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Acidogenic anaerobic fermentation route was explored for the production of bioethanol and volatile fatty acids (VFA) from the press mud (PM) obtained from sugar mill. Slurry was prepared from PM having 10% of total solids and the same was hydrolyzed under acidic thermal conditions. Both press mud slurry (PMS) and pre-treated press mud slurry (PTPMS) was used as feedstock with mixed microbial consortia (MMC) and enriched mixed microbial consortia (EMMC). Mix of bioethanol and VFA were obtained in all the four cases (PMS-MMC, PMS-EMMC, PTPMS-EMC and PTPMS-EMMC), but, bioethanol and VFA yield of 0.04 g/g and 0.27 g/g, respectively obtained from PTPMS with EMMC was found to be comparatively higher. Control experiments carried out with glucose yielded bioethanol and VFA of 0.042 g/g and 0.28 g/g, respectively demonstrating that the organism was using reducible sugars in the feedstock for the generation of bioethanol by simultaneously producing the VFA from COD.

The current status and challenges associated with the production and utilization of cellulosic ethanol in Korea are reviewed in this paper. Cellulosic ethanol has emerged as a promising option for mitigating Korea's CO(2) emissions and enhancing its energy security. Korea's limited biomass resources is the most critical barrier to achieving its implementation targets for cellulosic ethanol. Efforts to identify new suitable biomass resources for cellulosic ethanol production are ongoing and intensive. Aquatic biomasses including macroalgae and plantation wastes collected in the Southeast Asia region have been found to have great potential as feedstocks for the production of cellulosic ethanol. R&D explorations into the development of technologies that can convert biomass materials to ethanol more efficiently also are underway. It is expected that cellulosic ethanol will be in supply from 2020 and that, by 2030, its use will have effectively reduced Korea's total gasoline consumption by 10%.

The influence of various solvents (H2O, CH3OH, and C2H5OH) on product distribution and nature of products during hydrothermal liquefaction of sargassum tenerrimum algae has been examined. Hydrothermal liquefaction was performed using H2O (260, 280 and 300°C) and organic solvents CH3OH and C2H5OH (280°C) for 15min. The use of organic solvents significantly increased the yield of bio-oil. In the case of liquefaction with CH3OH and C2H5OH, the bio-oil yield was 22.8 and 23.8wt.% respectively whereas the bio-oil yield was 16.33wt.% with H2O. GC-MS analysis of the liquid products indicated the presence of various organic compounds including aromatics, nitrogenated and oxygenated compounds and higher selectivity amount of ester compounds were observed in the presence of alcoholic solvents. NMR and FT-IR showed that present of solvents have an effect on the decomposition of sargassum tenerrimum algae.

Anode with good electrocatalytic capabilities is more specifically required to reduce the ohimic losses during microbial fuel cell (MFC) operation. Highly conductive polymers viz., Polyaniline (PANi) and Polyaniline/Carbon nanotube (PANi/CNT) composite were prepared by in situ oxidative chemical polymerization method. Anodes were fabricated independently by coating PANi and CNT/PANi composites on the surface of SSM. The fabricated electrodes were evaluated as anode against stainless steel mess (SSM) as cathode during MFC operation. Maximum bioelectricity generation was observed in SSM-PANi/CNT-anode with power density of 48 mW/m2 and COD removal efficiency of 80% compared with SSM-PANi-anode (38 mW/m2; 65%) and SSM-anode (28 mW/m2; 58%). Bioelectrochemical characterization of the electrode materials using cyclic voltammetry and electrochemical impedance spectroscopy showed high electrocatalytic activity of PANi/CNT composite electrode. The study concluded the efficiency of PANi/CNT composite electrodes as bioanode in operation of MFCs towards achieving increased bioelectricity production along with wastewater treatment.

The macroalgal industry is expanding, and the quest for novel ingredients to improve and develop innovative products is crucial. Consumers are increasingly looking for natural-derived ingredients in cosmetic products that have been proven to be effective and safe. Macroalgae-derived compounds have growing popularity in skincare products as they are natural, abundant, biocompatible, and renewable. Due to their high biomass yields, rapid growth rates, and cultivation process, they are gaining widespread recognition as potentially sustainable resources better suited for biorefinery processes. This review demonstrates macroalgae metabolites and their industrial applications in moisturizers, anti-aging, skin whitening, hair, and oral care products. These chemicals can be obtained in combination with energy products to increase the value of macroalgae from an industrial perspective with a zero-waste approach by linking multiple refineries. The key challenges, bottlenecks, and future perspectives in the operation and outlook of macroalgal biorefineries were also discussed.

An investigation into the influence of combined alkaline and disperser pretreatment on sludge disintegration was studied. The effects of four variables, alkalines (NaOH, KOH, Ca(OH)(2)), treatment time (15-180 min), pH (8-11) and rpm (4000-24,000) were investigated. The effect of sludge pretreatment was evaluated by COD solubilization, suspended solids reduction and biogas production. The best performances, in terms of COD solubilization, SS reduction and biogas production, were the ones that occurred for specific energy input of 4544 kJ kg(-1) TS for NaOH at pH10, were found to be 24%, 23.3% and 76%, higher than the control, respectively. Not only the increase in biogas production was investigated, excluding protein hydrolysis was also performed successfully by this combined pretreatment even at low specific energy input. Thus, this chemo-mechanical is an effective method for enhancement of biodegradability and it laid the basis to produce higher biogas quantities, to improve clean energy generation from WAS.

In present study, potentials of water hyacinth (Eichhornia crassipes) and water chestnut (Trapa bispinnosa) employed for phytoremediation of toxic metal rich brass and electroplating industry effluent, were examined in terms of biogas generation. Inability of the plants to grow in undiluted effluent directed to select 20%, 40% and 60% effluent concentrations (with deionized water) for phytoremediation experiments. Slurry of both the plants used for phytoremediation produced significantly more biogas than that by the control plants grown in unpolluted water; the effect being more pronounced with plants used for phytoremediation of 20% effluent. Maximum cumulative production of biogas (2430c.c./100gdm of water hyacinth and 1940c.c./100gdm of water chest nut) and per cent methane content (63.82% for water hyacinth and 57.04% for water chestnut) was observed at 5mm particle size and 1:1 substrate/inoculum ratio, after twenty days incubation. Biogas production was quicker (maximum from 8-12days) in water hyacinth than in water chestnut (maximum from 12-16days). The qualitative and quantitative variations in biogas production were correlated with COD, C, N, C/N ratio and toxic metal contents of the slurry used.

This study focuses on microwave-assisted pyrolysis (MAP) of fresh waste tea powder and torrefied waste tea powder as feedstocks. Solvents including benzene, acetone, and ethanol were used for soaking feedstocks. The feedstock torrefaction temperature (at 150 °C) and solvents soaking enhanced the yields of char (44.2-59.8 wt%) and the oil (39.8-45.3 wt%) in MAP. Co-pyrolysis synergy induced an increase in the yield of gaseous products (4.7-20.1 wt%). The average heating rate varied in the range of 5-25 °C/min. The energy consumption in MAP of torrefied feedstock (1386 KJ) significantly decreased compared to fresh (3114 KJ). The pyrolysis index dramatically varied with the solvent soaking in the following order: ethanol (26.7) > benzene (25.6) > no solvent (10) > acetone (6). It shows that solvent soaking plays an important role in the pyrolysis process. The obtained bio-oil was composed of mono-aromatics, poly-aromatics, and oxygenated compounds.