South African Journal of Chemical Engineering最新文献_第10页

Preparation and characterization of eco-friendly polymer composites from leather wastes 皮革废弃物环保高分子复合材料的制备与表征

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-01 Epub Date: 2025-09-12 DOI: 10.1016/j.sajce.2025.09.009

Sanjida Khan , Md. Sahadat Hossain , Mohammad Al Shahriar Khan , Afrin Rahman Akhi , Md. Farhad Ali

A large amount of hazardous waste generated by tannery industries, particularly waste leather fibers like buffing dust and trimming waste, is a big concern for a green environment. The utilization of waste leather fibers in composite fabrication can be an effective way to subside environmental pollution. On the other hand, the quantity of synthetic polymer is increasing day by day, which is a great obstacle in the way of a clean and sustainable environment. The aim of this research is proper recycling of this leather waste as well as decreasing the use of synthetic polymer. In this research, waste leather fibers such as buffing dust and trimming dust were used as a reinforcing material and unsaturated polyester resin and epoxy resin as a polymeric matrix for composite fabrication by hand lay-up technique. Different percentages of leather fibers were added to the matrix material to significantly improve its physical and mechanical properties. This study represented that among all the fabricated composites, 10 % BD/UPR reinforced composite showed the highest enhancement of mechanical properties. This research successfully utilized waste leather fibers to fabricate cost effective composites which lessened environmental pollution. The highest values of TS and TM were achieved for optimal composite, which are 24.89 N/mm² and 1336.46 N/mm², respectively, which were 40 % and 167.38 % higher than the control sample. The water absorption behavior of the fabricated composites was evaluated by the water uptake test. To observe the stability temperature of the prepared composites, the thermogravimetric analysis (TGA) test was conducted up to 700°C. The FTIR was conducted for the functional group analysis of the fabricated composites. To observe the leather fiber-matrix adhesion, scanning electron microscopy (SEM) was carried out. To sum up, the prepared composites showed improved mechanical properties suitable for commercial applications.

制革业产生的大量有害废物，特别是抛光粉尘和修剪废料等废皮革纤维，是绿色环境的一个大问题。利用废皮革纤维制造复合材料是减少环境污染的有效途径。另一方面，合成聚合物的数量日益增加，这对清洁和可持续发展的环境是一个很大的障碍。本研究的目的是适当回收这些皮革废料，以及减少合成聚合物的使用。本研究以抛光尘和修边尘等废皮革纤维为增强材料，以不饱和聚酯树脂和环氧树脂为聚合物基体，采用手工铺层法制备复合材料。在基体材料中加入不同比例的皮革纤维，可显著改善基体材料的物理力学性能。研究表明，在所有制备的复合材料中，10%的BD/UPR增强复合材料的力学性能提高最高。本研究成功地利用废皮革纤维制备了低成本的复合材料，减少了对环境的污染。最优组合的TS和TM值分别为24.89 N/mm²和1336.46 N/mm²，分别比对照样品高40%和167.38%。通过吸水试验对复合材料的吸水性能进行了评价。为了观察制备的复合材料的稳定温度，在高达700℃的温度下进行了热重分析（TGA）测试。利用红外光谱对复合材料的官能团进行了分析。采用扫描电子显微镜（SEM）观察皮革纤维与基体的粘附情况。综上所述，制备的复合材料的力学性能得到了改善，适合于商业应用。

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引用次数: 0

Factors contributing to reduced photocatalytic activity in Cu-loaded TiO2/activated carbon composites for methylene blue degradation 负载cu的TiO2/活性炭复合材料降解亚甲基蓝的光催化活性降低的影响因素

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-01 Epub Date: 2025-09-27 DOI: 10.1016/j.sajce.2025.09.015

Nur Karimah , Risna Citra Andiani , Wahyu Prasetyo Utomo , Ade Irma Rozafia , Nor Farida , Afifah Rosyidah , Rui Liu , Qili Xu , Djoko Hartanto

TiO₂ is a semiconductor widely used in photocatalytic applications due to its excellent chemical stability, yet it has a low surface area. Incorporating TiO₂ on the surface of activated carbon via a hydrothermal process could enlarge its surface area, and therefore the photocatalytic activity. Theoretically, metal deposition on the surface of TiO₂ could create a Schottky junction, which suppresses charge recombination and enhances photocatalytic activity. Herein, we report Cu deposition on the surface of TiO₂ anchored on activated carbon (Cu-TiO₂/AC) for photocatalytic degradation of methylene blue. The Cu was deposited by a photodeposition process under UV irradiation. In contrast to the conventional hypothesis, that the Cu deposition on TiO₂/AC could exhibit an enhanced photocatalytic activity, our current result shows that the material exhibits a decrease in photocatalytic activity compared to the pristine TiO₂/AC. The same trend was also observed in other TiO₂ samples with different morphology upon Cu photodeposition. The decrease in photocatalytic activity could be correlated with the size of Cu nanoparticles and the oxidation state of Cu species. The photodeposition typically produces a relatively large Cu nanoparticle, which may serve as the recombination center for the charge carriers. Moreover, the existence of Cu⁺ and Cu²⁺ species, in addition to Cu⁰, could consume the transferred e^- from TiO₂, decreasing the e^- efficiency. This work implies that ensuring the small particle size and the existence of monovalent Cu⁰ species are critical factors for using Cu as a co-catalyst in photocatalyst materials.

TiO2是一种广泛应用于光催化领域的半导体，具有优异的化学稳定性，但其比表面积较小。通过水热法将TiO2吸附在活性炭表面，可以扩大活性炭的表面积，从而提高其光催化活性。理论上，在TiO2表面沉积金属可以形成肖特基结，从而抑制电荷重组，提高光催化活性。在此，我们报道了Cu沉积在固定在活性炭（Cu-TiO2/AC）上的TiO2表面，用于光催化降解亚甲基蓝。在紫外照射下，采用光沉积法沉积铜。与传统的假设相反，Cu沉积在TiO2/AC上可以表现出增强的光催化活性，我们目前的结果表明，与原始的TiO2/AC相比，该材料的光催化活性有所下降。在其他不同形貌的TiO2样品中也观察到同样的趋势。光催化活性的降低可能与Cu纳米颗粒的大小和Cu的氧化态有关。光沉积通常会产生较大的铜纳米颗粒，它可以作为载流子的重组中心。此外，除了Cu0外，Cu+和Cu2+的存在也会消耗TiO2转移的e-，降低e-效率。这项工作表明，确保小颗粒尺寸和单价Cu0的存在是在光催化剂材料中使用Cu作为助催化剂的关键因素。

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引用次数: 0

Enhanced parrot optimizer for Meridianin derivative design: Synthesis optimization, biological evaluation, and molecular docking insights 用于子午线素衍生物设计的增强型鹦鹉优化器：合成优化、生物评价和分子对接见解

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-01 Epub Date: 2025-07-16 DOI: 10.1016/j.sajce.2025.06.012

Mohanad A. Deif , Mohamed Elhoseny , Mohamed A. Hafez , Waleed Alomoush , Mohammad Khishe

Meridianin derivatives, which were discovered to possess multifarious biological activities, have excellent potential to be used as multifunctional therapeutic agents, particularly in cancer and oxidative stress-related disease treatments. However, the challenges associated with increasing their synthesis and defining SARs have limited their extensive application. This study attempts to overcome these challenges by using an Enhanced Parrot Optimizer (EnPO), a highly efficient metaheuristic algorithm, to optimize key synthesis parameters, including reaction temperature, time, and solvent ratio, in an attempt to maximize the yield and purity of the reaction.

The optimized synthesis conditions were evaluated through computational modeling, while in silico biological activity was assessed via molecular docking simulations. Docking experiments revealed strong interactions between meridianin derivatives and major protein targets. Comparative studies confirmed that EnPO outperformed conventional optimization techniques, such as PSO, GA, and ACO, in terms of convergence speed, solution quality, and robustness.

The novelty of this study lies in the development and application of a behaviorally adaptive optimizer (EnPO), integrating hierarchical guidance, mimicry dynamics, and weighted behavior selection—features absent in traditional algorithms. This work represents the first integration of such an optimizer for simultaneous computational optimization and biological evaluation of meridianin derivatives.

The findings reported that the optimal synthesis parameters yielded meridianin derivatives with a reaction yield of 92.3 % and purity of 95.4 %. Compound 3b demonstrated the highest cytotoxicity, exhibiting 95.2 % inhibition of MCF7 cells, and the lowest IC50 value for antioxidant activity at 42.5 µg/mL. The docking results showed high binding affinities, with compound 3b exhibiting the best binding energy to EGFR at -9.2 kcal/mol through hydrogen bonding and π-π stacking interactions.This study demonstrates the efficacy of the Enhanced Parrot Optimizer for driving chemical synthesis optimization and highlights the therapeutic potential of meridianin derivatives as multi-target agents.

经研究发现，经络素衍生物具有多种生物活性，在治疗癌症和氧化应激相关疾病方面具有良好的潜力。然而，与增加合成和定义非典型肺炎相关的挑战限制了它们的广泛应用。为了克服这些挑战，本研究使用了一种高效的元启发式算法——Enhanced Parrot Optimizer （EnPO）来优化关键的合成参数，包括反应温度、时间和溶剂比，以最大限度地提高反应的收率和纯度。通过计算模型评价优化后的合成条件，通过分子对接模拟评价其在硅中的生物活性。对接实验显示，经络素衍生物与主要蛋白靶点之间存在很强的相互作用。对比研究证实，EnPO在收敛速度、解质量和鲁棒性方面优于传统的优化技术，如PSO、GA和ACO。本研究的新颖之处在于行为自适应优化器（EnPO）的开发和应用，该优化器集成了传统算法中缺乏的分层引导、模仿动力学和加权行为选择等特征。这项工作代表了这种优化器的首次集成，用于同时计算优化和子午线衍生物的生物学评估。结果表明，在最佳合成条件下，得到的子午线素衍生物的反应收率为92.3%，纯度为95.4%。化合物3b显示出最高的细胞毒性，对MCF7细胞的抑制作用为95.2%，抗氧化活性的IC50值最低，为42.5µg/mL。对接结果表明，化合物3b通过氢键和π-π堆叠相互作用与EGFR的结合能最高，为-9.2 kcal/mol。本研究证明了增强型Parrot Optimizer在推动化学合成优化方面的功效，并强调了经络素衍生物作为多靶点药物的治疗潜力。

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引用次数: 0

Natural meatball preservative using edible coating from modified shrimp shells chitosan and durian skin liquid smoke 天然肉丸防腐剂采用可食用涂层，由改性虾壳、壳聚糖和榴莲皮烟熏液制成

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-01 Epub Date: 2025-07-31 DOI: 10.1016/j.sajce.2025.07.014

Muhammad Faisal , Suraiya Kamaruzzaman , Mukhlishien , Hera Desvita

This research aimed to evaluate the ability of edible coating from a combination of shrimp shell chitosan and durian skin liquid smoke to extend the shelf life of meatball. In this context, an edible coating was made by dissolving chitosan with various concentrations of 1 % (C1), 1.5 % (C2) and C3 (2 %) into liquid smoke at temperatures (300 °C (T1), 340 °C (T2), 380 °C (T3), and T4 (420 °C). Furthermore, preservation was performed by soaking the meatball in a solution for 15 min and storing at room temperature. The observations of the decrease in the durability of the meatball were carried out every 4 h for 5 days. Considering this, the ability to preserve meatball was evaluated through the Total Volatile Base-Nitrogen (TVB-N) test, Total Plate Count (TPC), antibacterial activity test, and Most Probable Number (MPN) Escherichia coli. The results showed that edible coating with 2 % chitosan concentration provided the best durability, with a shelf life of 88 h before a significant decrease in quality. The TVB-N value remained within safe limits (<20.45 mgN/100 g), while the 4.37 × 10⁴ CFU/g of bacterial colonies were below the maximum standard of 80 h. The edible coating exhibited notable antibacterial activity, as evidenced by inhibition zone diameters of 6.37, 6.09, 8.05, and 7.63 mm againts Staphylococcus aureus, Bacillus subtilis, E. coli, and Salmonella enterica sv. Typhimurium, respectively. The MPN test showed that the sample with 2 % chitosan was within the consumption limits of 68 h. Therefore, edible coating based on durian skin liquid smoke-chitosan was an effective and environmentally friendly alternative in extending the shelf life of meatball and could also reduce the use of synthetic preservatives in the food industry.

研究了虾壳壳聚糖与榴莲皮液烟复合可食用涂层对肉丸保质期的影响。在这种情况下，将不同浓度的壳聚糖(1% （C1), 1.5% （C2）和C3(2%)）在300°C (T1), 340°C (T2), 380°C （T3）和T4（420°C）的温度下溶解在液体烟雾中，制成可食用的涂层。此外，保存的方法是将肉丸浸泡在溶液中15分钟，并在室温下保存。每隔4小时观察一次肉丸的耐久性下降情况，持续5天。考虑到这一点，通过总挥发性碱基氮（TVB-N）测试、总平板计数（TPC）测试、抗菌活性测试和大肠杆菌最可能数（MPN）测试来评估肉丸的保存能力。结果表明，壳聚糖浓度为2%时，食用包衣的耐久性最佳，保存期为88 h，之后质量显著下降。ttb - n值保持在安全范围内（20.45 mgN/100 g），而菌落4.37 × 10⁴CFU/g低于80 h的最大标准。可食用涂层表现出显著的抗菌活性，对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌和肠炎沙门氏菌的抑菌带直径分别为6.37、6.09、8.05和7.63 mm。分别培养。MPN试验结果表明，添加2%壳聚糖的样品在68 h的食用极限内。因此，基于榴莲皮液体烟熏壳聚糖的食用涂层是一种有效的、环保的延长肉丸保质期的替代品，也可以减少食品工业中合成防腐剂的使用。

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引用次数: 0

Enhancing the delivery of Fluid Mechanics education through the use of low-cost phone-based particle streak velocimetry 通过使用低成本的基于手机的粒子条纹测速，加强流体力学教育的传授

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-01 Epub Date: 2025-09-08 DOI: 10.1016/j.sajce.2025.09.002

Jeffrey K. Muriithi , Fabian Nachbur , Josephat K. Tanui , Godfrey K. Gakingo

To enhance the delivery of Fluid mMechanics, engineering instructors have found practical laboratory experiments to be a useful complementary tool. Various experimental methods have been adopted with recent interest being in the use of low-cost particle image velocimetry (PIV). This technique involves seeding of a flow with particles, recording the particles’ motion using low-cost components and thereafter analysing the generated images using open-source software to give velocity information. Low-cost PIV has been found to be feasible for educational demonstration purposes though the use of low-cost components (such as mobile phone cameras) has limited the applicability of the technique to slow flows. To overcome this limitation while keeping the noble idea of a low-cost particle velocimetry technique, this study proposes the use of low-cost particle streak velocimetry (PSV) instead. The PSV technique relies on a set up similar to that used for low-cost PIV. However, its analysis procedure requires only one image and the camera’s exposure time (or shutter speed) which can be readily controlled in low-cost cameras. In comparison, low-cost PIV requires two images and the timestep between the images which is fixed by the camera’s framerate (low-cost cameras have low framerates). This study therefore tests whether low-cost PSV technique can be used to attain higher velocities in comparison to low-cost PIV. The concept has been tested on an air jet produced from a laboratory-type Bunsen burner, with velocities in the order of 800 mm/s measured which were comparatively higher than those reported in low-cost PIV literature (250 mm/s). In addition, good accuracy was achieved by the method with the mean velocity measured to within 4 % of the theoretical value.

为了加强流体力学的传授，工程讲师发现实际的实验室实验是一个有用的补充工具。采用了各种实验方法，最近的兴趣是使用低成本的粒子图像测速（PIV）。这项技术包括用粒子播种流，用低成本的组件记录粒子的运动，然后用开源软件分析生成的图像来给出速度信息。低成本的PIV已被发现可用于教育演示目的，尽管使用低成本组件（如移动电话相机）限制了该技术在减缓流量方面的适用性。为了克服这一限制，同时保持低成本粒子测速技术的崇高理念，本研究提出使用低成本粒子条纹测速（PSV）代替。PSV技术依赖于类似于用于低成本PIV的设置。然而，它的分析过程只需要一张图像和相机的曝光时间（或快门速度），这在低成本相机中很容易控制。相比之下，低成本的PIV需要两幅图像和图像之间的时间步长，这是由相机的帧率固定的（低成本相机的帧率低）。因此，本研究测试了低成本的PSV技术是否可以比低成本的PIV技术获得更高的速度。该概念已在实验室型本生灯产生的空气射流上进行了测试，测量的速度约为800毫米/秒，比低成本PIV文献（250毫米/秒）报道的速度要高。此外，该方法测量的平均速度与理论值的误差在4%以内，具有较好的精度。

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引用次数: 0

Green fabrication of p-n CuO/ZnO heterojunctions for efficient photocatalytic degradation of dyes 绿色制备用于高效光催化降解染料的p-n CuO/ZnO异质结

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-01 Epub Date: 2025-09-10 DOI: 10.1016/j.sajce.2025.09.007

Atheel Alwash

The heterojunction photocatalyst of CuO/ZnO has attracted considerable interest due to its superior ability to degrade organic pollutants through photocatalytic processes. In this research, CuO/ZnO heterojunctions were successfully synthesized by thermal combustion technique. The structural, morphological, and optical characteristics of the resulting materials were extensively analyzed using various characterization methods. Diffraction studies confirmed the presence of both CuO and ZnO phases, with an average crystalline size of 29.625 nm. These findings were corroborated by TEM analysis, which also highlighted the particle size and geometric shape. BET analysis revealed a mesoporous structure with a surface area of 4.18 m²/g. The band gap energy of the catalyst was determined to be 1.48 eV, attributed to the interaction between copper and zinc oxides. The Photoluminescence (PL) indicates the reduction in PL intensity of CuO-ZnO/GA compared to ZnO/GA ascribed to the reduction in electron–hole Coulombic attraction. The photocatalytic efficiency of the CuO/ZnO heterojunction was assessed by its degradation of methylene blue (MB) dye, achieving 97% removal. This enhanced in catalytic efficiency was attributed to the effective separation of electron-hole pairs and the extended absorption range into the visible light spectrum.

CuO/ZnO异质结光催化剂由于其优异的光催化降解有机污染物的能力而引起了人们的广泛关注。在本研究中，利用热燃烧技术成功合成了CuO/ZnO异质结。使用各种表征方法广泛分析了所得材料的结构、形态和光学特性。衍射研究证实了CuO相和ZnO相的存在，平均晶粒尺寸为29.625 nm。这些发现被TEM分析证实，也突出了颗粒的大小和几何形状。BET分析显示，该材料具有4.18 m²/g的介孔结构。结果表明，该催化剂的带隙能为1.48 eV，为氧化铜和氧化锌相互作用的结果。光致发光（PL）表明，与ZnO/GA相比，CuO-ZnO/GA的发光强度降低是由于电子-空穴库仑吸引力的降低。通过对亚甲基蓝（MB）染料的降解，评价了CuO/ZnO异质结的光催化效率，去除率达到97%。催化效率的提高是由于电子-空穴对的有效分离和可见光吸收范围的扩大。

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引用次数: 0

Experimental evaluation of product yield by pyrolysis of medical waste: a way of energy recovery 医疗废弃物热解产率的实验评价：一种能量回收方法

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-01 Epub Date: 2025-07-11 DOI: 10.1016/j.sajce.2025.07.001

Md. Abdullah Al- Mamun , Md. Mushrafi Al- Mueed , Md. Hasan Ali

The proper management of medical waste is a significant global concern, requiring new disposal methods while also recovering energy. This paper explores the viability of energy recovery from medical waste by pyrolysis with a focus on experimentally evaluating the product yield. To conduct the pyrolysis process, an external heating batch reactor was built, where various types of medical waste, including saline bottles, syringes, and medical gloves, were thermally degraded. The main goals of the study were to investigate the effects of varying medical waste mixtures and temperatures on product yields and to determine the physicochemical properties of the produced pyrolytic oil. The maximum yield of liquid products was about 59.5 % at 350 °C for the saline bottle-syringe blend. The maximum liquid yield for the hand gloves-saline bottle blend, hand gloves-syringe blend, and saline bottle-syringe-hand gloves blend was 49 %, 48 %, and 50 %, respectively, at 400 °C. These yields were slightly lower than the saline bottle-syringe blend due to the presence of rubber compound hand gloves in these mixtures. The pyrolytic oil exhibited a density range from 777.5–849.3 kg/m³, while its viscosity ranged from 1.15–2.1 cSt. The flash point of the oil ranged from 38–41 °C, and the boiling point ranged from 99–129 °C. The calorific value of pyrolytic oil was found to be 41.1 MJ/kg, which is very close to that of conventional fuels. The FTIR analysis of the pyrolytic oil samples showed characteristic functional groups, primarily alkanes and alkenes. The findings reveal insights into the optimal conditions for maximizing product yield and highlight the potential of pyrolysis as a viable method for both waste management and energy recovery within the medical sector. This study contributes to the advancement of sustainable practices in healthcare waste management and underscores the importance of exploring alternative energy sources for a more environmentally conscious future.

医疗废物的适当管理是全球关注的一个重大问题，需要新的处理方法，同时也要回收能源。本文探讨了医疗废物热解回收能源的可行性，重点是实验评估了产物收率。为了进行热解过程，我们建立了一个外部加热间歇式反应器，对各种类型的医疗废弃物进行热降解，包括生理盐水瓶、注射器、医用手套等。该研究的主要目的是研究不同医疗废物混合物和温度对产品产量的影响，并确定所产生的热解油的物理化学性质。在350°C时，生理盐水瓶-注射器混合物的最大产率约为59.5%。在400℃时，手套-生理盐水瓶混合物、手套-注射器混合物和生理盐水瓶-注射器-手套混合物的最大产液率分别为49%、48%和50%。由于在这些混合物中存在橡胶复合手套，这些产量略低于盐水瓶-注射器混合物。热解油的密度为777.5 ~ 849.3 kg/m3，粘度为1.15 ~ 2.1 cSt。油的闪点在38-41℃之间，沸点在99-129℃之间。热解油的热值为41.1 MJ/kg，与常规燃料的热值非常接近。热解油样品的FTIR分析显示了特征官能团，主要是烷烃和烯烃。研究结果揭示了最大化产品产量的最佳条件，并强调了热解作为医疗部门废物管理和能源回收的可行方法的潜力。这项研究有助于促进医疗废物管理的可持续实践，并强调了探索替代能源的重要性，以实现更具环保意识的未来。

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引用次数: 0

Physicochemical characterization and kinetic study of anaerobic digestion of cattle dung in a semi-batch reactor 牛粪半间歇反应器厌氧消化的理化特性及动力学研究

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-01 Epub Date: 2025-08-30 DOI: 10.1016/j.sajce.2025.08.016

E.L. Odekanle , O.S. Teniola , I.O. Olaoye , O.A. Falowo , J. Undiandeye

This study investigated the process kinetics of the anaerobic digestion of different wastes under mesophilic conditions. A slurry of cattle dung was anaerobically digested in fabricated 25-litre reactors for 24 days. The biogas volume, physicochemical, and microbial properties of the digesting slurry were determined every three days using standard procedures. Kinetic models based on the first-order, Monod, and Grau second-order expressions were employed to estimate the performance of the process. After the experiment, a cumulative 0.0265 m³ of biogas was produced, and significant variations in the physicochemical and microbial properties of the digestate were observed. The process kinetics of the digestion followed a first-order reaction with a rate constant of 0.0526 day^-1 and 75.1 % COD removal efficiency. For the Monod model, the maximum rate of substrate utilization and saturation constant was found to be 0.1107 day^-1 and 1326.34 mg/l respectively. Based on analytical parameter, this anaerobic digestion process followed both first-order kinetic and Monod models only, which shows that for maximum biogas production from animal waste, inoculation would be required.

研究了中温条件下不同废物厌氧消化的过程动力学。牛粪浆液在自制的25升反应器中厌氧消化24天。利用标准程序每三天测定一次沼液的沼气量、理化性质和微生物特性。采用基于一阶、Monod和Grau二阶表达式的动力学模型来估计该过程的性能。实验结束后，累计产生了0.0265 m³的沼气，并观察到消化液的理化和微生物特性发生了显著变化。消化过程动力学符合一级反应，速率常数为0.0526 d -1， COD去除率为75.1%。在Monod模型中，底物利用率和饱和常数的最大值分别为0.1107 day-1和1326.34 mg/l。根据分析参数，该厌氧消化过程仅符合一级动力学模型和Monod模型，这表明为了最大限度地利用动物粪便产生沼气，需要接种。

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引用次数: 0

Degradation of rhodamine B Dye on BiOIO3/Bi12O17Cl2 heterostructure photocatalyst under visible light activation 可见光活化下biio3 /Bi12O17Cl2异质结构光催化剂降解罗丹明B染料

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-01 Epub Date: 2025-07-14 DOI: 10.1016/j.sajce.2025.07.005

Osemeikhian Ogbeifun, Shepherd M. Tichapondwa, Evans M.N. Chirwa

Dye pollution resulting from industrial waste poses a substantial threat to both human health and the environment. Heterostructure composites of BiOIO₃ and Bi₁₂O₁₇Cl₂ with varying mass ratios (BiOIO₃/B_i12O₁₇Cl₂-y:x) were fabricated to enhance the degradation abilities of the individual material towards dye contaminants. The rapid recombination of photogenerated electron-hole pairs in Bi₁₂O₁₇Cl₂ and the limited photon utilisation of the visible light wavelengths by BiOIO3 were addressed in the heterojunction. The heterojunction formed between the material provides for spatial charge separation and boost of redox power of photogenerated electrons and holes. The degradation rate constant of Rhodamine B dye on BiOIO₃/Bi₁₂O₁₇Cl₂–1:1, the best performing material, under visible light in 6 h was 0.4 h⁻¹, which is 2.7 and 4.3 times the rate constants for Bi₁₂O₁₇Cl₂ (0.149 h⁻¹) and BiOIO₃ (0.093 h⁻¹), respectively. The results demonstrate the contribution of heterostructure formation in improving the photocatalytic degradation process. The main species in the degradation step are hydroxyl (•OH) and superioxide (•O₂^–) radicals. BiOIO₃/Bi₁₂O₁₇Cl₂–1:1 has good photocatalytic stability, as 96 % efficiency retention is reported after four cycles. Thus, BiOIO₃/Bi₁₂O₁₇Cl₂–1:1 is a promising material for the degradation of dyes.

工业废料造成的染料污染对人类健康和环境都构成重大威胁。制备了具有不同质量比（BiOIO3/Bi12O17Cl2-y:x）的biio3和Bi12O17Cl2异质结构复合材料，以提高单个材料对染料污染物的降解能力。在异质结中解决了Bi12O17Cl2中光生电子-空穴对的快速复合和BiOIO3对可见光波长的有限光子利用问题。材料之间形成的异质结提供了空间电荷分离和光生电子和空穴的氧化还原功率的增强。在可见光下，罗丹明B染料在性能最好的材料BiOIO3/Bi12O17Cl2 - 1:1上的降解速率常数为0.4 h−1，分别是Bi12O17Cl2 （0.149 h−1）和BiOIO3 （0.093 h−1）的2.7和4.3倍。结果表明异质结构的形成对改善光催化降解过程的贡献。降解过程中的主要自由基是羟基（•OH）和超氧自由基（•O2 -）。BiOIO3/ Bi12O17Cl2-1:1具有良好的光催化稳定性，经过4次循环后效率保持在96%。因此，BiOIO3/ Bi12O17Cl2-1:1是一种很有前途的染料降解材料。

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引用次数: 0

Application of edible coating based on durian seed starch and peel liquid smoke as natural preservatives for tomatoes (Solanum Lycopersicum L.) 以榴莲籽淀粉和果皮液烟为基料的食用涂料在番茄天然防腐剂中的应用

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-10-01 Epub Date: 2025-07-26 DOI: 10.1016/j.sajce.2025.07.003

Muhammad Faisal , Fauzi , Yusya Abubakar , M.Bagas Heriansyah , Hera Desvita

This study aimed to examine the effectiveness of edible coating formulated from durian seed waste and liquid smoke derived from peel in extending the storage period of tomatoes. Liquid smoke was obtained through the pyrolysis process of durian peel at three different temperatures, namely 340 °C (T1), 380 °C (T2), and 420 °C (T3), and incorporated into liquid smoke at concentrations of 2 % (K1), 4 % (K2), and 6 % (K3), starch and chitosan. Furthermore, antimicrobial test of edible coating was carried out through antibacterial activity tests against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. The test was also carried out through antifungal activity tests against Aspergillus niger and Candida albicans. The results of the antibacterial test showed that the inhibition zone against S. aureus and E. coli ranged from 6.017 - 6.107 mm and 12.983 - 21.220 mm, respectively. Antifungal activity test showed that the inhibition zone against A. niger and C. albicans ranged from 8.93 - 10.08 mm and 7.07 - 7.843 mm, respectively. Meanwhile, the analysis of edible coating on tomatoes included measuring the thickness of coating, weight loss, color analysis, and respiration rate. The coating reduced tomato weight loss to 6.60–8.69 %, maintained surface brightness (especially in T1K3), and decreased respiration rate. This research demonstrates a sustainable postharvest preservation method using agricultural waste, aligning with current trends in biodegradable food packaging.

研究了以榴莲籽渣为原料配制的食用包衣和果皮提取液烟对番茄保鲜期的影响。将榴莲皮在340℃（T1）、380℃（T2）和420℃（T3）三种不同温度下热解得到液烟，并以2% （K1）、4% （K2）和6% （K3）的浓度与淀粉和壳聚糖混合制成液烟。通过对革兰氏阴性菌（大肠杆菌）和革兰氏阳性菌（金黄色葡萄球菌）的抑菌活性试验，对食用涂层进行抗菌试验。同时对黑曲霉和白色念珠菌进行了抗真菌活性试验。抑菌试验结果表明，对金黄色葡萄球菌和大肠杆菌的抑菌带范围分别为6.017 ~ 6.107 mm和12.983 ~ 21.220 mm。抑菌活性试验表明，对黑僵菌和白色念珠菌的抑菌区分别为8.93 ~ 10.08 mm和7.07 ~ 7.843 mm。同时，对番茄可食用涂层的分析包括涂层厚度测定、失重、颜色分析和呼吸速率。涂层使番茄失重率降低到6.60 - 8.69%，保持了番茄表面亮度（尤其是在T1K3中），并降低了呼吸速率。本研究展示了一种利用农业废弃物的可持续的采后保鲜方法，符合当前生物可降解食品包装的趋势。

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引用次数: 0