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Current Issue
2024 Vol.41 Issue.6,
Published 2024-11-15
0
2024 Vol. 41 (6): 0-0 [
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] (
235
) [
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1
Preparation of BiOBr/CN heterojunctions and analysis of the performance of photocatalytic reduction of CO
2
LIU Xuemei, LUO Xiuyu, WANG Hua
It is an important subject for the development of new and efficient photocatalysts for the photocatalytic reduction of CO
2
. In recent years, two-dimensional bismuth halide oxide has become a photocatalytic material of great interest due to its unique tunable layered structure and excellent photogenerated charge separation ability. In this study, based on the advantages of two-dimensional (2D) heterojunction catalysts with tunable band gap and short charge transfer distance, we aim to prepare size-matched BiOBr/CN 2D/2D heterojunction photocatalysts and investigate their photocatalytic CO
2
reduction performance. A series of BiOBr/CN composite photocatalysts were prepared by varying the amount of CN added. The morphology and structure of the BiOBr/CN composites were characterised by XRD, FTIR, SEM, TEM, HRTEM and XPS, and the successful preparation of the 2D/2D composites was confirmed. The results of the photocatalytic CO
2
reduction tests showed that all the BiOBr/CN composite photocatalysts exhibited enhanced photocatalytic activity compared to pure CN and BiOBr. Within 3 h of illumination, BiOBr/CN-0.15 showed the best photocatalytic activity with a CO evolution rate of 6.6 μmol·g
-1
·h
-1
, 3.8 and 16.0 times that of CN and BiOBr, respectively, and a CH
4
production rate of 0.7 μmol·g
-1
·h
-1
, three times that of CN. The results of band structure, PL spectra and electrochemical tests showed that a type II heterojunction was formed by combining BiOBr and CN, and the presence of the heterojunction promoted the separation and migration of photogenerated carriers, allowing more photogenerated electrons to reach the catalyst surface and participate in the CO
2
reduction reaction, thus significantly improving the performance of photocatalytic CO
2
reduction. This study is of great value for the design and application of BiOBr-based 2D/2D heterojunction photocatalysts.
2024 Vol. 41 (6): 1-11 [
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54
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12
Research progress on polyaniline modified photocatalysts
FENG Zhaoyu, GONG Yousheng, ZHENG Kaitian, JIAO Long, XU Chunjian
The environmental green photocatalytic technology is an effective way to solve the current energy problems and water pollution problems, however, there are still problems such as low photocatalytic efficiency and difficulty in application. In this paper, the basic photocatalytic process is described, and the modification of polyaniline (PANI) is shown to promote the light absorption, carrier separation and surface reaction of photocatalysts. On this basis, the synthesis of PANI-modified photocatalysts is introduced, and the applications of PANI-modified photocatalysts prepared by various methods for organic pollutant degradation, hydrogen production and heavy metal ion removal reported in the literature in recent years are sorted out. Finally, the current status and future development of PANI-modified photocatalysts are prospected.
2024 Vol. 41 (6): 12-25 [
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52
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107
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26
Optimization of synthesis of trimethylolpropane catalyzed by [Bmmim]OH by Box-Behnken method
SU Qiyi, XIE Tian, QUAN Hongdong, YANG Xiuguo, LI Hongyan
[Bmmim] OH was synthesized by reacting [Bmmim] Br and KOH in methanol for 24 h and purified with a yield of 87.39%. Trimethylolpropane was synthesized using the synthesized [Bmmim]OH as catalyst and formaldehyde and butanal as substrates. Based on the single factor experiments, the effects of Cannizzaro reaction time, molar ratio of HCHO to CH
3
CH
2
CH
2
CHO, and CH
3
CH
2
CH
2
CHO drop acceleration on the product concentration of trimethylolpropane were investigated. A Box-Behnken response surface method is used to establish a mathematical model by taking the product concentration of trimethylolpropane as the response value. The order of interaction among the three was: molar ratio of formaldehyde and butanal > CH
3
CH
2
CH
2
CHO drop acceleration > Cannizzaro reaction time. The optimal process conditions were as follows: the molar ratio of formaldehyde to butanal was 3.074, the Cannizzaro reaction time was 37.21 min, and the drop acceleration was 10.45 r·min
-1
. The deviation between the experimental value and the predicted value is 2.65%, indicating a good fit.
2024 Vol. 41 (6): 26-33 [
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54
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87
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34
Continuous-flow azo-coupling reaction of C.I. Pigment Red 146 with all inputs are solution
TONG Liyin, ZHOU Xueqin, XU Zhenxiang, LIU Dongzhi, LI Wei, CHEN Yong
The continuous synthetic process of azo pigments satisfies the national strategic needs of producing important basic materials in a green, low-carbon and efficient way. However, the blockage in the pipeline and reactor limits industrial production and application of continuous synthetic process. This work investigates the continuous-flow azo-coupling process of C.I. Pigment Red 146 to evaluate the feasibility of azo pigment continuous synthetic process with all inputs dissolved, in an attempt to tackling the blockage issue. Using polyethylene glycol (PEG) as a hydrotrope, the reagent N-(4-chloro-2,5-dimethoxyphenyl)-3-hydroxy-2-naphthalene amide (Naphthol AS-LC) in water exhibits as a clear solution. The continuous coupling reaction is conducted by addition of strongly acidic diazonium salt and strongly basic Naphthol AS-LC solution into a tubular colliding micromixer, which takes the advantage of faster acid-base neutralization than coupling reaction, so that the continuous coupling process of C.I. Pigment Red 146 can be achieved by the regulation of pH of the reaction mixture via the basicity of Naphthol AS-LC solution. The processing conditions, including pH of reactor outlet, volume fraction of PEG, input flow rate and post-treatment temperature were fully optimized. The azo-coupling reaction yield reaches up to 95.04% by setting the aforementioned parameters as pH=6, 10%, 60 L·h
-1
and 85 ℃, respectively. The color property (Δ
E
) of the products is less than 1 compared with standard sample, and the particle sizes are significantly smaller than those obtained by batch process. The continuous-flow azo-coupling reaction of C.I. Pigment Red 146 with all inputs dissolved promotes the yield of pigment, reduces energy consumption and more importantly, avoids the blockage, realizing efficient and safe azo-coupling reaction.
2024 Vol. 41 (6): 34-41 [
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84
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42
Preparing supported metallocene catalysts and applying in production of polyethylene with wide molecular weight distribution
GU Yongyao, WANG Lijuan, JIANG Tao, LI Jian
Metallocene polyethylene has superior properties, but its molecular weight distribution is usually narrow, which will bring a series of problems such as difficulties in subsequent molding and processing, and limit its large-scale application. In this study, a supported metallocene catalyst was obtained by using methylaluminoxane (MAO)-modified silica gel as a carrier and metallocene compound as the active component, and metallocene polyethylene was obtained by catalyzing ethylene polymerization in a slurry system. The effects of preparation conditions on loading and polymerization conditions on activity were systematically investigated, and the catalysts and polymerization products were analyzed and characterized by scanning electron microscopy, inductively coupled plasma mass spectrometry, laser particle size analyzer, and high-temperature gel permeation chromatography. The experimental results showed that the activity release of the supported catalyst was moderate, and the activity of the supported catalyst could reach 1 576.5 g·g
-1
. After the addition of 1-hexene, the processing properties of the product were improved, the melting point, density, bulk density and crystallinity of the polymer became lower, the molecular weight distribution was broadened from 2.6 to 3.2, and the melt flow rate increased from 0.088 2 to 0.36 g·min
-1
.
2024 Vol. 41 (6): 42-49 [
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93
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66
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50
Study on electrocatalytic reduction of CO
2
by long chain alkoxy modified nickel phthalocyanine
ZHANG Xinai, ZHANG Bo, LIU Xueling, GAO Ling, LI Jinchao, CHEN Liang, ZHANG Yaping
Developing and designing inexpensive, efficient, and low overpotential electrocatalytic CO
2
reduction (ECR) catalysts is crucial for alleviating greenhouse effect and transforming carbon dioxide into treasure. In this study, the nickel phthalocyanine based molecular dispersion catalysts (NiPc/CNT) were fabricated through modification by different long-chain alkoxy groups and immobilized onto multi-walled carbon nanotubes (MWCNTs). The successful synthesis of NiPc/CNT was confirmed through comprehensive structural characterization, including infrared spectroscopy (IR), Raman spectroscopy (Raman), UV-Vis spectroscopy (UV-Vis), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Experimental results demonstrate that the NiPc-6/CNT exhibits high catalytic activity and excellent selectivity for ECR within the potential range of -0.70 V to -0.95 V, and the Faraday efficiency for CO production (FE
CO
) approaches 100%. This study provides a novel molecular design strategy for the development of efficient electrochemical catalysts for ECR.
2024 Vol. 41 (6): 50-60 [
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99
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72
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61
Study on SCR-CO performance of Ce modified OMS-2 catalysts
CAI Chen, NING Shuying, CHEN Jiayin, FU Wei, ZHOU Hao, SU Yaxin
The Ce-modified OMS-2 catalysts (Ce
x
-OMS-2) were synthesized by one-step hydrothermal synthesis method, and its performance of selective catalytic reduction of NO by CO (SCR-CO) was evaluated in a fixed bed micro-reactor. The outcomes demonstrated that Ce
0.08
-OMS-2 achieved 100% NO conversion at 175—300 ℃ under the condition of 0.05%NO, 0.1%CO, 5%O
2
and N
2
as equilibrium gases, and the N
2
selectivity reached a maximum of 93.2% at 175 ℃. By using XRD, BET, XPS, NH
3
-TPD and H
2
-TPR to characterize the catalysts, the effects of doping the active metal Ce on the physicochemical characteristics of OMS-2 catalysts were investigated. The results demonstrate that the improvement of the low-temperature activity of the Ce
x
-OMS-2 catalyst is facilitated by lower agglomeration and crystallinity, larger specific surface area and pore volume, smaller average pore size, enhanced surface oxygen vacancies, increased Mn
4+
concentration, and more Brønsted acid.
2024 Vol. 41 (6): 61-69 [
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117
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3475KB] (
79
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70
Preparation and performance study of high temperature resistant fluid loss additive
CAO Chengzhang, CHANG Qinglu, HU Miaomiao, GUO Jintang
In order to improve the fluid loss performance of oil well cement at high temperature, a high temperature resistant fluid loss additive FLA-2 was synthesized by free radical copolymerization using 2-acrylamide-2-methylpropanesulfonic acid (AMPS), N, N-dimethylacrylamide (DMAA), itaconic acid (IA) and high temperature resistant cyclic monomer S as raw materials in the presence of initiator APS. The fluid loss additive FLA-1 was synthesized by AMPS, DMAA and IA as a comparison sample, and the performance of the fluid loss additive FLA-2 after adding the high temperature resistant monomer S was analyzed. The results showed that the water loss of cement containing FLA-2 was 22 mL in a salt water system with a salt mass fraction of 15%, which was significantly reduced by 21.4% compared with that of cement containing FLA-1.
2024 Vol. 41 (6): 70-74 [
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51
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44
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75
Research progress on the application of silicon-carbon anode materials in lithium-ion batteries
WANG Juan, ZHANG Xianglan
The structure and properties of anode materials are crucial for the capacity and performance of lithium-ion batteries. Silicon/carbon composites are highly regarded as promising anode materials for next-generation batteries due to their high specific capacity. However, the significant volume expansion during cycling hinders their commercialization. The structure and methods to synthesize silicon/carbon materials are key to addressing this issue. This paper provides an review of the lithium storage and failure mechanisms of silicon anodes, summarizes recent progress in silicon carbon anode materials for lithium-ion batteries, focuses on structural design and preparation methods, and assesses the future commercial prospects of silicon/carbon composites.
2024 Vol. 41 (6): 75-90 [
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52
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183
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91
Adsorption mechanism of MIL-101(Fe) for different complexed Cr(III)
QU Tingting, MA Hongrui, ZHANG Jing, HAO Yongyong, WANG Jiahong
Iron-based MOF materials have a good binding mechanism for complexed heavy metals due to their high number of unsaturated transition metal sites. Tannin (TA) has many differences in the adsorption behavior of heavy metals in the complexed formed with Cr(III) from small molecule complexes such as EDTA-Cr(III) due to the uncertainty in the molecular weight of its hydrolysis products. MIL-101(Fe) was selected as the adsorbent material and the TA-Cr(III) system was used as the mixed ligand complex to investigate the adsorption characteristics of TA-Cr(III) in water and to compare with the behavior of adsorbed EDTA-Cr(III). The results showed that the adsorption of MIL-101(Fe) for both organo-complexed Cr(III) belonged to the monolayer adsorption model. The adsorption amount of TA-Cr(III) was 277.79 mg·g
-1
under the same conditions, which was much larger than its adsorption amount of 120.48 mg·g
-1
for EDTA-Cr(III). The adsorption of MIL-101(Fe) on TA-Cr(III) was mainly due to the chelation of Fe(III) with —OH in tannic acid and its hydrolysis product gallic acid, whereas the adsorption on EDTA-Cr(III) was mainly due to the liganding effect of —COOH with Fe(III) and to a lesser extent to electrostatic interactions between the positive charges on the surface of the material and the (EDTACr)
-
.
2024 Vol. 41 (6): 91-100 [
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67
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81
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101
Experimental study on degradation of organic wastewater in dielectric barrier discharge microreactor
DING Yi, LIU Huiyang, YU Jianfeng, SUN Hui, WU Yongze
Organic wastewater poses a serious threat to the environment due to its difficult degradation. The existing methods of organic wastewater degradation have problems such as poor gas-liquid mixing effect and high discharge voltage. Therefore, a degradation device integrating microfluidic and dielectric barrier discharge was designed. Using methylene blue (MB) as a simulated pollutant, the effects of liquid flow rate, gas-liquid ratio, electrode area, barrier medium thickness and discharge voltage on MB degradation rate were investigated. The change of MB degradation rate under different degradation systems was compared and the contribution rate of ·OH was quantitatively analyzed. The experimental results showed that the degradation rate of MB was improved with the increase of the liquid flow rate and gas-liquid ratio in a certain range. With the increase of the electrode area and the discharge voltage, while the decrease of the thickness of barrier medium, all had positive effects on the degradation rate of MB. Under the conditions of a gas-liquid two-phase micro-discharge microbubble system, with an MB solution concentration of 0.04 mmol·L
-1
, a liquid flow rate of 3 mL·min
-1
, a gas-liquid ratio of 2.85∶1.00, an electrode area of 9 000 mm
2
, a discharge voltage of 9.5 kV, and a barrier medium thickness of 6 mm, a 15-minute cyclic operation, an MB degradation rate of 91.7% and an ·OH contribution rate of 68.9% were achieved, demonstrating superior degradation performance compared to other systems. This method can enhance the effect of gas-liquid mass transfer, promote the indirect oxidation reaction dominated by ·OH, and provide a feasible way for the degradation treatment of organic wastewater.
2024 Vol. 41 (6): 101-109 [
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49
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49
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110
Study on the adsorption performance of modified magnetic biochar on methylene blue
LI Wei, LI Yingjiao, LIN Chang, SONG Hui, XU Shuying
In this study, magnetic biochar was modified using (CH
3
COO)
2
Zn to prepare modified magnetic biochar MBC600. The magnetic biochar samples before and after modification was characterized and adsorption experiments were carried out on methylene blue (MB) in aqueous solution. The results showed that the specific surface area of (CH
3
COO)
2
Zn-modified magnetic biochar MBC600 was enhanced from 381.4 to 799.7 m
2
·g
-1
, the pore volume from 0.27 to 0.46 cm
3
·g
-1
, and the saturated magnetization intensity from 13.20 to 18.18 emu·g
-1
. The maximum adsorption of MB by MBC600 at 25 ℃ was 344.06 mg·g
-1
, which was 4 times higher than that of the unmodified. The kinetic and thermodynamic fitting of the adsorption of MBC600 revealed that the adsorption of MB by MBC600 was mainly a monomolecular adsorption under the control of chemisorption. MB adsorption is via hydrogen bonding and cation exchange.
2024 Vol. 41 (6): 110-119 [
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] (
84
) [
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5077KB] (
69
)
120
Preparation and desulfurization performance of coal gangue composite adsorption material
TIAN Yuhong, YANG Rongtian, ZHANG Lichao, LI Linbo
The preparation of composite adsorption materials from coal gangue can realize the high value resource utilization of coal gangue. With coal gangue as the base material and enteromorpha powder as the additional carbon source, the activated carbon porous silicon composite was prepared by one-step carbonization activation method. The structure of the composite was characterized by nitrogen adsorption, scanning electron microscopy (SEM), Fourier infrared spectroscopy (FTIR), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). The effects of activator concentration, activation temperature and activation time on the adsorption performance of the composite were studied. The results showed that the iodine adsorption performance and sulfur penetration capacity of the composite prepared under the conditions of 20% NaOH concentration, 800 ℃ and 60 min were 703 mg·g
-1
and 76.5 mg·g
-1
, respectively. The mesoporous pore size less than 10 nm accounted for 41.07%. It was found by FTIR and XRD that the amorphous silicon existed on the surface of the sample after the acid-leaching process, and the additional carbon source introduced by Enteromorpha enteromorpha formed the activated carbon porous silicon composite. It was found by EDS that the S element was uniformly distributed on the surface of the sample during the desulphurization process, and the final composite material had good adsorption desulphurization effect.
2024 Vol. 41 (6): 120-127 [
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] (
51
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42
)
128
Investigation on influencing factors of crystallization characteristics of phosphorus-based minerals in urine diversion system
YAN Zhengxu, CHEN Jing, YANG Zhen, CHENG Shikun, LI Zifu
The deposition of phosphorus-based minerals in urine diversion system has been one of the main challenges to establish large-scale urine diversion system. The crystallization characteristics of phosphorus-based minerals were systematically evaluated in this paper, and the effects of various factors such as pH, calcium-magnesium molar ratio, citrate, and rotational speed on the crystallization characteristics of phosphorus-based minerals were studied. The results indicated that the pH and the calcium-magnesium molar ratio were the main factors affecting the crystallization characteristics of phosphorus-based minerals in urine. The increase in the initial pH resulted in a decrease in the purity of struvite in the crystalline substance. When the initial pH increased from 7.0 to 8.0, the initial supersaturation index of HAP[Ca
10
(PO
4
)
6
(OH)
2
], OCP[Ca
4
H(PO
4
)
3
·3H
2
O(s)], ACP[Ca
3
(PO
4
)
2
] and TCP[Ca
3
(PO
4
)
2
] increased significantly, resulting in a rapid increase in the proportion of Ca-P compounds in the crystalline substance. The growth process of struvite crystals was influenced by Ca-P compounds, which resulted in the transformation of crystal morphology from regular polyhedral crystals to irregularly shaped crystals. And the crystal surface was covered by a large number of amorphous Ca-P compounds. Compared with calcium and magnesium ions, phosphate is "excessive" in urine. There was no obvious competition relationship between Ca-P compounds and Mg-P compounds. Calcium ions mainly affected the growth process of struvite crystals. With the increase of the initial calcium-magnesium molar ratio, the proportion of struvite crystals in the crystalline substance decreased, which was mainly due to the formation of more Ca-P compounds in the yellow water as the concentration of calcium ions increased.
2024 Vol. 41 (6): 128-135 [
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87
) [
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60
)
136
Preparation and property study of levofloxacin multi-component crystals
CHEN Wu, GU Zhendong, ZHENG Zhiyong, LIANG Xiaoxiao, LIU Shiyuan, JIANG Yanbin
Multi-component crystal is an effective way to improve the physicochemical and biochemical properties of drugs. Levofloxacin (LEV) is an antibacterial and anti-infective drug with high solubility and high antibacterial activity, but still exists some adverse effects. In this study, LEV was selected as the model drug, and partial least squares regression (PLS) models were used to predict the co-formers that might form multi-component crystals with levofloxacin. Guided by the prediction results, LEV multi-component crystals were prepared, then the stability and in vitro antibacterial activity of the samples were investigated. The results show that 7 of the 17 selected co-formers are successfully prepared as multi-component crystals with LEV, and 5 co-formers are successfully hit by the prediction results. Among the prediction models, the Hansen solubility parameter/COSMO-RS two-parameter prediction model has the highest accuracy, with an overall accuracy of 82.4% and a positive accuracy of 83.3% for the experimental systems, respectively. The stability of 5 multi-component crystal samples prepared is not significantly altered compared to the stable raw LEV, and the antibacterial activity against
E. coli
and
S. aureus
of all 7 prepared multi-component crystal samples is obviously improved. While achieving the same antibacterial activity as the raw LEV, it is expected that the prepared multi-component crystals would be effective in reducing the dose of the drug and reducing adverse effects.
2024 Vol. 41 (6): 136-148 [
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] (
51
) [
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5856KB] (
69
)
149
Interaction between thermodynamics and kinetics in trimorphic concomitant crystallization
LAN Jinqi, ZHU Zhenxing, XIE Chuang
Concomitant polymorphism is a special phenomenon of simultaneous crystallization of multiple polymorphs, which should be avoided in pharmaceutical process. The effects of thermodynamics-kinetics interaction on the trimorphic concomitant crystallization of sulfathiazole in water were discussed. The solubility of sulfathiazole Form II/III/IV in water at different temperatures was determined using dynamic method, indicating that Form III is a thermodynamically stable polymorph within 15—60 ℃, and Form II & IV have similar solubility. The nucleation induction period and corresponding polymorphs under different supersaturation were determined. It was found that pure Form III can be obtained at low supersaturation (1.15≤
S
≤1.40), while at high supersaturation (1.90≤
S
≤9.00) trimorphic concomitant crystallization occurs. Kinetics study shows that Form IV is the kinetically optimal polymorph, but Form II has the smallest critical radius and nucleation energy barriers. The interactions and competition of kinetic and thermodynamics can explain the above-mentioned supersaturation dependence of concomitant polymorphism. The Ostwald ratio was introduced to predict the ternary phase diagram of the concomitant crystallization of sulfathiazole in water, quantifying the effect of supersaturation on the ratio of the three concomitant polymorphs.
2024 Vol. 41 (6): 149-157 [
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] (
50
) [
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1KB] [
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68
)
158
Particle collision behavior and heat transfer performance in a gas-solid circulating fluidized bed heat exchanger with threaded tube
JIANG Feng, ZHU Lingyun, LEDUO Elizabeth Nawa, MOKHAMMAD Faridl Robitoh, LI Xiulun
Fluidized bed heat transfer and anti-fouling technology is applied to threaded tube heat exchanger. A heat exchange device of internal threaded circulating fluidized bed is designed and built to investigate the particle collision behavior and heat transfer performance under different operating parameters, such as air flow rate (12—20 m
3
·h
-1
), heat flux (1—3 kW·m
-2
), and particle type. Air and four types of particles are selected as working media. The results show that the heat transfer of threaded pipes can be enhanced by adding inert solid particles, but the system pressure drop is also increased. The maximum heat transfer enhancing factor can reach 27.2% with the addition of POM particles at
V
=16 m
3
·h
-1
and
q
=2 kW·m
-2
, and the maximum pressure drop ratio is no more than 38.5% within the experimental range. The characteristic frequency ranges of gas-phase and solid-phase collisions are 0—1 000 Hz and 5 000—2 5000 Hz, respectively. Particle collision plays a dominant role in the gas-solid two-phase flow collisions. As air flow rate increases, the signal power increases but the heat transfer enhancing factor first increases and then decreases. As heat flux increases, the heat transfer enhancing factor generally decreases. The effect of heat flux on signal power is relatively smaller compared with air flow rate. The heat transfer enhancing factor and signal power of GB particles are smaller than those of POM particles, and basically increase with the increase in GB particle size. With the increase in air flow rate or heat flux, the pressure drop ratio mainly shows an increasing trend, and decreases with the increase in GB particle size. The pressure drop ratio of POM particles is greater than that of GB3 particles.
2024 Vol. 41 (6): 158-168 [
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] (
60
) [
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1KB] [
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7038KB] (
61
)
169
Gaussian process regression modeling and prediction of temperature distribution in continuous tubular crystallizer
LI Yuanjun, ZHAO Mingyan, SONG Bo, LIU Tao
For the newly developed tubular continuous crystallizer and production process, this paper proposes a modeling method for the temperature profile of the tubular crystallizer based on Gaussian Process Regression (GPR). By measuring the temperatures in four sections of the DN15 tubular crystallizer, temperature profile models for each section are constructed based on GPR. Moreover, prediction models are established for the temperature distribution of continuous crystallization sections under different jacket flow rate operating conditions. Meanwhile, the northern goshawk optimization algorithm is adopted to determine the hyperparameters of these models, aiming to improve the prediction accuracy. Through experimental tests on the temperature distribution of each section during the
L
-glutamic acid continuous crystallization process under different jacket flow rates, the effectiveness and advantages of the proposed method are verified.
2024 Vol. 41 (6): 169-175 [
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] (
53
) [
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2868KB] (
68
)
176
Research on computational fluid dynamics for simulation of crystallization
GAO Yuan, HUA Yuxiang, ZHANG Jing
The crystallization process is an important process in many industrial and scientific applications. However, there are complex mass transfer, heat transfer, and fluid dynamics problems in crystallization process. It’s difficult for traditional experimental methods to grasp all the details of the crystallization process, which directly affects the performance and quality of products. Crystallization process simulation based on computational fluid dynamics (CFD) can be used to predict and analyze crystallization process and crystal product quality. Moreover, some quantitative models of crystallization kinetics can be also used in the crystallization process design, crystallization method development, scale-up of crystallizer and other fields. Thus, this article focuses on several numerical solutions of particle balance equations, and provides a detailed introduction of CFD-PBE simulation. The practical applications of this couple solving method in anti-solvent crystallization process, reactive crystallization process and crystallizer design process were also discussed. Finally, the research trends and development directions of CFD-PBE in industrial crystallization are prospected.
2024 Vol. 41 (6): 176-186 [
Abstract
] (
54
) [
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1KB] [
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2458KB] (
94
)
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