,2 mg g -1 e 202,6 mg g -1 , respectivamente. Já Alfredo et al (2015), realizaram estudos com a casca de batata, tendo em vista que, em torno de 35% da batata que é produzida, acaba sendo descartada no processo de industrialização.…”

Non-Woven Fabrics Based on Nanocomposite Nylon 6/ZnO Obtained by Ultrasound-Assisted Extrusion for Improved Antimicrobial and Adsorption Methylene Blue Dye Properties

“…Methylene blue is a cationic dye used for dyeing cotton, wool, and silk. This dye can cause impacts when reaching water resources due to the reduction in sunlight infiltration, in addition to health problems if ingested [ 2 ]. The spread of infectious diseases generated by pathogenic microorganisms in water has become one of the most severe public health problems worldwide.…”