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• Diluent and temperature-swing regeneration processes applied for extraction of succinic acid with TOA and TOPO in MIBK. • Swing in acid distribution between extraction and regeneration more important than acid distribution itself. • Regeneration process based on gaseous anti-solvent ethane is most efficient, requiring only 21% of the energy of evaporation. • Combination of evaporation of MIBK and temperature-swing strongly reduces required energy input and results in higher product purity. Solvent regeneration processes for liquid-liquid extraction of succinic acid (HSuc) from aqueous streams were investigated. Tri -n- octyl amine (TOA) and tri -n- octyl phosphine oxide (TOPO) in methyl isobutyl ketone (MIBK) showed good extraction. For 20 wt% TOA in MIBK, addition of pentane at anti-solvent-to-solvent ratio of 1 (vol/vol) decreased K D from 10.2 to 0.46, applying ethane at 30 bar decreased K D to 0.45 and increasing the temperature to 60 °C decreased K D to 1.6. Evaporation of MIBK from a solvent of 40 wt% TOA in MIBK decreased K D from 10.2 to 4.0. For these processes, capital investments and energy requirements were calculated for 10 kiloton per year at a concentration factor of 5. Costs of all processes to obtain the product at maximum solubility are less than evaporation (2600 kJ/kg product at maximum solubility). A combination of a swing in diluent and temperature results in higher product concentrations after back-extraction, and reduced the energy input to obtain the pure HSuc to 19 MJ/kg. The ethane-based process is most effective with 13 MJ/kg to obtain the pure HSuc product. Although additional capital investments for compressors and pumps are required, only 110 days of production are required for return on investments. [ABSTRACT FROM AUTHOR]