Table 1 - Overview of recent literature illustration on the use of hydrodynamic cavitation reactors to pretreat the various lignocellulosic biomass feedstocks
Raw material (particle size) | Cavitation device | Biomass Placement | Processing parameters | Main results | References |
|---|---|---|---|---|---|
Reed (10 mm) | Orifice plate (27 holes of 1 mm of diameter | Cavitation zone (woven wire cloth 40 mesh) | 3% NaOH, 11.8% solid loading, 41.1 min, operating temperature 77 °C, inlet pressure 500 kPa | Lignin removal 35–42%, sugar released 326.5 g/kg of raw reed, 85% of cellulose hydrolised in 72 h. Energy consumption 3.65 MJ/kg of reed | Kim et al. 2015 |
Sugarcane bagasse (1.18–1.70 mm) | Orifice plate (27 holes of 1 mm of diameter | Cavitation zone (cylindrical wire cloth 40 mesh) | 0.48 M NaOH, 4.27% solid loading, 44.48 min, operating temperature 64 °C, inlet pressure 300 kPa | Lignin removal 60.4%, glucan content 52.1%, 97.2% of cellulose hydrolised in 48 h | Hilares et al. 2016 |
Corn stover (0.25 mm) | Venturi tube (1.8 mm of throat diameter, length 40 mm) | Biomass slurry (Mixed with catalyst and circulated in a closed loop) | 0.4 mol/L of Na2CO3 + 0.6 mol/L of H2O2, 4% solid loading, 60 min, operating temperature 30 °C, inlet pressure 220 kPa | Lignin removal was verified by FTIR analysis by reduction in the band 1745 and 1606 cm−1. Pretreatment efficiency 2.24.10–5 g glucose/J | Nakashima et al. 2016 |
Sugarcane bagasse (10 mesh) | Venturi tube (7.14 mm of throat diameter, length 225.5 mm—15% opening) | Biomass slurry (Mixed with catalyst and circulated in a closed loop) | Ca(OH)2 0.1 g/g of dry biomass, 1% solid loading, 120 min, operation temperature 22 °C, inlet pressure 446 kPa | Changes in composition were measured by crystallinity index. 46% of cellulose hydrolised in 72 h. Sugar released 325 g/kg of raw biomass. Energy consumption 12.8 kJ/g sugar | Madison et al. 2017 |
Sugarcane bagasse (4.7 mm) | Orifice plate (16 e 27 holes of 1 mm of diameter) | Cavitation zone (cylindrical wire cloth 18 mesh) | 0.3 M NaOH, 3 bar, 70  °C, 30 min | Lignin removal 41.83%. 93.05% hydrolysis yield of cellulose and 94.45% hydrolysis yield of hemicellulose in 30 min of pretreatment | Hilares et al. 2017a |
Sugarcane bagasse (4.7 mm) | Orifice plate (16 holes of 1 mm of diameter) | Cavitation zone (cylindrical wire cloth 18 mesh) | The alkalis sodium carbonate Na2CO3 (0.5, 1.0 and 1.5 mol/L), calcium hydroxide Ca(OH)2 (0.5 mol/L), potassium hydroxide KOH (0.1, 0.3 and 0.5 mol/L) and sodium hydroxide NaOH (0.3 mol/L), 60 °C, 20 min | In process using NaOH-HC pretreatment: 45.57% lignin removal, 21.98% hemicellulose removal, 62.33% of total carbohydrate fractions were hydrolyzed and 17.26 g/L of ethanol production (0.48 g of ethanol/g of glucose and xylose consumed) was achieved | Hilares et al. 2017b |
Corn cob (≤ 212 μm) | Orifice plate (9 holes of 2 mm of diameter | Biomass slurry (Mixed with acetate buffer and circulated in a closed loop) | Laccase enzyme 6.5 U/g of biomass, 5% solid loading, 60 min, operating temperature 30 °C, inlet pressure 50 kPa | Lignin removal 47.4%, cavitational yield 3.56.10−5 g/J. Energy consumption 1.35 MJ/kg of biomass | Thangavelu et al. 2018 |
Cattle Manure and Wheat Straw (2.0 mm) | ARHCR | Worked in a batch mode. Number of cycles per day = 48 | Eletric motor 4 kW, 2800 rpm, 35 °C, | Enhanced biogas production to 460 L methane/kg volatile solids. Net energy output 61 kWh/d | Zieliński et al. 2019 |
Conifer and Eucalyptus pulp | ARHCR | - | 6000 rpm, 15.2 L/min, 98 kPa, 9 min, T = 34 °C, 3% solid loading | Paper with tensile index 50.5 kN m/kg, burst index at 3 kPa.m2/g. Energy consumption 58.4 kWh/m3 | Kosel et al. 2019 |
Sugarcane bagasse (< 0.250 mm) | Venturi tube (1.5 mm of throat diameter, length 40 mm) | Biomass slurry (Mixed with catalyst and circulated in a closed loop) | 4.9% NaOH, 2.03% solid loading, 58.33 min, operating temperature 65 °C, inlet pressure 300 kPa | Lignin removal 56.14%, 97.2% enzymatic hydrolysis yield at the optimal condition obtained by RSM | Bimestre et al. 2020 |
Corncob (≤ 212 μm) | Orifice plate | Biomass slurry (Mixed with acetate buffer and circulated in a closed loop) | Laccase enzyme 6.5 U/g of biomass, 5% solid loading, 60 min, operating temperature 70 °C | Lignin removal 64.1%, Hemicellulose removal 6.57%, saccharification efficiency of 55% with multifunctional cellulases at 50 °C and pH. 5.0 | Ganesan et al. 2020 |
Sugarcane bagasse (10 mesh) | Vortex based cavitation device | Biomass slurry (Mixed with catalyst and circulated in a closed loop) | Solid loading 1% w/v, 1.2m3/h, 100 passes at 30 °C, 0.75 M NaOH, 60 min | Lignin removal 77.4%, 75.5% ± 1.9 g/L glucose was released with 70.3% Cellulose hydrolysis, hemicellulose conversion 69.4% | Nalawade et al. 2020 |
Wheat straw (< 0.05 mm) | ARHCR | Biomass slurry (Mixed with catalyst and circulated in a closed loop) | 3000 rpm, 50 °C, 0.4% NaOH, solid–liquid ratio 1:50, 30 min | Lignin removal 24.05% | Lauberte et al. 2021 |
Miscanthus × giganteus stalks (5 mm) | ARHCR | Biomass slurry (Mixed with catalyst and circulated in a closed loop) | 0.3 M KOH, 2200 rpm, 20 min, 7% solid loading, Room Temperature | Lignin removal 41.54%. Paper with Tensile index 24.88 N m/g, burst index at 0.92 kPa m2/g | Tsalagkas et al., 2021 |