Lignocellulosics biomass biodegradation of water hyacinth and water lettuce by white rot fungi for bioethanol production

Nowadays, renewable energy has become alternative energy to reduce the consumption of fossil fuels. Therefore, lignocellulosic materials such as crop residues, grass and wood, and aquatic plants that are inedible has become potential sources for bioethanol production. In this study, water hyacinth (WH) and water lettuce (WL) were selected as potential resources of their abundance in nature and can be easily propagated and cultivated. Although these floating aquatic plants are considered as the most problematic plants due to their uncontrollable growth in water bodies worldwide, their ability to remove pollutants from wastewater has created a sustainable approach for their use in phytoremediation and further use as biomass substrates for bioethanol production. The use of phytoremediation by implementing invasive floating aquatic plants can support the sustainable management of wastewater treatment in the future. This study aims to determine the potential of WH and WL as bioindicators for phytoremediation and at same time to produce a high amount of sugar consumption for bioethanol production. In addition, this study emphasizes the biodegradation of WH and WL by white-rot fungi collected from decayed wood and soil. White-rot fungi have the ability to degrade lignin, hydrolyze cellulose, and hemicellulose, and ferment alcohols for bioethanol production. Trichoderma citrinoviride M3, Schizophyllum commune M8, and Pestalotiopsis sp. M12 were selected from twelve fungal species on the basis of rapid growth rate after five days of incubation and further use for degradation of lignocellulosic materials from water hyacinth and water lettuce and for bioethanol production. These fungal species were identified by morphological characterization and 18S rRNA sequence analysis. To date, the use of biological pretreatment using T. citrinoviride M3, S. commune M8, and Pestalotiopsis sp. M12 with regard to water hyacinth and water lettuce substrates as well as its further use for the fermentation process to produce bioethanol has not been explored before. The parameters involved are sugar content by the dinitrosalicylic acid (DNS) Method, the determination of lignin by the Klason Method, the determination of cellulose and hemicellulose by the Chesson Method, and the determination of bioethanol by Gas Chromatography (GC). The results showed that both WH and WL indicated the same correlation trend between biomass growth and sugar content, as the sugar content increased when the plants reached the highest growth. However, WH has more extractable sugar than WL, which is more significant because fermentable sugar is needed for the fermentation process to produce bioethanol. The results also showed that T. citrinoviride M3 has the highest rate of degradation of lignocellulosic materials compared to S. commune M8 and Pestalotiopsis sp. M12. Therefore, T. citrinoviride M3 was selected for further investigation to evaluate the simultaneous saccharification and fermentation process for bioethanol production. The results showed that WH and WL produced 8.6 g/L and 7.4 g/L yield of ethanol, respectively, proportional to the fermentation time, with an increasing time of up to 96 hours. Overall, it can be concluded that WH is a promising biomass when the simultaneous co-cultivation of T. citrinoviride M3 with S. cerevisiae is used for bioethanol production and the fermentation process is fully optimized. The findings of this study would be beneficial for future investigation, especially in exploring the potential production of bioethanol from phytoremediation technology systems

The phytoremediation using water hyacinth and water lettuce : correlation between sugar content, biomass growth rate, and nutrients

Degradation of water quality due to the presence of pollutants in water is an emerging issue in many countries, including Malaysia. Phytoremediation is one of the environmentally friendly, cost-effective conventional technologies that are still used in modern times. However, the selection of plant species is the most important aspect for the application of phytoremediation in wastewater treatment. Nevertheless, there are species of floating aquatic macrophytes that are capable of coping with various pollutants present in wastewater. Among the various floating aquatic macrophyte species, water hyacinth (WH) and water lettuce (WL) have been described as effective phytoremediators in reducing water pollution through bioaccumulation in their body tissues. Hence, WH and WL were chosen in this study as it is easily found, propagated, and cultivated. This paper aims to determine the biosorption capacity of these species in eliminating various pollutants present in wastewater as well as to define the optimum harvesting time for each species. Although these floating aquatic macrophytes are considered the most problematic plants due to their uncontrollable growth in water bodies worldwide, their ability to remove pollutants from wastewater has created a sustainable approach for their use in phytoremediation. In this sense, the use of phytoremediation by implementing the invasive floating aquatic macrophytes can certainly support the sustainable management of wastewater treatment in the future. Based on the results, it was found that WH efficiently removed higher PO4 3-, NO3 - and NO2 - concentrations compared to WL from the wastewater. Both WH and WL showed the same trend of correlation between the growth rate and sugar content, where the sugar content increased when the plants reached the highest growth rate. The maximum nutrient uptake occurred in 14-17 days, proving that nutrient availability is critical for plant growth. This study concludes that the sugar content of WH and WL are increased with the biomass growth rate, and both plants species are competent in eradicating the nutrient pollution in wastewater. On top of that, this study infers that the maximum harvesting period for WH biomass is on day 18, while WL biomass is on day 21; based on the highest sugar content and biomass weight of each species

Utilization of Baggase Waste Based Materials as Improvement for Thermal Insulation of Cement Brick

Building materials having low thermal load and low thermal conductivity will provide thermal comforts to the occupants in building. In an effort to reduce the use of high energy and waste products from the agricultural industry, sugarcane bagasse and banana bagasse has been utilize as an additive in the manufacture of cement brick. The aim of this study is to investigate the insulation and mechanical properties of brick that has been mixed with bagasse and its effectiveness as thermal insulation using heat flow meter. Waste bagasse is being treated using sodium hydroxide (NaOH) and is characterized using SEM and XRF. The samples produced with two different dimensions of 50 mm × 50 mm × 50 mm and 215mm × 102.5mm × 65mm for thermal conductivity test. Next, the sample varies from 0% (control sample), 2%, 4%, 6%, 8% and 10% in order to determine the best mix proportion. The compressive strength is being tested for 7, 14 and 28 days of water curing. Results showed that banana bagasse has lower thermal conductivity compared to sugarcane bagasse used, with compressive strength of 15.6MPa with thermal conductivity 0.6W/m.K

Utilization of Baggase Waste Based Materials as Improvement for Thermal Insulation of Cement Brick

Building materials having low thermal load and low thermal conductivity will provide thermal comforts to the occupants in building. In an effort to reduce the use of high energy and waste products from the agricultural industry, sugarcane bagasse and banana bagasse has been utilize as an additive in the manufacture of cement brick. The aim of this study is to investigate the insulation and mechanical properties of brick that has been mixed with bagasse and its effectiveness as thermal insulation using heat flow meter. Waste bagasse is being treated using sodium hydroxide (NaOH) and is characterized using SEM and XRF. The samples produced with two different dimensions of 50 mm × 50 mm × 50 mm and 215mm × 102.5mm × 65mm for thermal conductivity test. Next, the sample varies from 0% (control sample), 2%, 4%, 6%, 8% and 10% in order to determine the best mix proportion. The compressive strength is being tested for 7, 14 and 28 days of water curing. Results showed that banana bagasse has lower thermal conductivity compared to sugarcane bagasse used, with compressive strength of 15.6MPa with thermal conductivity 0.6W/m.K

Kinetic and equilibrium studies for dye adsorption onto sugarcane Bagasse and rice husks

The textile industry discharges large quantities of highly colored wastewater from industrial processes using chemical components. Many dyes are designed to be chemically stable so that they are difficult to decolorize due to their complex structure and synthetic origin. The dye waste is subsequently released directly to water bodies during the textile finishing process. This improper released has adverse effects on the environment and may reduce photosynthesis in aquatic plants. Even though adsorption techniques have been widely used to remove textile dye from waters, the kinetic models used to describe the adsorption of textile dye onto a porous material is still not yet fully understood. This study investigated different applications of absorbent from sugarcane bagasse (SB) and rice husks (RH) in removing color from aqueous solution and the application of kinetic model for adsorption of color from aqueous solutions onto SB and RH. A batch study was carried out under various mass of adsorptions and contact time with constant with the initial concentration of aqueous solution was 400ADMI. The data obtained from batch experiments showed that the removal of RH (93%) was more efficient than SB (49%). This study also advanced the understanding on the kinetic adsorption study of RH and SB to prove that the adsorbents have potential to reduce dye from synthetic solution. The contribution of this study in the removal of significant dye pollutants from industrial wastewater will require future assessment in a prospective wastewater treatment facility setting

Adsorption isotherms and kinetics of phosphate on waste mussel shell

In this study, removal of phosphate (PO43−) from aqueous solutions using waste mussel shell (WMS) was examined. The physicochemical characteristics of WMS were identified. In the batch experiments, the effects of contact time and adsorbent dosage (m) on the PO43− adsorption by the WMS were scrutinised. The maximum PO43− removal efficiency (E) was 83.4% at 144 h contact time for WMS dosage of 10 g. A comparison of kinetic models applied to the adsorption of PO43− onto WMS was evaluated using pseudo-first-order (PFO) and pseudo-second-order (PSO) kinetic models. The experimental data was fitted well with the PSO kinetic model. In the isotherm studies, Langmuir and Freundlich isotherm models were applied. The Langmuir isotherm model was well described with the PO43− adsorption. The results indicated that WMS has a good potential to adsorb PO43− from water and thus could improve environmental quality. Furthermore, this study investigated on how the Langmuir isotherm for basic adsorption could be applied to predict E or required m under a given set of initial conditions (i.e., initial solute concentration, solution volume, and adsorbent dosage). This was accomplished by combining the Langmuir isotherm with mass balance of solutes between liquid solution and solid adsorbent phases