Preparation of a bagasse-based anion exchange fiber for sugar decolorization

Sugar bagasse was converted into an anion-exchanger through grafting acrylamide using (NH4)2Fe(SO4)2/H2O2 as initiator in an aqueous system, followed by reacting with ethylenediamine and hydrochloric acid. The effects of the grafting conditions such as monomer concentration, temperature, reaction time on the degree of grafting were investigated. The ion exchange capacity of the sugar bagasse base anion-exchange fiber (SB-IEF) was up to 3.70 mmol/g. Application of the SB-IEF in sugar decolorization was evaluated. Compared with commercial strong basic anion exchange resin (AIER) and strong basic anion exchange fiber (AIEF), SB-IEF showed the highest static decolorization capacity for sugar colorants (decolorization degree 71.40%), followed by AIEF (decolorization degree 68.74%) and AIER (decolorization degree 31.40%) at the same operating conditions. The dynamic decolorization results indicated that SB-IEF showed larger processing volume than AIER and AIEF. SB-IEF with higher grafting degree would have a higher decolorization degree. When 200 mL 2% brown granulated sugar solution was treated with 1 g SB-IEF (grafting degree 82%), 80% decolorization degree could be achieved. The research results may provide a recyclable route for the comprehensive utilization of by-products of sucrose industry. (c) 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 201

Cascade engineering of bagasse into activated porous carbon for wide-pH-range aqueous mercury removal

Summary: Low hierarchy and disruptive functionality of carbonaceous materials from biomass pyrolysis restrict their energy and environmental applications. Here, we report a cascade strategy to engineer bagasse into activated porous carbon with regulated morphology and functional groups. The initial pyrolysis of bagasse at 350°C –850°C facilitates curve sheet morphology and random meso-/micro-porosity. The subsequent alkali calcination leads to a micropore and comb-like structure with specific surface area and pore volume of 1,276.7 m2/g and 579.5 × 10−3 cm3/g, respectively. The last acid rinse removes the remaining –OH and –COO groups on the biochar surface. As a result, activated porous carbon processed at 450°C and activated with KOH/HCl exhibits the highest adsorption capacity of 103.4 mg/g at a rapid equilibrium rate fitted with Freundlich adsorption isotherm and facilitates steady mercury removal under pH 3–11. This study provides an effective approach to engineering agricultural waste into superior adsorbents for wastewater remediation. Science for society: Mercury contamination is a significant public health and environmental problem. Cost-effective and high-performance remediation methods have gained attention in both academic and industrial fields. Agricultural waste is an attractive resource as it provides rich carbon components with a modifiable structure to manufacture commercial adsorbents, namely, activated carbon. We present an approach that overcomes the existing issues in the complex structure and composition of activated carbon from waste heating. Highly orderly and regulated biochar fabricated from bagasse—sugarcane pulp—can be used for effective mercury adsorption under different conditions. This approach may facilitate the remediation of mercury-containing wastewater in a sustainable manner

Effects of Steam Explosion on Bagasse Specific Surface Area and Grafting Degree of Acrylamide-Grafted Bagasse

The effect of steam explosion pretreatment conditions, such as steam explosion pressure, maintained pressure time, and bagasse water content, on bagasse specific surface area were investigated through single-factor experiments. After determining the optimal pretreatment conditions, bagasse graft acrylamide was prepared by grafting polymerization reaction of the acrylamide monomer onto the pretreated bagasse. The effects of surface area on the grafting degree were analyzed. Results showed that the grafting degree increased with increasing specific surface area. The optimized steam explosion pretreatment conditions were as follows: steam explosion pressure, 2.0 MPa; pressure maintaining time, 60 s; and bagasse water content, 25%

An Alternative to Vermiculite: Composting on Tropical Islands Using Coral Sand to Enhance Nitrogen Retention during Ventilation

Reducing nitrogen loss during composting with forced ventilation was comprehensively investigated in this study. Coral sand was tailored in the co-composting in the co-composting of sludge and litters. The physicochemical results revealed that forced ventilation prolonged the thermophilic phase and accelerated the substrate decomposition. With the addition of 10% native coral sand, the amount of nitrogen loss decreased by 9.2% compared with the original group. The microbial community evaluation revealed that the effect of forced ventilation on colony abundance was significantly greater than that of adding coral sand. This study demonstrated that when composting on a tropical island, adding coral sand under forced ventilation was a viable solution for realizing sustainable development