South African Journal of Chemical Engineering最新文献_第2页

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

Spherical and rod-shaped nanocellulose from filter paper waste: A comparative study of acid hydrolysis 从滤纸废料中提取球形和棒状纳米纤维素：酸水解的比较研究

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.sajce.2025.12.017

Zahrotul Istiqomah , Holilah , Didik Prasetyoko , Sri Sunarmi , Hendro Juwono , Agus Wedi Pratama , Mohd Saiful Asmal Rani , Dina Wahyu Indriani , Victor Feizal Knight , Mohd Nor Faiz Norrrahim

Filter paper waste represents a significant yet underutilized feedstock for producing nanocellulose, a high-value nanomaterial essential for bioplastics and nanocomposites due to its biodegradability and mechanical strength. Valorizing this laboratory byproduct supports circular economy principles by converting waste into functional materials. In this study, nanocellulose was successfully isolated from filter paper waste (FPW). Cellulose extracted from the FPW was converted into nanocrystalline cellulose (NCC) through acid hydrolysis using two inorganic acids (sulfuric and hydrochloric) and two organic acids (citric and formic). The results revealed that acid type significantly influences particle morphology: hydrolysis with inorganic acids yielded spherical NCC particles, while the organic acids produced thin rod-shaped NCC. The average particle diameters of NCC from sulfuric and hydrochloric acid were 42.08 nm and 53.14 nm, respectively. FPW-NCH exhibited the highest crystallinity (87.40%), while FPW-NCS showed the lowest thermal stability (degradation onset at 220 °C). These findings demonstrate that simple acid selection is a critical tool for tailoring nanocellulose properties for specific end-use requirements

滤纸废料是生产纳米纤维素的重要原料，但尚未得到充分利用。纳米纤维素是一种高价值的纳米材料，由于其可生物降解性和机械强度，对生物塑料和纳米复合材料至关重要。通过将废物转化为功能材料，该实验室副产品的增值支持循环经济原则。本研究成功地从滤纸废料（FPW）中分离出纳米纤维素。通过两种无机酸（硫酸和盐酸）和两种有机酸（柠檬酸和甲酸）的酸水解，将从FPW中提取的纤维素转化为纳米晶纤维素（NCC）。结果表明，酸类型显著影响颗粒形态：与无机酸水解得到球形NCC颗粒，而有机酸水解得到细棒状NCC颗粒。硫酸和盐酸中NCC的平均粒径分别为42.08 nm和53.14 nm。FPW-NCH的结晶度最高（87.40%），而FPW-NCS的热稳定性最低（在220℃时开始降解）。这些发现表明，简单的酸选择是定制纳米纤维素特性以满足特定最终用途要求的关键工具

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引用次数: 0

Regression analysis of corrosion inhibition of 42CrMo4 steel: a case study of acidified large Maradol leaf extract, kinetic, thermodynamics, adsorptions, and process parameter optimization 42CrMo4钢缓蚀性能的回归分析——以酸化大剂量马拉多叶提取物为例，动力学、热力学、吸附及工艺参数优化

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.sajce.2025.12.016

P.O. Oghenerukevwe , F Onyiriuka , T.F. Adepoju , S. Enomah , M.M. Mundu , N. Muhammed , N. Aisha , I.U. Usen , O.D. Oghenejabor

In the oil and gas sector, corrosion results in catastrophic failures, leaks, and equipment degradation that cause enormous financial losses (billions of dollars every year), serious safety risks (fires, explosions, exposure to poisonous H₂S), and significant environmental pollution (infection of land and water). Corrosive agents including H₂S, CO₂, water, and high temperatures cause asset integrity to be compromised, production to be disrupted by unplanned shutdowns, and maintenance, repair, and replacement costs to rise. Hence, this study attempt to minimize the corrosion rate (CR), and maximize the inhibition efficiency (IE) in oil and gas industry, response surface methodology and artificial neural network tools were used to study the effects of inhibition concentration, temperature, and time of the adsorption corrosion inhibition of 42CrMo4 steel in an acidified large Maradol Leaf Extract (LMLE) of green biomass. The phytochemicals analysis of the extract was examined, and the elemental composition of 42CrMo4 steel was ascertained. The weight loss method was computed via gravimetric analysis. The kinetic and thermodynamics parameters were carried out, while the adsorption isotherm was carried out via Langmuir, Frumkin, Temkin, and Flory-Huggin isotherms.

Results shows that the compositions of the steel was majorly iron (Fe) contained 97.26%. The phytochemical analysis of the extract indicated the presence of flavonoids, phenols, saponins, alkaloids, tannins, steroids, and terpenoids found in organic biomass extract. Process modeling and optimization by central composite rotatable design (in RSM) shows a validated average minimum CR of 12.60 mm/yr and the optimum IE of 91.40%, while genetic algorithms (in ANN) validated an average minimum CR of 9.70 mm/yr and the optimum IE of 94.12%, respectively. From isotherms study, Langmuir isotherm model was found best fitted and described the corrosion inhibition mechanism of 42CrMo4 steel. Based on thermodynamic data, the negative ∆G_ads from - 73.42 to - 140.42 kJ/mol connote chemisorptions adsorptions.

The study concluded that the extract of large Maradol leaf when treated with 15% hydrochloric acid could serve inhibitor for treatment of 42CrMo4 steel corrosion in an oil well environment.

在油气行业，腐蚀会导致灾难性的故障、泄漏和设备老化，造成巨大的经济损失（每年数十亿美元），严重的安全风险（火灾、爆炸、有毒H2S暴露）以及严重的环境污染（土地和水的感染）。包括H2S、CO2、水和高温在内的腐蚀性物质会破坏资产的完整性，导致生产因计划外停产而中断，并导致维护、维修和更换成本上升。因此，本研究试图在石油和天然气工业中最小化腐蚀速率（CR）和最大化缓蚀效率（IE），采用响应面法和人工神经网络工具研究了缓蚀浓度、温度和时间对42CrMo4钢在酸化的绿色生物质大剂量马拉多叶提取物（LMLE）中吸附缓蚀的影响。对提取液进行了植物化学分析，确定了42CrMo4钢的元素组成。通过重量分析计算出减重方法。采用Langmuir、Frumkin、Temkin和Flory-Huggin等温线进行吸附等温线分析。结果表明，该钢的主要成分为铁（Fe），含铁量为97.26%。植物化学分析表明，有机生物质提取物中含有黄酮类、酚类、皂苷类、生物碱类、单宁类、类固醇类和萜类化合物。采用中心复合可旋转设计（RSM）的工艺建模和优化结果表明，平均最小CR为12.60 mm/yr，最优IE为91.40%，遗传算法（ANN）的平均最小CR为9.70 mm/yr，最优IE为94.12%。等温线研究发现，Langmuir等温线模型最适合描述42CrMo4钢的缓蚀机理。根据热力学数据，负的∆Gads在- 73.42 ~ - 140.42 kJ/mol范围内表示化学吸附。研究结果表明，用15%盐酸处理的大毛拉多尔叶提取物可作为油井环境中42CrMo4钢腐蚀的缓蚀剂。

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引用次数: 0

UV light-driven photocatalytic degradation of methylene blue with β-Ga2O3 nanoparticles conjugated to nanocellulose extracted from a biowaste fibre 从生物废料纤维中提取的纳米纤维素偶联β-Ga2O3纳米颗粒紫外光驱动光催化降解亚甲基蓝

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-12-22 DOI: 10.1016/j.sajce.2025.12.013

Maphai Maake, Irvin Noel Booysen, Allen Mambanda

β-Ga₂O₃ NPs were synthesised hydrothermally and annealed at 1000 °C. Citrate-capped nanocellulose fibres (CNCFs) were extracted from Azanza Garckeana fibres through sequential hydrolysis in 4.1 % citric acid, which had been diluted from a lemon concentrate (pH < 1.5) and 2 % NaOH. The best performing photocatalyst comprising a composite of β-Ga₂O₃ NPs dispersed onto CNCFs with a 20 % mass (β-Ga₂O₃/20 % CNCFs) was used for the degradation of methylene blue (MB) at pH 9 and under a 365 nm ultraviolet light irradiation at a radiance of 106 mW cm⁻². The mean rate of MB degradation in the presence of β-Ga₂O₃/20 % CNCFs was 14.1 (±0.5) x 10⁻³ min^−1, in 1.56 mM MB solution, and this was 2 times higher than for β-Ga₂O_3, which had a rate constant of 7.8 (±0.4) x 10⁻³ min⁻¹. The rates for both catalysts were slightly lower in a river water spiked at the same level. The β-Ga₂O₃/20 % CNCFs NPs demonstrated good reusability and stability, allowing for up to 4 cycles, for which the degradation efficiency decreased only by <20 %. Radical capture with specific scavengers suggested positively charged holes (h⁺), OH^•, and O₂^•- as active species responsible for the photocatalytic redox degradation of MB. Mass spectra of intermittently sampled mixtures from the degradation process revealed the formation of sulphonated amino-phenyl aldehydes and amino-polyphenols as reaction intermediates. These intermediates are colourless, more environmentally benign. A 77 % reduction in the chemical oxygen demand (COD) of a 1.56 mM MB spiked solution upon photodegradation for 3 h, together with the mass spectral data after the reaction, suggested the partial carbon mineralisation of MB to form water and dissolved carbon dioxide.

采用水热法合成β-Ga2O3纳米粒子，并在1000℃下退火。柠檬酸覆盖纳米纤维素纤维（CNCFs）从Azanza Garckeana纤维中通过4.1%柠檬酸的顺序水解提取，柠檬酸从柠檬浓缩液（pH < 1.5）和2% NaOH中稀释。由分散在质量为20%的CNCFs上的β-Ga2O3纳米粒子组成的复合光催化剂（β-Ga2O3/ 20% CNCFs）在pH为9、辐射强度为106 mW cm - 2的365 nm紫外光照射下，用于降解亚甲基蓝（MB）。在1.56 mM MB溶液中，β-Ga2O3/ 20% cncf存在时，MB的平均降解速率为14.1（±0.5）× 10−3 min−1，是β-Ga2O3的2倍，β-Ga2O3的降解速率常数为7.8（±0.4）× 10−3 min−1。两种催化剂的反应速率在同一水平的河水中稍低。β- ga2o3 / 20% CNCFs NPs表现出良好的可重复使用性和稳定性，允许多达4次循环，降解效率仅下降了20%。特定清除剂的自由基捕获表明，带正电的空穴（h+）、OH•和O2•-是光催化氧化还原降解MB的活性物质。降解过程中间歇采样的混合物的质谱显示，磺化氨基苯基醛和氨基多酚作为反应中间体。这些中间体无色，更环保。1.56 mM MB加标溶液在光降解3小时后，化学需氧量（COD）降低77%，结合反应后的质谱数据，表明MB的部分碳矿化形成水和溶解的二氧化碳。

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引用次数: 0

Predictive ANN analysis of hydrothermal and entropy behavior of corrugated heat exchanger featuring tetra-hybrid nanofluid 四杂化纳米流体波纹换热器热液和熵行为的预测神经网络分析

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-12-18 DOI: 10.1016/j.sajce.2025.12.012

Salma Jahan, Rehena Nasrin

Compact energy systems need working fluids with exceptional heat transfer (HT) properties for effective thermal management. Though their behavior in complex microchannels is little studied, tetra-hybrid nanofluids of four nanoparticles show great potential. This research employs numerical analysis to investigate the thermo-hydraulic characteristics of a tetra-hybrid nanofluid comprising multi-walled carbon nanotubes (MWCNT), boron nitride (BN), nanodiamond (ND), and graphene (G) in a sinusoidal wavy crossflow microchannel heat exchanger (SWCFMCHE). The governing equations were solved using Galerkin’s weighted residual finite element method (FEM). Furthermore, an artificial neural network (ANN) model was developed to accurately predict key performance parameters such as Nusselt number (Nu), efficiency (ε), and performance index (η). The wavy microchannel heat exchanger’s heat transfer rate (HTR) was assessed by varying several important factors, such as the nanoparticle solid-volume fraction (

ϕ

= 0.01–2 %), number of wave cycles (NWC = 0–3), inlet velocity (

u_{i}

= 0.0038–0.2479 m/s), and heat exchanger (HE) material (copper, aluminum, and stainless steel). For comparison, several heat transferring fluids, including water and water-based hybrid, ternary, and tetra-hybrid nanofluids, were also investigated. Results show that tetra-hybrid nanofluid offers the highest HTR among all tested fluids at equal concentration ratios,

ϕ

= 2 %, particle diameter (dp) = 1 nm, nanoparticles shape factor (

n

) = 16.1576, and NWC = 2. In case of tetra-hybrid nanofluid, the highest

N u

= 16.749 is achieved at

u_{i} = 0.2479

m/s, showing enhancements of 19 %, 13 %, 9 %, and 4 % compared to all other heat transferring fluids. The highest efficiency (71.2 %) and performance index (601 × 10³) are observed for the tetra hybrid nanofluid at

u_{i} = 0.0038

m/s. The ANN model accurately predicts thermo-hydraulic parameters. Overall, this integrated numerical and data-driven framework offers new insights into nanoparticle synergy and geometric enhancement, making a significant contribution to the design of efficient heat exchangers (HEs).

紧凑的能源系统需要具有特殊传热（HT）性能的工作流体来进行有效的热管理。虽然它们在复杂微通道中的行为研究很少，但四种纳米颗粒的四杂化纳米流体显示出巨大的潜力。本研究采用数值分析方法研究了由多壁碳纳米管（MWCNT）、氮化硼（BN）、纳米金刚石（ND）和石墨烯(G)组成的四杂化纳米流体在正弦波横流微通道换热器（SWCFMCHE）中的热水力特性。采用Galerkin加权余量有限元法求解控制方程。此外，还建立了人工神经网络（ANN）模型，以准确预测Nusselt数（Nu）、效率（ε）和性能指标（η）等关键性能参数。波浪型微通道换热器的换热率（HTR）是通过改变几个重要因素来评估的，如纳米颗粒固体体积分数（φ = 0.01 - 2%）、波浪循环次数（NWC = 0-3）、入口速度（ui = 0.0038-0.2479 m/s）和换热器（HE）材料（铜、铝和不锈钢）。为了进行比较，还研究了几种传热流体，包括水和水基杂化、三元和四杂化纳米流体。结果表明，在相同浓度比下，四混合纳米流体的HTR最高，其中φ = 2%，粒径(dp) = 1 nm，形状因子(n) = 16.1576, NWC = 2。在四杂化纳米流体中，ui=0.2479m/s时Nu = 16.749最高，与其他传热流体相比分别提高了19%、13%、9%和4%。在ui=0.0038 m/s时，四杂纳米流体的效率最高（71.2%），性能指标最高（601 × 10³）。人工神经网络模型能准确预测热工参数。总体而言，这种集成的数值和数据驱动框架为纳米颗粒协同作用和几何增强提供了新的见解，为高效热交换器（HEs）的设计做出了重大贡献。

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引用次数: 0