South African Journal of Chemical Engineering最新文献

Zeolite pellet fabrication for biogas purification: Characterization and CO2 adsorption performance 用于沼气净化的沸石颗粒制备：表征和CO2吸附性能

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-08 DOI: 10.1016/j.sajce.2026.01.004

Bambang Trisakti , Rivaldi Sidabutar , Irvan Irvan , Farida Hanum , Mhd. Rivaldi Syahputra , Hani Suhastifa Rambe , Noersukma Dwi Gusty , Muhammad Syaifan , Michael Michael , Thiodorus Marvin Tjandra , Sheylin Wimora Lumban Tobing , Peer Mohamed Abdul

The escalating urgency for renewable energy solutions and sustainable waste management strategies has intensified research into biogas purification technologies, particularly addressing the critical need for efficient CO₂ removal to enhance methane concentration. This study optimized zeolite pellet fabrication and evaluated their CO₂ adsorption performance for biogas purification. Zeolite samples were systematically processed through pelletization and calcination procedures, with experimental parameters encompassing particle sizes (50-140 mesh), calcination temperatures (200-400^○C), and durations (2-4 hours). The pelletization process achieved optimal yield performance of 75.97±0.70% under conditions of 50 mesh particle size, 200^○C calcination temperature, and 2-hour duration, corresponding to maximum pellet density of 1.94±0.03 g/cm³. Water adsorption capacity reached its peak at 3.35±0.11% utilizing 140 mesh zeolite calcined at 400^○C for 4 hours. Most significantly, CO₂ removal efficiency achieved 92.5±0.75% under optimal conditions of 140 mesh particle size, 400^○C calcination temperature, and 4-hour calcination duration. Comprehensive characterization revealed crystallite size reduction from 53.31 nm to 37.41 nm following activation, while scanning electron microscopy confirmed heterogeneous pore structure with grain-like surface morphology. Energy dispersive X-ray spectroscopy analysis indicated substantial oxygen content increase from 31.31% to 58.30% post-CO₂ adsorption, accompanied by carbon content decrease from 30.59% to 5.54%. N₂ adsorption quantified surface area, pore volume, and pore diameter as 283.01 m²/g, 0.292 cc/g, and 2.569 Å, respectively. These findings establish zeolite pellets as highly effective CO₂ adsorbents with substantial potential for industrial-scale biogas purification implementation.

对可再生能源解决方案和可持续废物管理战略的日益迫切需要加强了对沼气净化技术的研究，特别是解决了有效去除二氧化碳以提高甲烷浓度的迫切需要。本研究优化了沸石颗粒的制备工艺，并对其吸附CO2净化沼气的性能进行了评价。沸石样品通过制球和煅烧程序进行系统处理，实验参数包括粒度（50-140目），煅烧温度（200-400ºC）和持续时间（2-4小时）。在粒径为50目、焙烧温度为200℃、焙烧时间为2 h的条件下，制球工艺的最佳产率为75.97±0.70%，最大制球密度为1.94±0.03 g/cm3。140目沸石在400℃下煅烧4小时，吸附量达到3.35±0.11%。最显著的是，在粒径为140目、煅烧温度为400℃、煅烧时间为4 h的最佳条件下，CO2去除率达到92.5±0.75%。综合表征表明，活化后的晶体尺寸从53.31 nm减小到37.41 nm，扫描电镜证实了非均质孔隙结构，表面形貌呈颗粒状。能量色散x射线能谱分析表明，co2吸附后氧含量从31.31%上升到58.30%，碳含量从30.59%下降到5.54%。N2吸附测定的比表面积、孔体积和孔径分别为283.01 m2/g、0.292 cc/g和2.569 Å。这些研究结果表明，沸石颗粒是一种高效的二氧化碳吸附剂，在工业规模的沼气净化实施中具有巨大的潜力。

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引用次数: 0

Polynomial regression analysis on electromagnetohydrodynamic hybrid nanofluid flow over a rotating disk: Applications in next-generation thermal systems 旋转圆盘上电磁流体动力混合纳米流体流动的多项式回归分析：在下一代热系统中的应用

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.sajce.2025.12.010

Gunisetty Ramasekhar , P.D. Selvi , Hijaz Ahmad , Waleed Mohammed Abdelfattah

Thermal systems need effective cooling and heating processes, therefore thermal transfer innovation is critical in modern times, playing an important role in the manufacturing, aerospace, and electronic equipment sectors, in addition to automobiles and other modes of transportation. This study investigates the heat transfer properties of an electromagnetohydrodynamic mixed nanofluid across a porous spinning disk. The primary goal is to develop and validate an efficient engine oil/Cu-CuO hybrid framework that integrates traditional numerical approaches with polynomial regression analysis to accurately predict the flow and thermal features of complex nanofluid systems. The conversion of PDEs into ODEs is achieved by utilizing similarity variables. Thereafter, for graphical purposes, the study employed the bvp4c numerical method. The resultant structure is solved with the bvp4c scheme, and polynomial regression analysis is created to train the solution data for accurate estimation across different parameter (Q, Ec, Rd) settings. The suggested polynomial regression analysis has regression coefficients are 0.98, 0.87, 0.97, indicating high predicted accuracy and effectiveness. The influence of different parameters participating in the mathematical modeling is shown in various graphs and tables. In the result section the investigation noticed the velocity outlines increased, and on the other hand, there was a decreasing tendency in the energy outline for enlarging electric field parameter values. The heat generation and eckert number parameter values are increased, resulting in an improved energy profile. The results of this simulation have the potential to contribute significantly to more advanced study and research in the fields of bioengineering and bio-nanofluid dynamics.

热系统需要有效的冷却和加热过程，因此热传递创新在现代至关重要，除了汽车和其他运输方式外，在制造业，航空航天和电子设备领域也发挥着重要作用。本文研究了电磁流体混合纳米流体在多孔旋转盘上的传热特性。主要目标是开发和验证一种高效的发动机油/Cu-CuO混合框架，该框架将传统的数值方法与多项式回归分析相结合，以准确预测复杂纳米流体系统的流动和热特征。利用相似性变量实现了偏微分方程到偏微分方程的转换。此后，为了图解的目的，本研究采用了bvp4c数值方法。用bvp4c方案求解得到的结构，并创建多项式回归分析来训练解数据，以便在不同参数（Q, Ec, Rd）设置下进行准确估计。建议的多项式回归分析的回归系数分别为0.98、0.87、0.97，表明预测精度和有效性较高。参与数学建模的不同参数的影响以各种图形和表格的形式显示。结果段速度轮廓增大，电场参数值增大时能量轮廓减小。热量产生和埃克特数参数值增加，从而改善了能量剖面。该模拟的结果有可能为生物工程和生物纳米流体动力学领域的更高级研究做出重大贡献。

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引用次数: 0

Manipulating calcination temperature on crystal structure and optical properties tuning of CuO nanostructures 控制煅烧温度对CuO纳米结构晶体结构和光学性质的影响

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.sajce.2026.01.002

Arrak Klinbumrung , Reungruthai Sirirak , Samor Boonphan , Atit Wannawek , Yanee Keereeta

The research investigated the influence of calcination temperature on the properties of CuO nanostructures synthesized through a chemical precipitation method. Calcination at different temperatures (200, 400, and 600°C) significantly affected the crystal structure, morphology, and optical characteristics of the CuO nanostructures. Various characterization techniques were employed, including thermogravimetric analysis (TG), X–ray diffractometers (XRD), Fourier transform infrared spectrometers (FT–IR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). TG analysis revealed thermal behavior and phase transitions, while XRD results confirmed a monoclinic structure of CuO at 200°C with the calculation of the texture coefficient, crystallite size, lattice constants, strain, and other physical properties. SEM images showed a transition from nanorods to plate structures with increasing calcination temperature. TEM images demonstrated the highly crystalline characteristics of CuO samples. The BET analysis depicted surface area reduction, and CuO nanostructures exhibited energy band gaps ranging from 2.23 to 2.78 eV. Calculating optical terms as a function of photon energy also examined optical behaviors. Photoluminescence spectra revealed oxygen and copper vacancy defects, which sublevels affected energy bandgap change. The 400CuO sample exhibited the strongest PL emission signal, indicating the highest crystallinity and the lowest degree of defects. The findings underscored the significant impact of calcination temperature on the morphology and optical properties of CuO nanostructures, providing insights into their structural characteristics and emerging defects. The study supports opto-electronic applications and contributes to the global goal of pollution control and clean water.

研究了煅烧温度对化学沉淀法合成的氧化铜纳米结构性能的影响。不同温度（200℃、400℃和600℃）的煅烧对CuO纳米结构的晶体结构、形貌和光学特性有显著影响。采用了各种表征技术，包括热重分析（TG）、x射线衍射（XRD）、傅里叶变换红外光谱仪（FT-IR）、扫描电子显微镜（SEM）和透射电子显微镜（TEM）。TG分析揭示了CuO的热行为和相变，XRD结果通过计算织构系数、晶粒尺寸、晶格常数、应变等物理性质，证实了CuO在200℃时为单斜晶结构。SEM图像显示，随着煅烧温度的升高，纳米棒结构向板状结构转变。TEM图像显示CuO样品具有高度结晶性。BET分析显示CuO纳米结构的表面积减小，其能带隙在2.23 ~ 2.78 eV之间。计算光学项作为光子能量的函数也检查了光学行为。光致发光光谱显示出氧和铜空位缺陷，这些空位缺陷亚能级影响能隙的变化。400CuO样品的PL发射信号最强，表明结晶度最高，缺陷程度最低。这些发现强调了煅烧温度对CuO纳米结构的形貌和光学性质的重要影响，为其结构特征和新出现的缺陷提供了见解。该研究支持光电应用，有助于实现污染控制和清洁水的全球目标。

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引用次数: 0

Development and analysis of PVC glass slides for urine microstructure studies 尿液微结构研究用PVC玻片的研制与分析

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.sajce.2025.12.018

Mohammed Alwan Farhan, Luma Salman Abd, Zaid H. Mahmoud

The long-term maintenance of urine precipitation microstructures stays a main restriction in medical laboratory education and routine urinalysis, as traditional glass sides typically permit sample stability for only 1–3 h. In this work, a novel polyvinyl chloride (PVC)-coated glass slide system was advanced to capable long-term stabilization and microscopic conception of urine precipitation components. PVC films were functionalized with p-chlorobenzamidine (L) as photostabilizer to inhibit photodegradation induced via elongate exposure to UV light and microscope. The films photostability were systematically investigated employing FTIR, viscosity measurements, UV–Vis and FESEM analysis. At 365 nm, after 125 h of UV irradiation, the carbonyl index (Ico) for PVC+L films were increased to 0.13, compared with 0.18 of PVC, suggesting an essential reduction in oxidative degradation. The constant rate of photodegradation (kd) was reduced from 0.0021 s^-1 for pristine PVC to 0.0014 s^-1 for PVC+L sample, while the quantum yield of main-chain scission (Φcs) was decreased from 373×10¹³ to 884×10¹². Moreover, the PVC+L films preserved a higher viscosity-average molecular weight (Mv 260,000) contracted with the pristine PVC film after protracted irradiation, suggesting efficient inhibition of PVC chain scission. Functionally, at 295 nm, the PVC+L films appeared high (90 % transmittance) and cement clear microscopic conception of urine precipitation components. Cystine crystals, uric acid, calcium oxalate and triple phosphate, as well as amorphous materials, epithelial cells, kept optically distinguishable and morphologically intact for up to one year. These finds illustrate, for the first time, that photostabilized films can use as transparent, durable and chemically stable substrates for urine precipitation preservation, giving a low-cost and practical platform for routine microscopy, medical laboratory training and educational characteristics.

尿沉淀微观结构的长期维持一直是医学实验室教育和常规尿液分析的主要限制，因为传统的玻璃侧通常只允许样品稳定1-3小时。在这项工作中，一种新型聚氯乙烯（PVC）涂层玻璃载玻片系统被推进到能够长期稳定和尿液沉淀成分的微观概念。以对氯苯脒(L)为光稳定剂，对聚氯乙烯（PVC）薄膜进行了长时间紫外曝光和显微镜曝光，抑制了聚氯乙烯薄膜的光降解。采用红外光谱（FTIR）、粘度测试、紫外可见光谱（UV-Vis）和FESEM分析等方法对膜的光稳定性进行了系统的研究。在365 nm处，经过125 h的紫外照射，PVC+L薄膜的羰基指数（Ico）增加到0.13，而PVC的为0.18，表明氧化降解明显减少。恒定光降解速率（kd）从原始PVC的0.0021 s-1降低到PVC+L样品的0.0014 s-1，而主链断裂量子产率（Φcs）从373×1013降低到884×1012。此外，PVC+L膜在长时间辐照后保持了较高的粘度-平均分子量（Mv 26万）与原始PVC膜相比，表明有效抑制了PVC链断裂。在功能上，在295 nm处，PVC+L膜表现出较高的透光率（90%），并且水泥清晰的尿液沉淀成分的微观概念。胱氨酸晶体，尿酸，草酸钙和三磷酸，以及无定形材料，上皮细胞，保持光学可区分和形态完整长达一年。这些发现首次表明，光稳定膜可以作为透明、耐用和化学稳定的基底来保存尿液沉淀，为常规显微镜、医学实验室培训和教育提供了一个低成本和实用的平台。

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引用次数: 0

Fabrication and characterization of biocomposites from acetylated and bleached Agave atroverance L. fibers by grafting of styrene to enhance their thermomechanical, physicochemical, and morphological properties: A new approach 通过接枝苯乙烯提高龙舌兰纤维的热力学、物理化学和形态性能，制备和表征乙酰化和漂白龙舌兰纤维生物复合材料的新方法

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.sajce.2026.01.001

Md. Mahmudur Rahman , Md. Shamim Reza , Mohd. Maniruzzaman

Modification of natural fiber is very crucial to reduce their hydrophilic nature, in addition to enhancing their overall thermomechanical, physicochemical, and morphological properties. Thus, the modified natural fibers could be beneficially used to fabricate a new class of multifunctional biocomposites that should have a suitable agreement with the sustainable environmental development. Here, in this current work, acetylation and bleaching techniques were used to modify the extracted Agave atroverance L. fibers (AALF), and finally, a conspicuous method of modification, namely grafting of styrene monomer to fabricate multifunctional biopolymeric composites. While the grafting process was carried out onto the preliminary modified (both bleached and acetylated) fiber by using potassium persulphate (K₂S₂O₈) and ammonium persulphate (NH₄)₂S₂O₈ as initiator beneath the catalytic sway of ferrous sulphate (FeSO₄.7H₂O) in aqueous media to develop their overall strength, properties, and performances. Notably, the observed values of grafting yield were about 89.57 % and 94.86 % for bleached grafted and acetylated grafted AALF fiber, respectively. However, the raw, modified, and grafted biopolymeric specimens were characterized by conducting some state-of-the-art instruments like FTIR spectroscopy, SEM analysis, TGA, DTA, and DTG techniques. Additionally, the mechanical properties were investigated by conducting universal testing machine (UTM), which deals with tensile strength, Young’s modulus, and elongation/ductility. The obtained results suggested that the newly fabricated composites possess outstanding physicochemical, thermomechanical, and morphological properties due to the successful graft copolymerization. The maximum tensile strengths were observed around 179.39 and 173.10 MPa for the acetylated grafted and bleached grafted fibers. Thus, they could be beneficially used in various engineering/industrial sectors for sustainable environmental performance as a replacement for hazardous petroleum-based synthetic/conventional ones.

对天然纤维进行改性除了提高其整体的热力学、物理化学和形态性能外，还可以降低其亲水性。因此，改性天然纤维可用于制备与可持续环境发展相适应的新型多功能生物复合材料。本文首先对提取的龙舌兰纤维（Agave atroverance L.， AALF）进行了乙酰化和漂白改性，最后采用了一种引人注意的改性方法，即苯乙烯单体接枝制备多功能生物高分子复合材料。以过硫酸钾（K2S2O8）和过硫酸铵（NH4）2S2O8为引发剂，在硫酸亚铁（FeSO4.7H2O）的催化作用下，在水介质中进行了初步改性（漂白和乙酰化）纤维的接枝工艺，以提高纤维的整体强度、性能和性能。其中，漂白AALF纤维接枝率为89.57%，乙酰化AALF纤维接枝率为94.86%。然而，通过一些最先进的仪器，如FTIR光谱、SEM分析、TGA、DTA和DTG技术，对原始的、修饰的和接枝的生物聚合物样品进行了表征。此外，通过通用试验机（UTM）研究了机械性能，其中涉及抗拉强度，杨氏模量和伸长率/延展性。结果表明，由于接枝共聚的成功，新制备的复合材料具有优异的物理化学、热机械和形态性能。乙酰化接枝纤维和漂白接枝纤维的最大拉伸强度分别为179.39和173.10 MPa。因此，它们可以有益地用于各种工程/工业部门，以实现可持续的环境绩效，作为危险的石油基合成/常规石油的替代品。

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引用次数: 0

Assessment of microplastics in water and sediment from Megech river, major tributary to Lake Tana 塔纳湖的主要支流Megech河的水和沉积物中的微塑料评估

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.sajce.2025.12.014

Mequanent Esubalew Nigatu , Tewodros Nigatu Bitaw , Sisay Wondmagegn Molla , Abrham Bayeh Wassie

Ethiopia is the second largest importer of raw plastic materials in Central and Eastern Africa with fastest-growing plastic industry in the continent. Plastic pollution is a serious problem in the country and the government has started an awareness campaign for its reduction. This work is an initial attempt to evaluate the occurrence, abundance and characterization of microplastics (MPs) in shape, color and size from surface water and sediment of Megech River and its tributaries into Lake Tana, Ethiopia. As a result, the average abundance of MPs in surface water and sediment from 11 sampling sites were 0.55±0.31 items/L and 19.39 ± 11.91 items/Kg respectively. From the obtained total of 137 MP particles, the dominant shape, color and size were fragment (32.9%, 40.63%), transparent (30.17%, 29.69%), and <0.5 mm (47%, 47%) for surface water and sediment respectively. A significant difference in MP abundance was observed in the transition from upper rural to urban areas and lower rural, with higher concentrations distributed from urban tributaries to the main Megech River. This pattern is attributed to anthropogenic activities from Gondar city, which the River passes through. These results can be used to augment the current database of MPs pollution and provide useful references for further research.

埃塞俄比亚是中非和东非第二大塑料原料进口国，塑料工业在非洲大陆发展最快。塑料污染在这个国家是一个严重的问题，政府已经开始了一项减少塑料污染的宣传活动。这项工作是评估从Megech河及其支流进入埃塞俄比亚塔纳湖的地表水和沉积物中微塑料（MPs）的形状、颜色和大小的发生、丰度和特征的初步尝试。结果表明，11个采样点地表水和沉积物中MPs的平均丰度分别为0.55±0.31项/L和19.39±11.91项/Kg。在获得的137个MP颗粒中，地表水和沉积物的主要形状、颜色和大小分别为碎片（32.9%,40.63%）、透明（30.17%,29.69%）和<；0.5 mm（47%, 47%）。MP丰度在上游农村地区向城市地区和下游农村地区的过渡中存在显著差异，从城市支流到主要的Megech河的浓度较高。这种模式归因于贡达尔市的人为活动，贡达尔市是河流流经的地方。这些结果可用于扩充现有的MPs污染数据库，并为进一步的研究提供有用的参考。

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引用次数: 0

Predicting nanofiltration performance: A Runge-Kutta numerical framework for ion-specific rejection and flux-driven selectivity inversion in single and mixed salts 预测纳滤性能：单一和混合盐中离子特异性排斥和通量驱动选择性反演的龙格-库塔数值框架

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.sajce.2025.11.018

Rasha Amer Hajarat

Objectives

This study systematically investigates the synergistic effects of operational parameters, membrane properties, and ionic characteristics on ion rejection in nanofiltration (NF). The primary objectives are to (1) model ion transport mechanisms via the extended Nernst-Planck equation, (2) quantify rejection for key ions (K⁺, Br⁻, Cl⁻, SO₄²⁻, PO₄³⁻) across variable fluxes (10⁻⁷–10⁻⁵ m³/m²/s) and pore radii (0.4–5 nm), and (3) elucidate competitive ion interactions in multicomponent systems.

Methods

A novel numerical model integrating the extended Nernst-Planck equation with a fourth-order Runge-Kutta analysis was developed. The model was applied to both single (KBr, KCl, K₂SO₄, K₃PO₄) and mixed salt solutions to calculate ion concentrations and rejection rates under defined boundary conditions.

Results

The analysis yielded three critical advances: (i) Cation rejection (K⁺, up to 99 %) consistently exceeded anion rejection in single salts due to charge interactions. (ii) In mixtures, Br⁻ achieved anomalously high rejection (80 %) attributable to its optimal ionic radius and dynamic membrane charge effects. (iii) Competitive ion displacement induced negative rejection for Cl⁻ and PO₄³⁻, highlighting previously unreported flux-driven selectivity inversions.

Conclusion

This work establishes a predictive link between membrane design (pore size), operational flux, and ion-specific properties (charge, radius) across different environments. The findings demonstrate that tailored membrane optimization must account for competitive ion transport, advancing the rational design of high-efficiency NF systems for selective ion removal.

目的系统研究纳滤过程中操作参数、膜性能和离子特性对离子截留的协同效应。主要目标是：(1)通过扩展的能斯特-普朗克方程模拟离子传输机制；(2)量化关键离子（K +, Br⁻，Cl⁻，SO₄²⁻，PO₄³⁻）在不同通量（10⁻⁷-10⁻³/m²/s）和孔半径（0.4-5 nm）上的排斥；(3)阐明多组分系统中竞争离子的相互作用。方法建立了将扩展的能斯特-普朗克方程与四阶龙格-库塔分析相结合的新型数值模型。将该模型应用于单盐溶液（KBr、KCl、K₂SO₄、K₃PO₄）和混合盐溶液，计算在规定的边界条件下的离子浓度和截留率。结果该分析取得了三个关键进展：(i)由于电荷相互作用，阳离子排斥（K +，高达99%）在单一盐中始终超过阴离子排斥。（ii）在混合物中，由于其最佳离子半径和动态膜电荷效应，Br毒血症达到了异常高的抑制率（80%）。（iii）竞争性离子位移引起Cl - 4和PO - 4³的负反应，强调了以前未报道的通量驱动的选择性倒置。这项工作建立了不同环境下膜设计（孔径）、操作通量和离子特异性（电荷、半径）之间的预测联系。研究结果表明，量身定制的膜优化必须考虑竞争离子传输，推进高效纳滤系统的合理设计，以选择性去除离子。

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引用次数: 0

Sustainable corrosion inhibition of A36 steel in 1 M HCl using a citrus peel–surfactant bio-hybrid: Linking green chemistry with industrial-grade thermal performance 柑橘皮表面活性剂生物杂化对A36钢在1m HCl中的持续缓蚀作用：将绿色化学与工业级热工性能联系起来

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.sajce.2025.12.020

Abdul M. Sulaiman , Putu H Setyarini , Khairul Anam , Siti Norasmah Surip , Chin Wei Lai

In response to the growing demand for environmentally sustainable corrosion mitigation strategies in acidic industrial environments, a novel bio-hybrid corrosion inhibitor (CI30@CSE) is proposed, in which lauryl betaine (LB) in a commercial CI30 formulation is replaced by Citrus sinensis peel extract (CSE), a renewable agricultural waste-derived component. This work represents one of the first attempts to directly integrate a plant-based extract into an industrial-grade surfactant inhibitor system while preserving high inhibition performance. The hybrid system was systematically evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy, complemented by surface characterization (SEM, AFM) and spectroscopic analyses (FTIR, UV–Vis), together with density functional theory (DFT) and Monte Carlo simulations to elucidate adsorption behavior. CI30@CSE demonstrated a maximum inhibition efficiency of 97.88% at an optimal concentration of 400 ppm, outperforming the conventional CI30 inhibitor (93.76%), thereby confirming that substitution with a biomass-derived component can enhance protection without sacrificing industrial-level performance in 1 M HCl. Surface analysis via SEM and AFM confirmed the formation of denser, smoother, and more coherent protective films on A36 steel, while spectroscopic evidence and molecular simulations revealed strengthened adsorption stability and synergistic molecular interactions between the surfactant matrix and bioactive constituents of CSE. By valorizing citrus peel waste and partially replacing synthetic surfactants with a renewable bio-based alternative, this study contributes to circular chemical design and greener corrosion control strategies, offering a promising pathway toward high-performance, lower-toxicity corrosion inhibitors suitable for sustainable industrial applications.

为了响应在酸性工业环境中对环境可持续缓蚀剂日益增长的需求，提出了一种新型生物混合缓蚀剂（CI30@CSE），其中商用CI30配方中的月桂基甜菜碱（LB）被柑橘皮提取物（CSE）取代，这是一种可再生的农业废物衍生成分。这项工作是首次尝试将植物提取物直接整合到工业级表面活性剂抑制剂体系中，同时保持高抑制性能。利用动电位极化和电化学阻抗谱，结合表面表征（SEM， AFM）和光谱分析（FTIR, UV-Vis），以及密度泛函理论（DFT）和蒙特卡罗模拟来系统地评估混合体系的吸附行为。CI30@CSE在最佳浓度为400 ppm时的最大抑制效率为97.88%，优于传统的CI30抑制剂（93.76%），从而证实了用生物质衍生成分替代可以在不牺牲工业水平性能的情况下增强保护作用。SEM和AFM的表面分析证实了A36钢表面形成了更致密、更光滑、更连贯的保护膜，而光谱和分子模拟表明，表面活性剂基质与CSE生物活性成分之间的吸附稳定性和协同分子相互作用增强。本研究通过对柑橘皮废料进行增值处理，并用可再生的生物基替代品部分替代合成表面活性剂，为循环化学设计和更环保的腐蚀控制策略做出了贡献，为开发高性能、低毒的缓蚀剂提供了一条有希望的途径，适合可持续的工业应用。

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引用次数: 0

Modification starch of breadfruit (Artocarpus altilis) through esterification reaction with fatty acid as pesticides in controlled-release formulation 面包果淀粉与脂肪酸酯化改性为控释制剂农药

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.sajce.2025.11.020

Cut Fatimah Zuhra, Muhammad Zulham Efendi Sinaga, Rini Hardiyanti, Petronella Tambunan, Mariati Uly Artha, Zeli Amelia Putri, Esra Claudia, Wilza Fithri Azzahra

Technological advancements, particularly in agriculture, have now entered the stage of smart agrarian practices. One of the latest innovations in this practice is controlled-release pesticides. The use of hydrophobic materials can reduce the release rate of pesticides, which has long been an environmental issue. Starch properties can be modified according to needs by substituting the OH group with fatty acids through esterification reactions. In this study, breadfruit starch was modified with various fatty acids using a urea/NaOH solvent. The modified starch was successfully synthesized, as confirmed by FTIR, 1H NMR, TGA, SEM analyses, and also by examining the effects of the degree of substitution (DS), swelling power, and solubility (in water and DMSO). The results showed that starch modified with stearic acid achieved the best solubility value of 17.04 % and the lowest swelling power of 3.25 %, supported by data from other characterizations. The research concluded that the starch modified through esterification resulted in hydrophobic starch, and the method used was found to be optimal.

技术进步，特别是在农业方面，现在已经进入了智能农业实践的阶段。这种做法的最新创新之一是控释农药。疏水材料的使用可以降低农药的释放速度，这一直是一个环境问题。通过酯化反应用脂肪酸取代羟基，可以根据需要对淀粉的性质进行修饰。本研究采用尿素/氢氧化钠溶剂对面包果淀粉进行了不同脂肪酸的改性。通过FTIR、1H NMR、TGA、SEM分析，以及对取代度（DS）、溶胀力和溶解度（在水和DMSO中的溶解度）的影响，证实了改性淀粉的成功合成。结果表明，硬脂酸改性淀粉的溶解度最高，为17.04%，溶胀力最低，为3.25%。研究结果表明，通过酯化改性淀粉得到疏水淀粉，该方法是最优的。

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引用次数: 0

Recovery of fuel liquid from plastic waste using Ni/ZSM-5 catalyst by distillation bubble cap plate column 用Ni/ZSM-5催化剂蒸馏泡盖板塔回收废塑料燃料液

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.sajce.2025.12.019

Ramli Thahir , Agung Prabowo , Pintaka Kusumaningtyas , Muh. Irwan , Alwathan , Arief Adhiksana , Hanny Frans Sangian

The valorization of polypropylene (PP) plastic waste into high-value liquid fuels via catalytic pyrolysis represents a promising pathway toward sustainable waste-to-energy conversion. This study investigates the optimization of liquid fuel yield using a bifunctional Ni/ZSM-5 catalyst synthesized through impregnation. A total of 500 g of waste PP and 50 g of Ni/ZSM-5 (PP:Ni/ZSM-5 = 10:1) were processed in a stainless-steel fixed-bed semi-batch reactor over a temperature range of 420–580 °C. The evolved vapors were fractionated through a four-tray distillation bubble-cap column and condensed at ±5 °C. The Ni/ZSM-5 catalyst significantly enhanced cracking activity, enabling high liquid fuel recovery at lower operating temperatures. The best-performing temperature identified in this study was 480 °C, which yielded 77 wt.% liquid oil and 17 wt.% fuel gas whereas further heating beyond this point favored secondary cracking, converting liquid fractions into gaseous products. Fractional distillation revealed kerosene-range hydrocarbons in trays I–II and gasoline-range fractions in trays III–IV, indicating selective hydrocarbon distribution. These results demonstrate that Ni/ZSM-5 offers dual functionality for efficient cracking and aromatization, thereby improving product selectivity and energy recovery. The findings underscore the potential of catalytic pyrolysis as a scalable strategy for transforming plastic waste into alternative liquid transportation fuels while reducing environmental burden.

通过催化热解将聚丙烯（PP）塑料垃圾转化为高价值的液体燃料，是实现可持续废物能源转化的一条有希望的途径。采用浸渍法制备双功能Ni/ZSM-5催化剂，对液体燃料产率进行了优化研究。在不锈钢固定床半批式反应器中，在420-580℃的温度范围内处理500 g废PP和50 g Ni/ZSM-5 （PP:Ni/ZSM-5 = 10:1）。产生的蒸汽通过四盘蒸馏泡帽塔进行分馏，并在±5℃下冷凝。Ni/ZSM-5催化剂显著提高了裂解活性，在较低的工作温度下实现了较高的液体燃料回收率。本研究确定的最佳温度为480°C，产生77 wt.%的液态油和17 wt.%的燃料气，而进一步加热则有利于二次裂解，将液态馏分转化为气态产品。分馏发现1 - 2塔塔中有煤油段烃，3 - 4塔塔中有汽油段烃，说明烃类有选择性分布。这些结果表明，Ni/ZSM-5具有高效裂解和芳构化的双重功能，从而提高了产物的选择性和能量回收率。这些发现强调了催化热解作为一种可扩展的战略，将塑料废物转化为替代液体运输燃料，同时减少环境负担的潜力。

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引用次数: 0