Preparation and properties of bio-oil from the antibiotic residue by hydrothermal liquefaction
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摘要: 探究了菌渣的水熱液化轉換成生物油燃料的過程。結果表明,抗生素菌渣在260 ℃、保留時間是135 min時,獲得最大的生物油產率(28.01%)。通過6種不同的催化劑進行催化,加入催化劑后,生物油產率最大的是Na2CO3(36.06%)和NaOH(36.31%)。堿催化的生物油的含氮化合物的質量分數在41.16%~49.74%之間,而酸催化產生的生物油含氮化合物的量在57.62%~59.32%之間。通過調節催化劑Na2CO3、NaOH的添加量發現,在投加量為8%時,生物油含氮量均最低,Na2CO3和NaOH催化產生的生物油組分的含氮化合物質量分數分別為29.12%和35.67%。在催化劑投加量為10%時,對氧的脫除效果都最好,分別為32.12%和29.02%,此時產生的生物油的熱值達到最大(達到33.3220和34.7320 MJ?kg?1)。Abstract: Antibiotic residue, a kind of biomass, is classified as hazardous waste. However, it is considered a good biomass resource because it contains rich organic matter and bacterial protein with a calorific value equivalent to that of low-rank coal. The hydrothermal method uses high-temperature liquid water as the reaction medium and reactant, which has the characteristics of high energy, fast reaction speed, large material flux, convenient feeding, and high product separation efficiency, especially avoiding the evaporation of high water content of aquatic substances. Although bio-oil obtained from the noncatalytic hydrothermal process has a high calorific value, it exhibits negative characteristics, such as high oxygen and nitrogen and high viscosity, which makes it unsuitable for use as a fuel. Therefore, catalysts are needed to improve the quality of bio-oil. This paper investigates the hydrothermal liquefaction of bacterial residues into bio-oil under a retention time of 30–240 min at 220–300 °C. Results show that the maximum yield of bio-oil is 28.01% at 260 °C for 135 min. Catalyzed by six kinds of catalysts (HCOOH, CH3COOH, K2CO3, Na2CO3, NaOH, and KOH), the highest yield of bio-oil is achieved with Na2CO3 (36.06%) and NaOH (36.31%). The content of hydrocarbons and their derivatives in the produced bio-oil is found to be relatively low at varying amounts of Na2CO3 and NaOH catalysts. The mass fraction of nitrogen-containing compounds in the alkali-catalyzed and acid-catalyzed bio-oil is 41.16%–49.74% and 57.62%–59.32%, respectively, with the best nitrogen removal obtained at a mass dosage of 8%. In particular, the contents of nitrogen compounds in the bio-oil catalyzed by Na2CO3 and NaOH are 29.12% and 35.67%, respectively. The best removal effect of oxygen is achieved at a dosage of 10%. Specifically, bio-oil components produced by Na2CO3 and NaOH contains 32.12% and 29.02% oxygen-containing compounds, respectively. Moreover, the higher heating value (HHV) of bio-oil produced with these catalysts is the largest, with an HHV of 33.3220 and 34.7320 MJ?kg?1 for Na2CO3 and NaOH, respectively.
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Key words:
- antibiotic residue /
- renewable energy /
- fuel /
- catalyst /
- hydrothermal liquefaction
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表 1 抗生素菌渣元素、工業分析(質量分數)
Table 1. Elemental and industrial analysis of antibiotic residue
% Industrial analysis Elemental analysis Volatile matter Fixed carbon Ash Water C H N S O* 75.26 8.51 7.32 8.91 47.38 6.62 6.26 0.81 36.02 Note: * is obtained by difference calculation method. 表 2 不同均相催化劑生物油產率對比
Table 2. Comparison of the bio-oil yield of different homogeneous catalysts
% Catalyst Bio-oil production rate Solid production rate Liquid production rate Gas production rate None 28.01 26.38 18.83 27.08 HCOOH 24.31 27.86 18.93 26.90 CH3COOH 23.31 28.04 21.22 27.43 Na2CO3 36.06 21.52 22.19 20.23 NaOH 36.31 25.48 22.45 23.16 K2CO3 29.05 24.89 22.32 24.14 KOH 29.01 24.91 22.12 23.96 表 3 不同催化劑催化生物油氣相色譜?質譜分析
Table 3. GC/MS analysis of bio-oil catalyzed by different catalysts
No. Retention time/min Composition Peak area/% None HCOOH CH3COOH Na2CO3 K2CO3 NaOH KOH 1 2.513 2-methoxy-1-3-phenylmethoxy-benzene 1.27 2.80 3.21 — — — — 2 2.748 glycine 1.12 12.18 12.79 — — — — 3 3.52 2,2-dimethoxybutane 1.19 2.39 5.19 — — — — 4 4.236 2,4-azacyclobutanedione 2.97 9.35 6.71 — 26.79 1.82 14.36 5 5.213 Trione trioxide 7.72 6.32 3.12 5.61 — 0.59 — 6 9.242 Carbamate — 5.67 4.16 3.05 2.73 1.66 2.56 7 15.707 Tri butyl acrylonitrile 7.12 3.18 2.19 4.07 — 1.73 — 8 17.166 Dihydromannitol 9.12 — — 3.17 — 2.46 — 9 18.301 4-ethyl-phenol 2.19 — — — — 1.50 — 10 20.072 1-isocyano-2-methyl-benzene 1.21 3.37 — 4.55 2.15 2.28 1.65 11 23.096 5-methyl-indole 6.19 3.37 5.72 9.76 5.02 2.35 1.53 12 24.21 1,2,3-triazole-4-amino-formamide 2.12 3.04 6.12 — — — — 13 25.599 1,4-anhydrous-mannitol — — — — — 3.84% — 14 26.078 2-acrylic acid-3-methylamino-methyl ester 2.19 — — — 2.06 — 2.22 15 28.349 Syringol 1.86 — — — — 4.38 — 16 30.191 l-tryptophan-dinitrophenyl 4.31 — — — — 2.96 — 17 35.851 2,5-dione-3,6-diisopropylpiperazin 2.12 3.54 6.01 — 4.44 1.72 — 18 38.203 1,4-dione hexahydro-3-pyrrolo 3.32 — — — — 2.87 — 19 39.106 1-methyl-pyrido 19.32 5.11 3.79 16.20 6.65 9.21 5.23 20 40.718 2,5-piperazinodione 3,6-bismethylpropyl 9.32 1.21 2.10 9.27 5.37 3.46 6.31 21 42.291 6-methyl-octadecane — — — — 8.75 11.49 — 22 42.966 9,12-hexadecaneate ethyl 2.12 — 12.01 — 9.48 — 20.98 23 44.006 9,12-octadecadiene ester 1.27 9.32 7.31 3.69 9.36 2.32 1.39 24 44.094 Actinomycin 0.79 0.97 0.76 0.91 0.36 0.29 0.67 25 44.239 1-heptyne-1-alcohol 1.36 — — — — 12.56 — 26 44.762 Cyclopentanone 21.19 19.04 19.56 11.88 15.87 16.54 11.78 27 45.797 9,12-octadecadienoic acid 1.21 5.60 7.21 — — — 11.51 28 46.322 Ethyl linoleate 2.12 — 1.27 — — — 8.95 29 46.871 Lauramide — — 7.88 — — — — 30 48.412 l-phenyl-cyclo 0.01 4.97 1.29 — — — — 31 48.763 Methyl-1-octadecylamine 0.19 — 5.07 — — — — 32 49.486 l-phenylalanyl-cyclo — 0.64 5.32 — — — — 33 50.573 6,9-pentadecadiene-alcohol — 9.98 9.29 11.78 16.06 3.51 9.23 表 4 不同催化劑催化產生生物油元素分析(質量分數)
Table 4. Analysis of bio-oil elements produced by different catalysts
% Catalyst C H N S O High heating value/
(MJ?kg ?1)None 65.19 8.06 9.19 1.06 12.96 30.1230 HCOOH 72.212 8.68 8.71 1.47 10.12 31.0229 CH3COOH 72.103 8.61 8.67 1.40 10.32 31.0010 Na2CO3 74.16 8.77 6.88 1.18 9.01 33.3210 NaOH 73.14 8.73 6.97 1.24 9.27 34.7390 K2CO3 73.19 8.74 7.01 1.22 9.97 32.2920 KOH 73.12 8.76 7.06 1.36 9.91 32.1980 表 5 Na2CO3不同梯度生物油成分分析(質量分數)
Table 5. Composition analysis of bio-oil with different gradients of Na2CO3
No. Retention time/min Composition Peak area/% 0% 1% 3% 5% 8% 10% 1 3.517 2,2-dimethoxybutane — — 21.85 4.13 — — 2 5.224 Trione trioxide 7.72 — — — — 5.61 3 9.235 Methyl carbamate butyl ester 1.19 1.70 2.39 1.98 4.19 3.05 4 12.481 Methyl carbamate 1.97 — 2.41 2.04 — — 5 15.69 Tri butyl acrylonitrile 7.12 1.87 — 5.86 — 4.07 6 17.189 Dihydromannitol 4.12 — — — — 3.17 7 18.3 4-ethyl-Phenol 1.12 0.98 — 2.81 — — 8 20.067 1-isocyano-2-methyl-Benzene — — 4.73 1.95 2.44 4.55 9 23.1 5-methyl-indole 1.19 2.28 — 4.59 3.71 4.73 10 25.477 alanine 7.12 — — 3.00 — — 11 26.081 2-acrylic acid,3dimethyl-ester 3.12 4.82 — 1.46 — — 12 26.099 1-ethyl-indole 6.27 — — — — 5.03 13 28.355 Syringol 9.20 — — 4.90 — — 14 35.853 2,5-dione,3,6-diisopropylpiperazin 2.12 2.79 3.16 7.32 — — 15 39.112 1-methyl-9- pyrido-indole 19.71 8.92 5.41 12.30 7.16 16.20 16 40.704 3,6methyl propyl piperazinodione 9.32 — 4.14 — 3.04 16.66 17 42.458 Ethyl hexadecanoate — — 10.18 — — — 18 44.043 Deoxyspermidine guanidin — — 4.85 — — — 19 44.094 Actinomycin — — — — — 0.67 20 44.753 Cyclopentanone 21.19 13.28 9.15 14.85 28.69 11.88 21 45.733 9,12-octadecadienoic acid 7.21 — 18.82 — — — 22 48.638 2-amino-5carboxyl-imidazole 2.12 8.29 — 7.55 — — 23 48.726 1-methyl-octadecylamine 0.72 — — — 17.32 — 24 49.783 Pyrrolo pyrazine 3.27 — — 14.10 — — 25 50.57 6,9-pentadecadiene-1-alcohol 0.02 15.07 12.91 — 23.46 11.78 表 6 NaOH不同梯度生物油成分分析 (質量分數)
Table 6. Composition analysis of bio-oil with different gradients of NaOH
No. Retention time /min Composition Peak area/% 0% 1% 3% 5% 8% 10% 1 3.521 2,2-dimethoxybutane 1.19 7.22 — — — — 2 4.245 3-diethyl-2,4-azacyclobutanedione — — — 0.37 — 1.82 3 5.229 Trione trioxide 7.72 0.55 — — — 0.59 4 9.238 butyl methyl phenyl ester 1.97 1.75 2.86 1.89 2.01 1.66 5 9.843 2-phenylpentan-3-isopropyl-alcohol — 1.22 — — — — 6 12.484 Methyl carbamate 1.97 2.23 — — — — 7 15.693 Tri butyl acrylonitrile 7.12 2.91 5.17 2.95 2.03 1.73 8 16.689 Amino propanol — — — 2.50 — — 9 17.169 Dihydromannitol 2.12 — — — 1.92 2.46 10 17.665 1,6-dicarboxylic acid-pyrido imidazole — — — 0.76 — — 11 18.296 4-ethyl-Phenol 1.20 1.93 — 3.12 2.21 1.50 12 20.066 1-isocyano-2-methyl-benzene 1.12 — 6.08 — — 2.28 13 23.105 5-methyl-indole 6.19 2.75 3.60 9.09 1.26 2.35 14 25.472 alanine 7.12 — — 5.91 — — 15 25.599 1,4-anhydrous-mannitol 3.12 — — — — 3.84 16 26.076 2-acrylic acid,3-methylamino-ester — 3.24 4.68 — — — 17 27.035 isopropyl-3-phenylpropanamide — 1.28 — 2.28 1.29 1.32 18 28.355 Syringol 7.21 — — 0.93 2.91 4.38 19 29.266 2,7-dimethyl-indolizine — — — 2.18 — — 20 30.191 N-dinitrophenyl-l-tryptophan — — — — — 2.96 21 32.682 6-ethyl-2,3-dimethyl pyridine — — — 3.99 — — 22 32.69 2triazine-3-keone — — — — 2.37 — 23 38.203 1,4-dionePyrrolo pyrazine — — — — — 2.87 24 38.29 2,5-dione,3,6-diisopropyl piperazin 2.12 5.45 3.27 5.42 3.76 1.72 25 39.089 1-methyl-indole 19.71 9.22 6.82 7.10 7.93 9.21 26 40.711 2,5-piperazinodione, 3,6-bis (2-methylpropyl- 9.32 — 9.61 4.88 3.52 3.46 27 41.719 1-methyl-indole — — — — 5.10 — 28 42.291 6-methyl-octadecane — — — — — 11.49 29 44.006 Deoxyspermidine guanidin — — 10.98 4.72 — — 30 44.239 1-heptyne-alcohol — — — — — 12.56 31 44.791 Cyclopentanone, oxime 6.06 13.29 11.77 13.08 21.76 16.54 32 45.724 9,12-octadecadienoic acid — — — — 13.08 — 33 45.755 linoleic acid 7.21 — — 9.40 — — 34 45.758 1-alcohol-tetradece 0.87 — 14.18 — — — 35 48.679 2-amino-imidazole 2.12 5.75 — 9.46 — — 36 48.731 1-octadecylamine 0.72 — — — 12.53 — 37 49.495 Cyclo-(1-leucyl-l-phenylalanyl) — 11.21 20.98 5.01 — — 38 50.581 1-alcohol-pentadecadiene 0.02 — — 4.05 14.89 3.51 表 7 兩均相催化劑不同投加量元素分析結果(質量分數)
Table 7. Element analysis results of different dosage of two homogeneous catalysts
% Catalyst Catalyst dosage C H N S O High heating value/
(MJ?kg?1)None 0 65.19 8.06 9.19 1.06 12.96 30.1290 Na2CO3 1 71.48 8.68 6.29 1.25 12.30 31.9690 3 72.28 8.66 7.07 1.29 10.71 32.3950 5 72.39 8.57 7.15 1.21 10.68 32.3390 8 73.64 8.38 6.83 1.23 9.93 32.6510 10 74.16 8.77 6.88 1.18 9.01 33.3220 NaOH 1 72.46 8.65 7.01 1.36 10.52 34.4750 3 72.22 8.72 7.19 1.31 10.57 34.4690 5 68.12 8.60 6.45 1.03 15.80 33.5620 8 70.75 8.86 6.11 0.89 13.39 34.4700 10 73.14 8.73 6.97 1.24 9.27 34.7320 www.77susu.com -
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