RESUMO
Efficient recovery and regeneration of ionic liquid is significant for industrial Ionosolv pretreatment. Complicated electrolyte composition restricts the scale-up recovery and application of protic ionic liquid such as triethylammonium hydrogen sulfate [TEA][HSO4] in biomass-related research. Recovery of [TEA][HSO4] after Ionosolv pretreatment for miscanthus powder was studied using bipolar membrane electrodialysis (BMED) assisted with ultrafiltration (UF) by the divisional recovery of TEA+ as TEA and recovery of SO42- as H2SO4 in different BMED compartments. Hence accurately-controlled regeneration of [TEA][HSO4] could be realized. Influence of current density and feed concentration of BMED module was studied in detail. In this study, the highest recovery ratio for TEA+ and SO42- reached 93.7% and 96.4%. The lowest energy consumption of specific [TEA][HSO4] recovery was about 6.2 kwh/kg. Insight gained from this study suggests a potentially industrial methodology for complicated protic ionic liquid recovery after biomass processing.