KEY ENGINEERING MATERIALS
·
2016
·
IF 0
Mi Mi Chen,Meng Meng Zhang,Feng Qing Zhao
A clean and safe process of utilizing waste penicillin mycelium (WPM) was proposed in this paper. We treated WPM by soaking it in aqueous alkaline solution, to produce retarders for hemihydrate gypsum (the protein hydrolysate) by filtration. The filter cake was used to produce activated carbon, while the waste water can be reused for soaking process. This retarder can effectively prolong the setting time of gypsum with less drop in mechanical strength of gypsum plaster. The activated carbon produced with 674 mg/g of Iodine value, which meets the requirements of general industrial applications.
研究领域:
生物工程
·
材料科学
·
环境科学
✓ 已验证
DOI
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Lei Zuo,Junfeng Wang,Deqing Mei,Derick Adu-Mensah,Yaping Gao
The amounts of methyl stearate (C18:0) and trans-methyl oleate (trans-C18:1) increase during the catalytic transfer hydrogenation (CTH) process of biodiesel. Although it could improve the oxidation stability of biodiesel, its low temperature performance would be worsened. As for it, ultrasonic was introduced in the CTH to control the generation of C18:0 and trans-C18:1. In this study, the ultrasonic-assisted CTH was performed using Raney-Ni as catalyst, isopropanol as hydrogen donor and water as solvent. The effect of operating parameters such as reaction temperature, stirring rate, catalyst dosage, isopropanol amount and water amount on hydrogenation process was investigated. It was revealed that the optimum reaction conditions were determined as reaction temperature 80 °C, stirring rate 600 rpm, catalyst dosage 10 wt%, isopropanol amount 32 g and water amount 100 g in the aspect of the iodine value of bioidesel and the yield of C18:0 and trans-C18:1. The process of the ultrasonic-assisted CTH for biodiesel could be well described by pseudo-first order kinetic model. The conversion rate constants from C18:2 to C18:1 ( k 1 ) and from C18:1 to C18:0 ( k 2 ) were 0.02649 min −1 and 0.00438 min −1 , respectively. Ultrasonic field effectively repressed the selectivity of trans-C18:1 and further decreased the iodine value of biodiesel. On the basis of the same iodine value, the yield of C18:0 and hydrogenation time reduced with ultrasonic. Overall, ultrasonic is an effective intensification method for the CTH of biodiesel in the aspect of product selectivity and reaction rate.
研究领域:
化学工程
·
可再生能源
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Yundi Huang,Fashe Li,Guirong Bao,Qingtai Xiao,Hua Wang
Biodiesel is a promising renewable energy the use of which facilitates the goals of carbon neutrality and timely carbon peak. The iodine value (IV), one of the major properties of biodiesel , denotes the degree of unsaturation and correlates with the chemical composition of biodiesel. In this work, a novel approach based on random forest (RF) and least squares support vector machine (LSSVM) algorithms optimized by whale optimization algorithm (WOA) is proposed for estimating the IV of biodiesel as a function of fatty acid methyl ester profiles. In doing so, the compositions and IVs of 52 biodiesel/binary biodiesel blends were determined by gas chromatography mass spectrometry and EN14111 standard. Then, LSSVM algorithm was assessed as the most appropriate predictive method compared to the adaptive neuro fuzzy inference system, multi-layer perceptron neural network, and decision tree algorithms. Continuously, four feature selection approaches (Pearson’s correlation coefficient, principal component analysis, ReliefF algorithm, and RF) were utilized to choose the most influencing fatty acid methyl ester combination as input. The RF-LSSVM model was found to be superior to other Ⅰ hybrid models. Then, WOA was incorporated into the modeling process and the RF-WOA-LSSVM model achieved a high performance with a root mean square error and correlation coefficient of 1.1893 and 0.9977, respectively. The accuracy and error of the RF-WOA-LSSVM model have been validated. Comparison with previous biodiesel IV machine learning models and application of other new experimental datasets from the literature prove the feasibility of the proposed hybrid RF-WOA-LSSVM model for estimating the IV of different biodiesels types.
研究领域:
能源科学
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机器学习
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2021
·
IF 5.645
Ru Zhao,Mengxia Wei,Guangyu Shi,Xun Wang,Hongfei Gao,Lin Zhang,Lei Yang,Huiyan Gu
In the present study, microwave-assisted biphasic extraction (MABE) was first and successfully applied to the simultaneous extraction of oil and sinigrin from field pennycress ( Thlaspi arvense ) through a one-pot process. Four potentially influencing factors on the yields of oil and sinigrin, including the ratio of lower phase to solid, ratio of upper phase to solid, microwave irradiation power, and microwave irradiation time, were selected for further optimization by Box–Behnken design, and the optimal extraction conditions were obtained as follows: ratio of lower phase to solid of 21 mL/g, ratio of upper phase to solid of 12 mL/g, microwave irradiation power of 389 W, and microwave irradiation time of 33 min. Under the optimal extraction conditions, the yields of oil (23.46 % ± 0.78 %) and sinigrin (18.42 ± 0.35 mg/g) from T. arvense seeds were maximized. The GC–MS analysis illustrated that the T. arvense seed oil obtained by MABE using n -hexane and water biphasic solvents and Soxhlet extraction using n -hexane solvent exhibited a similar fatty acid composition. The seed oil acquired by the efficient MABE demonstrated a higher quality due to its lower acid value and higher iodine value. Scanning electron microscopy results showed that the cell structure of seed tissues was obviously disrupted compared with untreated raw material and that treated by the conventional extraction method. In general, the results indicated that the proposed MABE is an efficient method for the extraction of oil and sinigrin from T. arvense seeds.
研究领域:
化学工程
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分析化学
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植物科学
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食品科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ANALYTICAL CHEMISTRY
·
2024
·Vol. 79
·期 2
·233-240
·
IF 1
Wai Phyu Thin,Jiang Pingping,Lu Minjia,Cui Zhixuan,Feng Shan,Zhang Pingbo
High-resolution 1 H nuclear magnetic resonance ( 1 H NMR ) was advanced to determine both epoxy value and iodine value ( IV ) of vegetable oils that occur during their epoxidation. For calibration, rather than using a series of diluted stock samples, epoxidized soybean oils with a range of IV and epoxy value synthesized using entrapped peroxophosphotungstate as the catalyst under different reaction conditions were used. During the epoxidation reaction, IV and epoxy value were tracked with respect to time using 1 H NMR and conventional volumetric methods. The integrated peak area of the olefinic hydrogens (5.3–5.5 ppm) was used to calculate the absolute number of double-bonded protons. By comparison of IV obtained by 1 H NMR and the traditional Wijs-cyclohexane methods, the correlation coefficient was R 2 = 0.9997 for the regression equation y = 1.1314 x + 1.0035, where x was the result given by 1 H NMR. The average integrated peak areas related to the hydrogens of the epoxide groups located at chemical shifts of 2.9 ppm (monoepoxide) and 3.1 ppm (diepoxide) were used to determine the epoxy value. The quantification of the number of epoxides was carried out by 1 H NMR and the values obtained were correlated with epoxide content determined by the hydrochloric acid/acetone method. As a consequence, the correlation coefficient was R 2 = 0.9991 for the regression equation y = 0.0052 x + 1.7258, where x was the average integrated peak areas related to the hydrogens of the epoxide groups by 1 H NMR. The novelty of our study lies in the simultaneous correlation between IV and epoxy value obtained from conventional titrations, the integrated peak area related to olefinic protons, and the average integrated peak area located at the hydrogen of epoxide group, calculated using 1 H NMR. This approach is used to monitor and optimize the epoxidation reaction.
研究领域:
分析化学
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高分子科学
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有机化学
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光谱学
·
化学反应工程
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2021
·Vol. 29
·期 2
·2432-2447
·
IF 4.223
Huang Yundi,Li Fashe,Bao Guirong,Li Meng,Wang Hua
Iodine value (IV) is an indicator to evaluate the degree of unsaturation (DU) of biodiesel. It reflects the biodiesel degradation and oxidation stability (OS) and also has an effect on viscosity, low-temperature flow properties (LTFP), and the combustion performance. To construct a theoretical system for the simultaneous optimization of LTFP and OS of biodiesel using IV, 52 measured experimental data are used to investigate the qualitative and quantitative relationship between IV and biodiesel composition. The relationships between biodiesel physicochemical properties and IV are investigated in this work. The qualitative analysis shows that the poly-unsaturated fatty acid methyl esters (FAMEs) contribute to an increase in IV, whereas saturated and mono-unsaturated FAMEs decrease IV. Multiple linear regression (MLR) and artificial neural network (ANN) are used to estimate IV from FAMEs. The correlation coefficient, root mean squared error (RMSE), and mean absolute percentage error (MAPE) are respectively 0.976, 2.45, and 1.76% for the MLR model and 0.983, 2.14, and 1.57% for the back propagation neural network (BPNN) model; these values indicate the high accuracy of these methods. The performances of the proposed models were compared with three existing IV prediction models and validated by another databank. The results indicate that the application of the developed BPNN model is better and more comprehensive. Additionally, a preliminary conclusion is that biodiesel with a low percentage of both long-chain saturated and poly-unsaturated FAMEs can have solidifying point (SP) and OS in the proper range. Biodiesel with a low IV is generally more combustible and efficient.
研究领域:
化学工程
·
可再生能源
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）