Abstract This study aimed to utilize black rice husk, an agricultural waste with significant environmental impacts, to produce a biosorbent. In this way, black rice husk, which would otherwise be released into the environment as agricultural waste, was transformed into a useful material, and its use as a biosorbent for removing methylene blue, a cationic dye, was investigated. A biosorbent was prepared from black rice husk via thermal carbonization, with H 3 PO 4 (1:2 by mass) as the activation agent. Experimental data showed that the Langmuir isotherm, with a correlation of 0.9997, provided a better fit. Furthermore, the Brunauer–Emmett–Teller test result showed that the surface area of the biosorbent was 295.35 m 2 g −1 . Additionally, response surface methodology was used to determine the interactive and individual effects of various parameters, including contact time, biosorbent dose, and solution pH, on methylene blue dye removal. The experimental results show that the biosorbent derived from black rice husk has strong potential as an environmentally friendly, cost‐effective adsorbent for dye removal. This study is the first to report the use of a biosorbent synthesized by treating black rice husk, an agricultural waste, with H 3 PO 4 as an activation agent to remove methylene blue dye.
Abstract This study investigated the effects of ferulic acid esterase‐producing Lactiplantibacillus plantarum (LP) and fibrolytic enzyme on the fermentation quality, lignocellulose degradation, and microbial community of Sudangrass ensiled with different moisture contents. Sudangrass was ensiled at three moisture levels: low (LM, 70%), medium (MM, 76%), and high (HM, 83%), and subjected to one of four treatments: control (CK); LP; cellulase and xylanase mixture (CX); or a combination of LP, cellulase, and xylanase (LP + CX). Results showed that under most conditions, LP + CX generally produced the highest lactic acid (LA) and water‐soluble carbohydrate content, the lowest value of pH, ammonia nitrogen, neutral detergent fiber, and acid detergent fiber contents compared with CK, LP, and CX. Moisture content significantly modulated these effects: LM promoted LA content, resulting in a significantly lower pH, whereas MM was most conducive to lignocellulose degradation and led to a higher relative abundance of Lactiplantibacillus and a lower abundance of Enterobacter . These results indicate that moisture content critically modulates the efficacy of microbial and enzymatic additives, with LM favoring LA fermentation and MM improving fiber degradation and saccharification. Optimizing moisture content thus offers a viable strategy to enhance silage quality for sustainable biomass utilization by adopting LM for feed production and MM for fiber saccharification.
The search for alternative and sustainable energy sources becomes urgent as energy demand increases and fossil fuels become less available, especially in water-scarce regions such as the Brazilian semi-arid region, where current projections of global warming and the expansion of arid and semi-arid zones point to a future of desertification. Prickle pear is a forage Cactaceae adapted to arid environments due to its crassulacean acid metabolism, standing out as a promising plant for biogas production. Its high water use efficiency, low lignin content, and high soluble carbohydrate and mucilage content favor anaerobic digestion without the need for costly pretreatments. The biogas production potential from the anaerobic digestion of the Orelha de Elefante Mexicana variety, cultivated at the Agronomic Institute of Pernambuco, was evaluated through the physical-chemical characterization of the biomass and biochemical methane potential tests, with three organic loads of volatile solids (5, 10, and 15 g VS L-1) over three sequential cycles, creating a recycling-type experiment. The 5 g VS L-1 load resulted in the highest biogas yield (0.391 L g-1 VS-1) and the highest-quality gas, achieving 63.8% methane in the third cycle. The identification of the predominant microorganisms in the process through metagenomic analysis provided insights into process optimization and a better understanding of the microbial ecology involved. The results highlight the potential of forage cactus as a viable and sustainable alternative for bioenergy generation in the Brazilian semi-arid region, contributing to the diversification of the regional energy matrix.
Existing monitoring frameworks for sustainability certification schemes and labels (CSLs) have largely prioritised environmental aspects, while the social and economic pillars of sustainability remain comparatively underdeveloped. Also, dedicated circularity requirements tailored to biobased systems are still largely lacking, despite being highly relevant for steering the transition to a sustainable circular bioeconomy. The work presented closes these identified gaps through the development of a structured and holistic set of sustainability principles, criteria and requirements for industrial biobased systems under four categories: environment, social, economic and circularity, distinguishing between mandatory, basic and advanced (i.e. aspirational) requirements to stimulate continuous improvement of CSLs. These are incorporated in the Content level of the newly developed BIOBASEDCERT Monitoring Tool (BMT), designed to assess the comprehensiveness of sustainability and circularity requirements in existing CSLs for industrial biobased value chains. This paper presents the Content level BMT and its testing on a selection of CSLs covering different biobased feedstocks and sectors. The tool was tested in close cooperation with CSL owners across three groups of CSLs: (1) schemes for biobased products; (2) schemes for biological feedstocks; and (3) Type I ecolabels. The results highlight the importance of a clear scope definition to identify applicable requirements for evaluation. Opportunities for improvement were identified for each group of CSLs, aiming to encourage CSL owners to improve the coverage and ambition level of their systems. The Content level BMT can be utilised for strengthening and harmonising sustainability requirements in existing CSLs, and as input to future legislation for a sustainable circular bioeconomy.
In this study, sol-gel and zeolite-based catalysts were prepared for the conversion of glucose to lactic acid under hydrothermal conditions and their activities were investigated. SiO2-supported catalysts containing different metal structures, such as Al, Fe, Cr, Sn, and Zn representing Lewis acid structures, were synthesized by sol-gel method. Beta H zeolite and USY H zeolite, as well as Sn-USY and Zn-USY zeolites, were used as zeolite catalysts. X-ray diffraction, Brunauer-Emmett-Teller surface analysis, and scanning electron microscopy analyses were performed to characterize the highly active Zn/SiO2 and USY zeolite catalysts. The highest lactic acid yield of 34.8% was obtained with the Zn/SiO2 catalyst among the SiO2-supported sol-gel catalysts at 180 degrees C for 2 h under 3 MPa N2 pressure. Among the zeolite catalysts, the highest lactic acid yields of 48.3% and 43.8% were obtained with the USY H zeolite and the Zn-USY zeolite catalysts, respectively.
