Table 2.
The optimal conditions for separating chitin from different sources using deep eutectic solvents.
| Resources | HBA | HBD | Molar Ratio (HBA:HBD) |
S/L | Temp. (°C) | Time | Ref. |
|---|---|---|---|---|---|---|---|
| Lobster shells | Choline chloride | Malonic acid | 1:2 | 1:10 | 50 | 2 h | [93] |
| 1:14 | [92] | ||||||
| Lactic acid + Glycerol | 1:1:1 | 1:20 | [94] | ||||
| Shrimp shells | Betaine HCl | Urea | 1:2 | 1:20 | After 10% CA & microwave | 7 min | [104] |
| Choline chloride | Citric acid | 1:3 | 1:20 | 80 | 2 h | [102] | |
| DL–Malic acid | 1:2 | 1:20 | 130 | 3 h | [96] | ||
| 1:3 | 80 | 2 h | [102] | ||||
| Ethylene Glycol | 1:2 | 1:20 | After 10% CA and microwave | 7 min | [104] | ||
| Glycerol | 1:2 | 1:20 | After 10% CA and microwave | 7 min | |||
| 1:29 | 100 (+7.5% AA at 120) |
3 h (1 h) |
[101] | ||||
| Tartaric acid | 1:3 | 1:20 | 80 | 2 h | [102] | ||
| Lactic acid | 1:1 | 1:50 | 60 | 6 h | [97] | ||
| 1:1 | 1:20 | 80 | 2 h | [102] | |||
| 1:2.5 | 150 | 6 h | [100] | ||||
| Malonic acid | 1:2 | 1:25 | 80 | 2 h | [95] | ||
| TsOH | 1:2 | 1:20 | 70 | 3 h | [98] | ||
| Urea | 1:2 | 1:20 | After 10% CA and microwave | 7 min | [104] | ||
| N-Methylacetamide | N-Methylurea, Acetic acid | 1:1:3 | 1:30 | Room temp. | 48 h | [105] | |
| Crab Shells | Choline chloride | Lactic acid | 1:1 | 1:25 | 130 | 2 ** h | [79] |
| Lactic acid + Glycerol | 1:1:1 | 1:20 | 80 | 2 h | [110] | ||
| 1:1.5:0.5 | |||||||
| Lactic acid | 1:2 | 1:20 | 80 | 2 h | |||
| 1:25 | 120 | [108] | |||||
| Malic acid + Glycerol | 2:1:1 | 1:20 | 80 | 2 h | [110] | ||
| 2:1.5:0.5 | |||||||
| Malic acid | 1:1 | 1:20 | 80 | 2 h | |||
| 1:30 | Microwave | 11 min | [106] | ||||
| Malonic acid | 1:2 | 1:25 | 120 | 2 h | [108] | ||
| N-acetyl-D-Glucosamine + Formic acid | 1:0.6:1.4 | 1:20 | 130 | 3 h | [82] | ||
| Cystine | Gluconic acid | 5:1 | 1:20 | 100 | 6 h | [107] | |
| TEBAC | Lactic acid | 1:27 | 1:20 | 120 | 6 h | [111] | |
| Crayfish shells | Betaine | Lactic acid | 1:2 | 1:20 | 115 | 20 h | [112] |
| Choline chloride | Lactic acid | 1:2 | 1:20 | 115 | 20 h | ||
| 1:10 | 1:10 | Microwave at 120 | 0.5 h | [113] | |||
| Proline, Urea/75% DBU | 1:2 | 1:20 | 110 (+20% LA at 50) |
20 h (1 h) |
[114] | ||
| Prepupae | Betaine | Urea | 1:1 | 1:10 | 80 | 2 h | [115] |
| Choline chloride | Lactic acid | 1:2 | 1:10 | 80 | 2 h | ||
| Mushrooms | Betaine | Urea | 1:2 | 1:20 | Ultrasonic | 1 h | [117] |
| Choline chloride | Acetic acid | 1:2 | 1:20 | Microwave | 9 min | [118] | |
| Squid pens | Choline chloride | Malonic acid | 1:2 | 1:25 | 80 | 2 h | [120] |
| Potassium carbonate | Glycerol | 1:5 | 1:25 | 120 | 2 h | [119] | |
| 1:10 | 1:20 | 80 | 4 h | [121] | |||
AA: Acetic acid; CA: Citric acid; DBU: 1,8-Diazabicyclo [5.4.0] undec-7-ene; LA: Lactic acid; TEBAC: Triethylbenzylammonium chloride; TsOH: p-Toluenesulfonic acid monohydrate. **: After a certain period of DES isolation, H2O is added and mixed until reaching room temperature.