South African Journal of Chemical Engineering最新文献_第8页

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

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01

引用次数: 0

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01

引用次数: 0

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01

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

Heat transfer enhancement in fractional Brinkman nanofluids: Effects of thermal and nanoparticle geometry 分数布林克曼纳米流体的传热增强：热和纳米颗粒几何形状的影响

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-12-17 DOI: 10.1016/j.sajce.2025.12.011

Muhammad Irfan Qadir , Ali B.M. Ali , Hakim AL Garalleh , Usman Majeed , Faheem ul Islam , Ali Raza , Sami Ullah Khan , Nodira Nazarova , Manish Gupta , M. Waqas , M. Ijaz Khan

This communication aims to develop a fractional mathematical model for flow of generalized Brinkman fluid with utilization of nanoparticles over vertically heated plate. A suspension of titanium oxide

(T i O_{2})

and molybdenum disulfide

(M o S_{2})

with water

(H_{2} O

) base fluid is considered to evaluates the heat transfer enhancement. Thermal properties of nanoparticles is presented. The problem is entertained with amplification of slip features. After formulating the governing equation, a novel fractional scheme namely Prabhakar technique is implemented. The integration framework is facilitated with famous Laplace technique. Physical interpretation of results has been revealed with different values of parameters. It is observed that velocity profile reduces due to Brinkman fluid parameter. Interaction of velocity slip parameter leads to decrement of velocity profile. Moreover, change in nanoparticles volume fraction leads to enhancement of temperature profile.

本文旨在建立一个利用纳米颗粒在垂直加热板上流动的广义布林克曼流体的分数数学模型。用二氧化钛（TiO2）和二硫化钼（MoS2）与水（H2O）基液的悬浮液来评价传热增强效果。介绍了纳米颗粒的热性能。用滑移特征的放大来讨论这个问题。在建立控制方程后，实现了一种新的分数格式，即Prabhakar技术。利用著名的拉普拉斯技术简化了积分框架。揭示了不同参数值对结果的物理解释。观察到由于布林克曼流体参数的影响，速度剖面减小。速度滑移参数的相互作用导致速度剖面的衰减。此外，纳米颗粒体积分数的变化导致温度分布的增强。

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引用次数: 0

Development of MnO2/γ-Al2O3 catalysts for catalytic ozonation of phenolic wastewater MnO2/γ-Al2O3催化臭氧化处理含酚废水的研究

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-12-14 DOI: 10.1016/j.sajce.2025.12.009

Made Ayu Saraswati , Wibawa Hendra Saputera , Edlyn Lafina , Dwiwahju Sasongko

Phenolic compounds in industrial wastewater pose significant environmental and health risks due to their toxicity and persistence. This study develops MnO₂/γ-Al₂O₃ catalysts for catalytic ozonation and examines how HNO₃ surface modification and calcination temperature influence γ-Al₂O₃ properties and catalytic performance. The optimized catalyst (MA-25-700-4 %) achieved the highest phenol degradation efficiency (92.23 %) with the fastest reaction rate (k = 0.0450 min⁻¹), outperforming catalysts prepared from unmodified commercial γ-Al₂O₃. Enhanced surface area, mesoporosity, and well-dispersed MnOx species promoted efficient ozone activation through the Mn(IV)/Mn(III) redox cycle, facilitating •OH radical generation. The catalyst also demonstrated good reusability over three catalytic ozonation cycles, with only a moderate decrease in reaction rate (k, reduced by ∼31 % from cycle 1 to cycle 3), confirming structural stability and sustained catalytic activity. These findings highlight the importance of controlled support modification and optimized Mn loading in engineering high-performance MnO₂/γ-Al₂O₃ catalysts for advanced treatment of phenolic wastewater.

工业废水中的酚类化合物因其毒性和持久性而对环境和健康构成重大风险。研究了MnO₂/γ-Al₂O₃催化臭氧化催化剂，研究了HNO₃表面改性和煅烧温度对γ-Al₂O₃性质和催化性能的影响。优化后的催化剂（MA-25-700-4 %）的苯酚降解效率最高（92.23%），反应速度最快（k = 0.0450 min⁻），优于未改性的商用γ-Al₂O₃制备的催化剂。增强的表面积、介孔率和分散良好的MnOx物种通过Mn(IV)/Mn（III）氧化还原循环促进了臭氧的有效活化，促进了•OH自由基的生成。该催化剂在三个催化臭氧化循环中也表现出良好的可重复使用性，反应速率仅适度降低（k，从循环1到循环3降低了~ 31%），证实了结构稳定性和持续的催化活性。这些发现强调了控制载体修饰和优化Mn负载对于工程高性能MnO2/γ-Al2O3催化剂深度处理酚类废水的重要性。

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引用次数: 0

Process design for the continuous production of α- and γ-mangostin from mangosteen pericarp with integrated solvent recovery 以山竹果皮为原料连续生产α-和γ-山竹苷的工艺设计

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-12-09 DOI: 10.1016/j.sajce.2025.12.008

Preuk Tangpromphan , Amaraporn Kaewchada , Attasak Jaree

Mangosteen pericarp, a major agricultural by-product, is a rich source of xanthones, including α- and γ-mangostin, which possess significant anticancer and anti-inflammatory properties. This study details the continuous production process for these bioactive compounds, focusing on material and energy balance, performance parameters, and preliminary economic feasibility. The process includes material pretreatment, extraction, and separation using a three-zone simulated moving bed (TZ-SMB) system.

Extraction experiments were optimized to model the yield of α-mangostin based on temperature and solvent (acetonitrile) concentration. The optimal extraction conditions were found to be 40 °C and 65 % v/v acetonitrile, achieving a maximum yield of 70.49 mg/g of dried pericarp. For the separation process, models based on triangle theory were developed to determine the maximum feed flow rate for the TZ-SMB system while ensuring at least 98 % relative purity for both compounds.

A block flow diagram was used for material and energy balance calculations, performed in MATLAB. The wet mangosteen pericarp feed rate was varied to achieve the target xanthone concentrations required for the TZ-SMB design. At the optimal solvent recycle ratio of 90 %, the system demonstrated a daily production capacity of 477.65 mg for α-mangostin and 140.76 mg for γ-mangostin, with a favorable benefit-to-cost ratio. The economic analysis confirms the process's profitability, especially with solvent recovery. This work provides a foundational preliminary design, supporting strategic decision-making and laying the groundwork for more detailed process design using simulation software.

山竹果皮是一种重要的农业副产品，含有丰富的山酮，包括α-和γ-山竹苷，具有显著的抗癌和抗炎作用。本研究详细介绍了这些生物活性化合物的连续生产过程，重点关注物质和能量平衡、性能参数和初步的经济可行性。该过程包括使用三区模拟移动床（TZ-SMB）系统进行材料预处理、提取和分离。以提取温度和溶剂（乙腈）浓度为参数，对α-山竹苷提取率进行优化。最佳提取条件为40°C、65% v/v乙腈，最大得率为70.49 mg/g。对于分离过程，建立了基于三角理论的模型，以确定TZ-SMB系统的最大进料流量，同时确保两种化合物的相对纯度至少为98%。在MATLAB中使用块流程图进行物质和能量平衡计算。通过改变湿山竹果皮的进料速率来达到z - smb设计所需的靶山酮浓度。在溶剂回收率为90%的条件下，该体系日产量分别为477.65 mg α-山竹苷和140.76 mg γ-山竹苷，具有较好的经济效益。经济分析证实了该工艺的盈利能力，特别是溶剂回收。这项工作提供了一个基本的初步设计，支持战略决策，并为使用仿真软件进行更详细的工艺设计奠定了基础。

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引用次数: 0

Enhancing cooling tower efficiency using ammonium persulfate (APS) as a thermal performance additive 使用过硫酸铵（APS）作为热性能添加剂提高冷却塔效率

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2025-12-08 DOI: 10.1016/j.sajce.2025.12.007

Ekhlas A. Salman , Nawar S. Rasheed , Shaymaa A. Ahmed , Hasan F. Makki

This study examines the influence of Ammonium Persulfate (APS) solutions at varying concentrations (0.1, 0.5, 1, and 2 mol/L) on the thermal performance of counterflow cooling towers. It focuses on their effects on outlet water temperature, air heat gain, humidity variation along the tower height, and overall thermal range. Experimental findings demonstrate that the APS solution markedly enhances cooling performance by expanding the cooling range by up to 25 %, lowering the approach temperature by as much as 3C, and boosting thermal efficiency. APS shows superior performance under higher inlet water temperatures and variable environmental conditions. At a concentration of 1 mol/L, particularly within the temperature range of 50–45C, the efficiency increases by 17.6 %, rising from 72.81 % to 85.69 %. The enhancement in heat transfer is attributed to three synergistic mechanisms: increased evaporation due to reduced surface tension, enhanced latent heat absorption through mild endothermic decomposition, and the strong agreement between a physics-based heat and mass transfer model and the experimental data. These results confirm the viability of APS as an efficient, practical, and scalable additive for optimizing cooling tower performance across a wide range of operating conditions.

本研究考察了不同浓度的过硫酸铵（APS）溶液（0.1、0.5、1和2 mol/L）对逆流冷却塔热性能的影响。重点研究了它们对出水温度、空气热增益、塔高沿线湿度变化和整体热范围的影响。实验结果表明，APS解决方案显著提高了冷却性能，将冷却范围扩大了25%，将接近温度降低了3℃，并提高了热效率。APS在较高的进水温度和多变的环境条件下表现出优越的性能。在浓度为1 mol/L时，特别是在50 - 45℃的温度范围内，效率提高了17.6%，从72.81%上升到85.69%。传热的增强可归因于三个协同机制：由于表面张力降低而增加的蒸发，通过温和吸热分解增强的潜热吸收，以及基于物理的传热传质模型与实验数据之间的强烈一致性。这些结果证实了APS作为一种高效、实用、可扩展的添加剂在各种操作条件下优化冷却塔性能的可行性。

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引用次数: 0