South African Journal of Chemical Engineering最新文献_第6页

Computational modeling of peristaltic blood flow in a tapered channel with radiative heat flux and reaction mechanisms 具有辐射热通量和反应机制的锥形通道中蠕动血流的计算模型

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-11-10 DOI: 10.1016/j.sajce.2025.11.005

S. Ravikumar , Ali B.M. Ali , Raghunath Kodi , Ghulam Rasool , Umid Turdialiyev , Dilsora Abduvalieva , M.Ijaz Khan , Nidhal Ben Khedher

The article demonstrates how computational methods help scientists study peristaltic blood flow and heat transport within biomedical systems. The present model uses peristaltic wave theory to build its framework while incorporating nonuniform boundary conditions. The channel walls show significant concurrence that matches real-world convective conditions. The established conditions enable researchers to study particle movement behavior which becomes essential for cardiac surgery applications. The mathematical model equations underwent transformation through lubrication techniques produced analytical solutions. The accuracy of present findings becomes evident through direct comparison with previously documented research results in scientific literature. The results match each other to a high degree. The hartmann number increase leads to an enhancement of fluid velocity according to this study. The hartmann number adjustment through external magnetic fields enables practical blood flow management which enhances medical device performance and drug delivery system accuracy. The Prandtl number decreases fluid velocity because viscous forces start to dominate thermal diffusivity. The relationship between these two parameters affects multiple fluid systems including blood flow in human bodies and various physical and biological systems. The heat transfer efficiency between conduction and convection increases when the heat biot number reaches higher values. The improved energy transfer leads to increased fluid velocity. The temperature profile shows significant changes because of thermal radiation effects. Medical biology depends on this parameter to optimize treatments through hyperthermia and study thermoregulation and create diagnostic and therapeutic equipment. The chemical reaction parameter strongly affects the concentration levels of the fluid. The knowledge of this relationship enables scientists to create improved therapeutic methods and enhance drug delivery systems and tissue engineering approaches. The chosen qualities are applicable in medical biology, biomechanics, heat exchangers, gas turbines, and several other fields.

这篇文章展示了计算方法如何帮助科学家研究生物医学系统中的蠕动血液流动和热量传输。该模型采用蠕动波理论构建框架，同时考虑了非均匀边界条件。通道壁显示出与真实对流条件相匹配的显著并发性。所建立的条件使研究人员能够研究粒子的运动行为，这对心脏外科应用至关重要。通过润滑技术对数学模型方程进行变换，得到解析解。通过与科学文献中先前记录的研究结果的直接比较，本研究结果的准确性变得明显。结果非常吻合。根据本研究，哈特曼数的增加导致流体速度的增强。通过外部磁场的哈特曼数调整实现了实际的血流管理，从而提高了医疗设备的性能和给药系统的准确性。普朗特数降低流体速度，因为粘性力开始支配热扩散。这两个参数之间的关系影响着包括人体血流在内的多个流体系统以及各种物理和生物系统。热传导与对流的换热效率随着热biot数的增大而增大。能量传递的改善导致流体速度的增加。由于热辐射的影响，温度分布有明显的变化。医学生物学依靠该参数通过热疗优化治疗，研究体温调节和创建诊断和治疗设备。化学反应参数强烈地影响流体的浓度水平。这种关系的知识使科学家能够创造改进的治疗方法，增强药物输送系统和组织工程方法。所选的品质适用于医学生物学、生物力学、热交换器、燃气轮机和其他几个领域。

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引用次数: 0

Crystallographic insights into copper oxide nanoparticles synthesized via a unique sol-gel method: Antibacterial activity and photocatalytic evaluation 通过独特的溶胶-凝胶法合成的氧化铜纳米颗粒的晶体学见解：抗菌活性和光催化评价

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-11-10 DOI: 10.1016/j.sajce.2025.11.006

Md. Khalid Hossain Shishir , Md. Ashraful Alam , Raton Kumar Bishwas , Mohammad Minnatul Karim , S.M. Nur Alam , Gazi Md. Arifuzzaman Khan

A unique sol-gel method was employed to synthesize high-purity copper oxide nanoparticles (CuO NPs) using starch as a natural stabilizer and citric acid as a gelling agent, enabling precise control over nucleation, growth and structural integrity. The synthesized CuO NPs were analyzed utilizing various techniques, including X-ray diffraction (XRD), Fourier Transform Infrared (FTIR), UV–Vis spectroscopy, Dynamic Light Scattering, Zeta potential, Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray spectroscopy. XRD analysis validated monoclinic crystal structure with average crystallite size of 21.72 nm and 100 % CuO purity, while SEM revealed uniformly spherical particles. FTIR spectroscopy showed distinct absorption bands at 598.49 cm⁻¹ and 532.83 cm⁻¹ for Cu–O stretching and UV–Vis analysis indicated an absorption peak at 392.08 nm with a 2.01 eV band gap, suggesting sunlight-driven photocatalytic potential. The measured zeta potential of +27.92 mV indicates moderate colloidal stability. The CuO NPs exhibited antibacterial activity against Staphylococcus aureus while no inhibitory effect was observed against multi-drug resistant Escherichia coli. The photocatalytic performance was evaluated through sunlight-assisted degradation of methylene blue, achieving an efficiency of about 88 % within 210 min. This study aims to synthesize high-purity, well-dispersed CuO NPs for precise control over structure and stability. The work’s impact lies in showcasing bio-assisted CuO NPs as efficient sunlight-driven photocatalysts and effective antibacterial agents, highlighting their promise for sustainable environmental and biomedical applications.

以淀粉为天然稳定剂，柠檬酸为胶凝剂，采用独特的溶胶-凝胶法合成了高纯氧化铜纳米颗粒（CuO NPs），实现了对成核、生长和结构完整性的精确控制。利用x射线衍射（XRD）、傅里叶变换红外（FTIR）、紫外可见光谱（UV-Vis）、动态光散射、Zeta电位、扫描电子显微镜（SEM）和能量色散x射线光谱等技术对合成的CuO NPs进行了分析。XRD分析证实了单斜晶的结构，平均晶粒尺寸为21.72 nm， CuO纯度为100%，SEM显示为均匀的球形颗粒。FTIR光谱显示Cu-O在598.49 cm -⁻¹和532.83 cm -⁻¹处有明显的吸收谱带，UV-Vis分析显示吸收谱峰在392.08 nm处，带隙为2.01 eV，表明有阳光驱动的光催化潜力。zeta电位为+27.92 mV，胶体稳定性中等。CuO NPs对金黄色葡萄球菌具有抑菌活性，对多重耐药大肠杆菌无抑制作用。光催化性能通过日光辅助降解亚甲基蓝来评估，在210分钟内达到约88%的效率。本研究旨在合成高纯度、分散良好的氧化铜纳米粒子，以精确控制其结构和稳定性。这项工作的影响在于展示了生物辅助的CuO NPs作为高效的阳光驱动光催化剂和有效的抗菌剂，突出了它们在可持续环境和生物医学应用方面的前景。

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引用次数: 0

Physicochemical properties of banana leaves at different growth stages: Effects of bleaching and natural dyeing with lac, butterfly pea, and turmeric 香蕉叶在不同生长阶段的理化性质：紫胶、蝶豆和姜黄对漂白和天然染色的影响

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-11-09 DOI: 10.1016/j.sajce.2025.11.004

Sopida Wisansakkul , Orawan Oupathumpanont

This research aimed to study the impact of bleaching and natural dyeing on the physicochemical properties of banana leaves at various stages of growth. Banana leaves were bleached and dyed using three natural dyes: lac, butterfly pea, and turmeric. The bleaching process reduced the moisture content from 66.05 % to 11.98 %–15.50 % and decreased the thickness and opacity of the leaves, while glossiness was not significantly affected. EDS analysis identified carbon, oxygen, silicon, phosphorus, and potassium as the five main elements present after bleaching. The color values of the leaves changed noticeably; the a* value shifted toward red, and the b* value toward yellow. Six-month-old banana leaves were found to be most suitable for dyeing due to their structure and dye absorption properties. When dyed, lac produced a dark red tone (L* = 61.14, a* = 3.95, b* = -2.90), and butterfly pea yielded a blue-green shade (L* = 62.40, a* = -1.00, b* = -4.60), and turmeric resulted in an orange-yellow hue (L* = 68.41, a* = 8.79, b* = 7.19). These findings suggest the potential of using naturally dyed banana leaves as sustainable, biodegradable materials for creative product design, particularly in eco-friendly fashion and lifestyle items such as handbags and backpacks.

本研究旨在研究漂白和自然染色对香蕉叶不同生长阶段理化性质的影响。香蕉叶用三种天然染料：紫胶、蝶豆和姜黄进行漂白和染色。漂白处理使叶片含水量从66.05%降低到11.98% ~ 15.50%，叶片厚度和不透明度降低，光泽度无显著影响。能谱分析确定了碳、氧、硅、磷和钾是漂白后存在的五种主要元素。叶片的颜色值变化明显；a*值向红色移动，b*值向黄色移动。六个月大的香蕉叶因其结构和染料吸收特性而最适合染色。当染色时，紫胶产生深红色色调（L* = 61.14, a* = 3.95, b* = -2.90），蝶豆产生蓝绿色色调（L* = 62.40, a* = -1.00, b* = -4.60），姜黄产生橙黄色色调（L* = 68.41, a* = 8.79, b* = 7.19）。这些发现表明，将天然染色的香蕉叶作为可持续的、可生物降解的材料用于创意产品设计，特别是在手提包和背包等环保时尚和生活方式用品方面的潜力。

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引用次数: 0

Green synthesis of bimetal Mg-Y doped ZnO nanorods using extract of Sargassum siliquosum and their potential as biomedical materials 马尾藻硅藻土提取物绿色合成双金属Mg-Y掺杂ZnO纳米棒及其生物医用材料潜力

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-11-08 DOI: 10.1016/j.sajce.2025.11.003

Yetria Rilda , Wilna Putri Akmalya , Upita Septiani , Syukri Syukri , Anthoni Agustien , Hilfi Pardi , Nofrijon Sofyan

The macroalga Sargassum siliquosum contains amino-cellulose bioactive compounds that act as stabilizing agents and growth controllers for metal precursor ions in the synthesis of Mg-Y/ZnO nanorods. This study aims to improve the multifunctional biomedical performance of ZnO (antibacterial, antioxidant, anti-inflammatory, and antidiabetic) through bimetal ion doping using Magnesium (Mg²⁺, 0.71 Å) and Yttrium (Y³⁺, 1.05 Å) at concentration ratios of 0.01–0.03 M within the ZnO lattice. Thermal analysis (TGA/DTA) shows that Mg-Y doping reduces the thermal stabilization temperature of ZnO from 800°C to 600°C. X-ray diffraction confirms the formation of a hexagonal wurtzite structure without secondary phases, supported by Rietveld refinement, FT-IR bonding profiles, and UV-Vis (Tauc plot) band gap narrowing to 3.01–3.10 eV. FE-SEM images reveal nanorod morphology of 25–35 µm, while EDX verifies Mg and Y incorporation. The doped samples exhibit strong antibacterial activity, with inhibition zones of ≥ 20 mm against Staphylococcus aureus and Pseudomonas aeruginosa. The 0.03 M Mg-Y/ZnO sample exhibits the highest biomedical performance, with significant antioxidant (IC₅₀ = 71.6 mg/L), anti-inflammatory (368 mg/L), and antidiabetic (420 mg/L) activities. These results indicate that Mg-Y bimetal doping enhances ZnO functionality and offers promising potential as a multifunctional biomedical material.

硅藻含有氨基纤维素生物活性化合物，在Mg-Y/ZnO纳米棒的合成中作为金属前体离子的稳定剂和生长调节剂。本研究旨在通过在ZnO晶格内以0.01-0.03 M的浓度比掺杂镁（Mg2+, 0.71 Å）和钇（Y3+, 1.05 Å）的双金属离子，提高ZnO的多功能生物医学性能（抗菌、抗氧化、抗炎和降糖）。热分析（TGA/DTA）表明，Mg-Y掺杂使ZnO的热稳定温度从800℃降低到600℃。x射线衍射证实了无二次相的六方纤锌矿结构的形成，Rietveld细化、FT-IR键合谱和UV-Vis （Tauc图）带隙缩小至3.1 - 3.10 eV。FE-SEM图像显示纳米棒形貌为25-35µm，而EDX则证实了Mg和Y的掺入。该掺杂样品具有较强的抗菌活性，对金黄色葡萄球菌和铜绿假单胞菌具有≥20 mm的抑制区。0.03 M mg - y /ZnO样品表现出最高的生物医学性能，具有显着的抗氧化（IC₅0 = 71.6 mg/L），抗炎（368 mg/L）和抗糖尿病（420 mg/L）活性。这些结果表明，Mg-Y双金属掺杂增强了ZnO的功能，作为一种多功能生物医学材料具有很大的潜力。

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引用次数: 0

Effects of gallery-walk in process simulation course 廊道行走在工艺模拟过程中的作用

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-11-05 DOI: 10.1016/j.sajce.2025.11.002

A. Anantpinijwatna

This study examines the integration of the gallery-walk active learning strategy into a third-year Process Simulation course. Using a quasi-experimental design, student performance was compared across two traditional lecture cohorts (n = 157) and two gallery-walk cohorts (n = 158). Direct analysis revealed the gallery-walk was associated with improved performance on simple simulation problems, with the average percentage of correct answers rising from 63 % to 70 %. However, a performance decline on complex problems was observed in the initial implementation; this was mitigated in the second iteration by adding an instructor-led summarization phase. Notably, the intervention did not increase the number of top-performing students (scores >90 %), a finding potentially explained by the expertise reversal effect. Anonymous surveys indicated a significant increase in student satisfaction and engagement. This study demonstrates the gallery-walk's potential in engineering education but underscores the necessity of iterative refinement to address complex problem-solving and support learners at all proficiency levels.

本研究考察了将画廊漫步主动学习策略整合到三年级过程模拟课程中的情况。采用准实验设计，比较了两个传统讲座队列（n = 157）和两个画廊步行队列（n = 158）的学生表现。直接分析表明，在走廊散步与简单模拟问题的表现改善有关，平均正确答案的百分比从63%上升到70%。然而，在最初的执行中，观察到复杂问题的性能下降；在第二次迭代中，通过添加一个由讲师指导的总结阶段，这一问题得到了缓解。值得注意的是，干预并没有增加表现最好的学生的数量（得分>； 90%），这一发现可能被专业逆转效应解释。匿名调查显示，学生的满意度和参与度显著提高。这项研究证明了画廊步行在工程教育中的潜力，但强调了迭代改进的必要性，以解决复杂的问题，并支持所有熟练程度的学习者。

引用次数: 0

Effect of hydrocyclone size on microplastics separation: a computational fluid dynamics investigation 水力旋流器粒径对微塑料分离的影响：计算流体动力学研究

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-11-02 DOI: 10.1016/j.sajce.2025.11.001

Dulyapat Thiemsakul , Shibo Kuang , Wiwittawin Sukmas , Eakarach Bumrungthaichaichan , Krittin Korkerd , Ratchanon Piemjaiswang , Pornpote Piumsomboon , Benjapon Chalermsinsuwan

Microplastics pose a significant environmental threat, particularly to aquatic ecosystems. Removing microplastics from water is a critical challenge due to their small size and widespread presence. In this study, the separation of polystyrene (PS) and polyethylene terephthalate (PET) microplastics in hydrocyclones was investigated using Computational Fluid Dynamics (CFD) simulations. A three-dimensional Eulerian-Eulerian multiphase model was employed to simulate the separation process, with water, air, and microplastics. The model demonstrated good agreement results, confirming the reliability of the simulation results. Two factors affecting hydrocyclone performance were investigated. The base hydrocyclone model was scaled down using factors ranging from 1.0 to 0.2 to investigate how size reduction influenced separation efficiency. The results showed that smaller hydrocyclones enhanced recovery (PS: 5.88 to 7.64%; PET: 7.79 to 14.86%) due to stronger centrifugal forces, while higher inlet velocities improved recovery but increased the pressure drop from 49 to 59 kPa, indicating a clear trade-off between separation efficiency and energy consumption. This increase was attributed to the higher centrifugal forces generated in smaller hydrocyclones, which more effectively pushed particles toward the walls, enhancing separation based on density. In addition, higher inlet velocities improved microplastic recovery by amplifying the centrifugal forces within the hydrocyclone, but this came at the cost of increased pressure drop and energy losses due to intensified turbulence and friction.

微塑料对环境构成重大威胁，特别是对水生生态系统。由于微塑料体积小且广泛存在，从水中去除微塑料是一项关键挑战。利用计算流体动力学（CFD）模拟研究了聚苯乙烯（PS）和聚对苯二甲酸乙二醇酯（PET）微塑料在水力旋流器中的分离。采用三维欧拉-欧拉多相模型模拟了水、空气和微塑料的分离过程。仿真结果吻合较好，验证了仿真结果的可靠性。研究了影响水力旋流器性能的两个因素。采用1.0 ~ 0.2的因子对基础水力旋流器模型进行缩小，考察粒径减小对分离效率的影响。结果表明，较小的水力旋流器由于离心力更强而提高了回收率（PS: 5.88 ~ 7.64%; PET: 7.79 ~ 14.86%），而较高的进口速度提高了回收率，但使压降从49 kPa增加到59 kPa，这表明分离效率和能耗之间存在明显的权衡。这一增长归因于较小的水力旋流器产生的更高的离心力，它更有效地将颗粒推向壁面，增强了基于密度的分离。此外，较高的进口速度通过放大水力旋流器内的离心力来提高微塑性回收率，但这是以增加的压降和因湍流和摩擦加剧而造成的能量损失为代价的。

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引用次数: 0

Influence of carbon sources and biosurfactants on selenite and lead bioremediation by Enterococcus sp 碳源和生物表面活性剂对肠球菌修复亚硒酸盐和铅的影响

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-30 DOI: 10.1016/j.sajce.2025.10.008

Job T. Tendenedzai, Evans M.N. Chirwa, Hendrik G. Brink

This study explored Enterococcus sp.'s potential for bioremediating selenite (SeO₃²⁻) and lead (Pb²⁺) contamination using different carbon sources (glucose, cooking oil and crude oil) while elucidating the underlying mechanisms. Aerobic batch reduction experiments were conducted (35±2 °C, 120 rpm, pH≈8, 50 h) with an initial 1 mM concentration of either SeO₃²⁻or Pb²⁺ which was quantified by Ion Chromatography and Atomic Absorption Spectroscopy respectively. Key results showed that carbon source selection significantly influenced SeO₃²⁻and Pb²⁺ removal rates, elemental selenium (Se⁰) formation, and protein synthesis. Glucose and cooking oil were found to be the most efficient, leading to rapid SeO₃²⁻reduction (58 % and 55 % reduction, respectively), compared to crude oil (39 %). Similarly, Pb²⁺ removal rates followed a similar trend, with 38 %, 33 %, and 25 % reduction using glucose, cooking oil, and crude oil, respectively. The study also highlighted Enterococcus sp.'s varied mechanisms for SeO₃²⁻and Pb²⁺ reduction, with SeO₃²⁻ precipitating to Se⁰ while no precipitation of Pb²⁺ to Pb⁰ was observed. Furthermore, the bacteria exhibited versatility in biosurfactant production across the various carbon substrates. The biosurfactants notably promoted Se⁰ precipitation thus shedding light on their potential role in metal ion bioreduction.

本研究探讨了肠球菌利用不同碳源（葡萄糖、食用油和原油）对亚硒酸盐（SeO32−）和铅（Pb2+）污染进行生物修复的潜力，并阐明了其潜在机制。在35±2℃，120 rpm, pH≈8,50 h的条件下，采用离子色谱法和原子吸收光谱法分别对初始浓度为1 mM的SeO32−或Pb2+进行好氧批量还原实验。关键结果表明，碳源选择显著影响SeO32−和Pb2+去除率、元素硒（Se0）形成和蛋白质合成。葡萄糖和食用油被发现是最有效的，导致SeO32−的快速还原（分别减少58%和55%），而原油（39%）。同样，Pb2+的去除率也有类似的趋势，葡萄糖、食用油和原油的去除率分别为38%、33%和25%。研究还强调了Enterococcus sp.还原SeO32−和Pb2+的不同机制，其中SeO32−沉淀为Se0，而Pb2+没有沉淀为Pb0。此外，该细菌在各种碳底物上表现出生物表面活性剂生产的多功能性。这些生物表面活性剂显著促进了Se0的沉淀，从而揭示了它们在金属离子生物还原中的潜在作用。

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引用次数: 0

Effect of gypsum addition on syngas production during CO2-assisted gasification of pinewood 石膏对松木co2辅助气化合成气产量的影响

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-30 DOI: 10.1016/j.sajce.2025.10.009

Athi-enkosi Mavukwana , Kiran Burra , Ashwani Gupta

This study investigates the potential synergistic effects of incorporating gypsum in CO₂-assisted gasification of pinewood. The synergistic interaction between pinewood and gypsum enhanced the efficiency of pinewood conversion into syngas, while simultaneously facilitating the conversion of gypsum into chemically valuable substances, such as calcium sulfide. During gasification, pinewood generated substantial quantities of tars and unreactive char. Tars, being compounds of considerable stability, present a significant obstacle in terms of achieving high conversion efficiency. The presence of gypsum increased the syngas yield from the conversion of char and tars. The results presented here empirically examined the impact of varying quantities of gypsum on the production of hydrogen (H₂) and syngas during its CO₂-assisted gasification with pinewood. The overall yield of syngas increased by up to 11.7 % while the LHV improved by 12.5 % using 16.67 wt.% of gypsum in pinewood. However, increased mass fractions of gypsum to 50 wt.% negatively affected the syngas production and reduced the syngas yield and LHV by 22 % and 21 %, respectively.

本研究探讨了松木二氧化碳辅助气化中加入石膏的潜在协同效应。松木和石膏之间的协同作用提高了松木转化为合成气的效率，同时也促进了石膏转化为化学上有价值的物质，如硫化钙。在气化过程中，松木产生了大量的焦油和非活性炭。焦油是一种相当稳定的化合物，在实现高转化效率方面存在重大障碍。石膏的存在提高了焦炭和焦油转化合成气的产率。这里提出的结果实证检验了不同数量的石膏对生产氢气（H2）和合成气的影响，在其二氧化碳辅助气化与松木。使用松木中16.67 wt.%的石膏，合成气的总收率提高了11.7%，LHV提高了12.5%。然而，将石膏质量分数增加到50%会对合成气产量产生负面影响，合成气产量和LHV分别降低22%和21%。

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引用次数: 0

Synthesis of TiO2 nanoparticles with (001) preferential plane for photovoltaic performance in DSSC 具有（001）光电性能优先面的TiO2纳米粒子的合成

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-29 DOI: 10.1016/j.sajce.2025.10.007

Paulina Vargas-Rodriguez , Carolina Silva-Carrillo , Brenda Alcantar-Vazquez , Rosa-María Félix-Navarro , Rosalío Velarde-Barraza , Edgar-Alonso Reynoso-Soto

In this work, we report the effect of temperature in the preparation of TiO₂ nanoparticles with spherical and quasi-octahedral shapes and a modulated surface area ranging from 103 to 245 m² g^-¹ using the peptization-hydrothermal method without porosity, size and shape controlling agents; varying the temperature to achieve particle sizes of 9 to 20 nm and porosities from 32 to 120 Å. It was observed that photovoltaic parameters were also modified. The TiO₂ samples were characterized by XRD, BET, TEM, DRS, TGA, and I-V curves. The increase in synthesis temperature correlates with particle and pore size, as well as a reduction in surface area. However, when the synthesis temperature was 210 °C, the surface area decreased by 42 %. The TiO₂ samples were used to prepare ethyl cellulose pastes for fabricating thin-film photoanodes in dye-sensitized solar cells (DSSCs). The photovoltaic results showed that the sample prepared at 180 °C exhibited the most suitable textural properties and crystalline orientation for DSSC applications.

在这项工作中，我们报告了温度对制备球形和准八面体形状的TiO2纳米粒子的影响，并在没有孔隙、尺寸和形状控制剂的情况下，使用peppeptich -hydrothermal法制备了103至245 m²g-¹的调制表面积；改变温度，以实现9至20纳米的颗粒尺寸和孔隙率从32到120 Å。观察到光伏参数也被修改。采用XRD、BET、TEM、DRS、TGA和I-V曲线对TiO2样品进行表征。合成温度的升高与颗粒和孔径大小以及表面积的减小有关。然而，当合成温度为210℃时，比表面积减少了42%。二氧化钛样品用于制备乙基纤维素浆料，用于染料敏化太阳能电池（DSSCs）的光电阳极薄膜。光伏结果表明，在180°C下制备的样品具有最适合DSSC应用的纹理性能和晶体取向。

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引用次数: 0

Toxic metal adsorption from gold tailings wastewater using biowaste biochars: A circular economy approach 利用生物炭吸附金尾矿废水中的有毒金属：一种循环经济方法

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-25 DOI: 10.1016/j.sajce.2025.10.006

Abudu Ballu Duwiejuah

Sustainable development of adsorbents from biowaste and their use for the treatment of wastewater is a circular economy approach. The study assessed the adsorption efficiency of biowaste biochars for heavy metal ions from gold tailings wastewater. Fourier transform infrared spectroscopy (FTIR) was employed to identify the functional groups and bond vibrations in the biowaste biochar. A total of 100 mL of the gold tailings wastewater was measured into a conical flask, and biowaste biochar dosage of 1.0, 2.0 and 3.0 g each was weighed and added, and then kept in a water bath at 30 °C and agitated at contact times of 20, 35 and 50 min. The corn cob biochar removes Cd (99.10 to 99.40%), Hg (90.50 to 93.80%), and Cr (15.60 to 75.60%) and Ni (21.30 to 84.50%), peanut shell biochar removes Cd (99.10 to 99.40%), Hg (90.60 to 93.80%), and Cr (19.10 to 77.80%) and Ni (35.50 to 85.30%) whilst sheanut shell biochar removes Cd (99.10 to 99.40%), Hg (89.40 to 93.80%), and Cr (8.90 to 73.30%) and Ni (35.50 to 87.10%). Corn cob biochar showed K_F for Cd (3.4 × 10¹¹ to 1.8 × 10¹⁷ mg/g), Hg (1.8 × 10⁶ to 8.0 × 10¹² mg/g), and Cr (0.01 to 1.4 mg/g) and Ni (0.1 to 0.03 mg/g). The corn cob biochar contains primary alcohol, alkane and carboxylic acids groups, peanut shell biochar contains aliphatic, tertiary alcohol, amine and secondary amines, and sheanut shell biochar contains aliphatic, primary alcohol, amine and carboxylic acids groups. The biochar dosage increases the cadmium, mercury, chromium, and nickel adsorption efficiency onto biowaste biochars. The dosage, porous surface, and time increase the adsorption efficiency of cadmium, mercury, chromium, and nickel significantly. The Freundlich model was the best fit model for cadmium and mercury adsorption onto the biochars due to the heterogeneous surface of the adsorbent, which makes it have a tougher binding site. Biowaste biochars demonstrated considerable potential for effectively removing heavy metal ions from gold tailings wastewater, making a valuable contribution to the circular economy and the remediation of environmental pollution.

从生物废物中可持续开发吸附剂并将其用于废水处理是一种循环经济方法。研究了生物炭对金尾矿废水中重金属离子的吸附效果。利用傅里叶变换红外光谱（FTIR）对生物炭中的官能团和键振动进行了识别。共取100 mL金尾矿废水量于锥形烧瓶中，称重后分别加入1.0、2.0、3.0 g的生物废生物炭，在30℃水浴中保持，接触时间分别为20、35、50 min。玉米芯生物炭脱除Cd（99.10 ~ 99.40%）、Hg（90.50 ~ 93.80%）、Cr（15.60 ~ 75.60%）和Ni(21.30 ~ 84.50%)，花生壳生物炭脱除Cd（99.10 ~ 99.40%）、Hg（90.60 ~ 93.80%）、Cr（19.10 ~ 77.80%）和Ni(35.50 ~ 85.30%)，花生壳生物炭脱除Cd（99.10 ~ 99.40%）、Hg（89.40 ~ 93.80%）、Cr（8.90 ~ 73.30%）和Ni（35.50 ~ 87.10%）。玉米芯生物炭对Cd （3.4 × 1011 ~ 1.8 × 1017 mg/g）、Hg （1.8 × 106 ~ 8.0 × 1012 mg/g）、Cr （0.01 ~ 1.4 mg/g）和Ni （0.1 ~ 0.03 mg/g）的KF值较高。玉米芯生物炭含有伯醇、烷烃和羧酸基团，花生壳生物炭含有脂肪族、叔醇、胺和仲胺，花生壳生物炭含有脂肪族、伯醇、胺和羧酸基团。生物炭的添加量提高了生物炭对镉、汞、铬和镍的吸附效率。添加量、多孔表面和时间均能显著提高镉、汞、铬、镍的吸附效率。Freundlich模型是生物炭吸附镉和汞的最佳拟合模型，因为吸附剂表面的非均质性使其具有较强的结合位点。生物垃圾生物炭在有效去除金尾矿废水中的重金属离子方面显示出相当大的潜力，为循环经济和环境污染的修复做出了宝贵的贡献。

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