Influence of process conditions on yields and kinetics of microwave assisted liquefaction reactions of olive pomace

Molecular Dynamics Simulation Study on Effect of Process Parameters on Coatings during Cold Spray Process

Ultrasonic welding is a solid-state joining process which uses ultrasonic vibration to join materials at relatively low temperatures. Ultrasonic powder consolidation is a derivative of the ultrasonic additive process which consolidates powder material into a dense solid block without melting. During ultrasonic powder consolidation process, metal powder under a compressive load is subjected to transverse ultrasonic vibrations resulting in a fully-dense consolidated product. While ultrasonic powder consolidation is employed in a wide variety of applications, the effect of critical process parameters on the bonding process of powder particles during consolidation is not clearly understood. This study uses a coupled thermo-mechanical finite element analysis technique to investigate the effect of critical process parameters including vibrational amplitude and base temperature on the stress, strain, and particle temperature distribution during the ultrasonic powder consolidation process. The study finds that during this process, the ultrasonically vibrating tool imparts cyclic vibratory shear stress on the particles. The simulation also revealed that the particle temperature just reaches the recrystallization point. Higher vibration amplitude imparted higher frictional heat on the particles, thereby aiding the consolidation process. The simulation study also showed indications of thermal softening and restricted grain boundary sliding during the ultrasonic powder consolidation process. The outcomes of this study can be used to further the industrial applications of ultrasonic powder consolidation process as well as other ultrasonic welding based processes.

The features of a drop-on-demand-based system developed for the manufacture of melt-based pharmaceuticals have been previously reported. In this paper, a supervisory control system, which is designed to ensure reproducible production of high quality of melt-based solid oral dosages, is presented. This control system enables the production of individual dosage forms with the desired critical quality attributes: amount of active ingredient and drug morphology by monitoring and controlling critical process parameters, such as drop size and product and process temperatures. The effects of these process parameters on the final product quality are investigated, and the properties of the produced dosage forms characterized using various techniques, such as Raman spectroscopy, optical microscopy, and dissolution testing. A crystallization temperature control strategy, including controlled temperature cycles, is presented to tailor the crystallization behavior of drug deposits and to achieve consistent drug morphology. This control strategy can be used to achieve the desired bioavailability of the drug by mitigating variations in the dissolution profiles. The supervisor control strategy enables the application of the drop-on-demand system to the production of individualized dosage required for personalized drug regimens.

The pretreatment of color filter wastewater towards biodegradable by Fresnel-lens-enhanced solar TiO2photocatalytic process was investigated. The experimental design of response surface methodology (RSM) was employed to assess the effect of critical process parameters (including initial pH, TiO2dosage, and reaction time) on pretreatment performance in terms of BOD5/COD, COD and TOC removal efficiency. Appropriate reaction conditions were established as an initial pH of 7.5, a TiO2dosage of 1.5 g/L with a reaction time of 3 h for increasing the BOD5/COD ratio to 0.15, which implied that the treated wastewater would be possibly biodegradable. Meanwhile, the efficiency of COD and TOC removals reached 32.9% and 24.4%, respectively. With the enhancement of Fresnel lens, the required reaction time for improving the biodegradability of wastewater to 0.15 was 1 h only. Moreover, the efficiency of COD and TOC removals was promoted to 37.4% and 25.8%, respectively. This could be mainly due to the concentrated effect of Fresnel lens for solar energy, including an increase of 2 times of solar irradiation and a raising of 15–20°C of wastewater temperature. Consequently, solar TiO2photocatalytic process with the use of a PMMA Fresnel lens could offer an economical and practical alternative for the pretreatment of industry wastewater containing diversified biorefractory pollutants with a high concentration of COD such as color filter wastewater.

As fossil fuel depletion and environmental pollution become increasingly severe, biodiesel has emerged as a promising renewable alternative to conventional diesel due to its biodegradability, low sulfur emissions, and high combustion efficiency. This paper provides a comprehensive review of the evolution of biodiesel feedstocks, major production technologies, and key factors influencing production efficiency and fuel quality. It traces the development of feedstocks from first-generation edible oils, second-generation non-edible oils and waste fats, to third-generation microalgal oils and fourth-generation biofuels based on synthetic biology, with a comparative analysis of their respective advantages and limitations. Various production technologies such as transesterification, direct esterification, supercritical alcohol methods, and enzyme-catalyzed transesterification are examined in terms of reaction mechanisms, process conditions, and applicability. The effects of critical process parameters including the alcohol-to-oil molar ratio, reaction time, and temperature on biodiesel yield and quality are discussed in detail. Particular attention is given to the role of catalysts, including both homogeneous and heterogeneous types, in enhancing conversion efficiency. In addition, life cycle assessment (LCA) is briefly considered to evaluate the environmental impact and sustainability of biodiesel production. This review serves as a valuable reference for improving biodiesel production technologies, advancing sustainable feedstock development, and promoting the commercial application of biodiesel.

Solar TiO2photocatalytic process assisted by a Fresnel lens was investigated for treating an azo dye wastewater of Acid Orange 10 (AO10). Response surface methodology (RSM) was employed to assess the effect of critical process parameters (including initial pH of wastewater, concentration of TiO2, and reaction time) on treatment performance in terms of COD and TOC degradation efficiency. Optimized reaction conditions based on the analysis of RSM were established under an initial pH of 6.0, a concentration of TiO2of 1 g/L, and a reaction time of 2 h for reaching a 90% COD and TOC degradation of AO10 wastewater. With the assistance of Fresnel lens, the TOC degradation rate of AO10 wastewater increased significantly from 0.606 h−1and 0.289 h−1to 1.477 h−1and 0.866 h−1in summer (June) season (UV280–400 nm nm: 39.9–44.8 W/m2) and winter (December) season (UV280–400 nm nm: 23.9–26.9 W/m2), respectively. This could be mainly due to the concentrating effect of Fresnel lens for solar energy, resulting in an increase of 2~2.5 times of solar light intensity and a raising heat irradiation in terms of 10~15 °C of wastewater temperature. These results revealed that solar energy could be concentrated effectively by using Fresnel lens and showed a significant promoting effect on the TiO2photocatalytic degradation of dye wastewater.

Decolorization of synthetic azo Reactive Red 120 (RR120) dye wastewater via UV/Fe+3 process was investigated. A preliminary study was conducted to understand the effect of various process variables like oxidant dose Fe+3 (0.25–2.75 mM)), initial dye concentration (100–200 mg/L), time (0–35 min), initial pH (1–11) on the decolorization of RR120. Response surface methodology (RSM) was employed to assess individual and interactive effects of critical process parameters on treatment performance in terms of colour removal efficiency. The photo-degradation of RR120 was investigated in a laboratory-scale batch photo-reactor equipped with low-pressure mercury lamp. Optimized process conditions for UV/Fe+3 treatment of RR120 suggested by RSM are Fe3+ = 2.35 mM, pH = 3.6, Initial dye concentration = 170 mg/L and reaction time = 55 min. Under these conditions, 92% colour removal was actually observed which is found to be very close to prediction given by fitted model. Treatment cost of UV/Fe+3 process was ~4 Rs/L.

Treatment of azo dye production wastewaters using Photo-Fenton-like advanced oxidation processes: Optimization by response surface methodology

Alternative to traditional olive pomace oil extraction systems: Microwave-assisted solvent extraction of oil from wet olive pomace

Applying quality by design principles to the small-scale preparation of the bone-targeting therapeutic radiopharmaceutical rhenium-188-HEDP

In this paper, the optimal process condition for microwave-assisted acid pretreatment of the corn stalk was investigated by Central-Composite design using Response Surface Method. Effects of microwave power, reaction time and acid concentration on reducing sugar yield were inspected. Also, analysis of corn stalk before and after the treatment was conducted with ultra depth microscope. The test result shows that, the sequence of factors is: acid concentration>reaction time>microwave power, and the interaction of microwave power and reaction time is significant; The optimal process condition is: microwave power 900W, reaction time 20min, acid concentration 2%, reducing sugar yield 230.9 mg/g. Through the microwave-assisted acid pretreatment, the fiber structures of the corn stalk were destroyed effectively, the treatment increases the degree of surface roughness, improves porosity, thus the rate of enzymolysis was enhanced. The p-value of regression model is 0.0002, and the p-value of Lack of fit is 0.1298, which indicates the regression equation is significant and the model fits well.

A microwave-assisted aromatic nucleophilic substitution reaction has been used to synthesize high molecular weight Poly(ArylEtherKetone)s (PAEKs) within very short reaction times and through a highly simplified process. The influence of different parameters, (namely the microwave power, solvent nature, or reaction time) on the polymer molecular weights were studied in order to optimize the polymerization conditions. The polymers thus obtained were characterized and compared with their analogues synthesized by conventional thermal polycondensation. This work underlines the potential of microwave-assisted aromatic polymer synthesis.

CFD–DEM–PBM coupled model development and validation of a 3D top-spray fluidized bed wet granulation process

Air gasification of high-ash solid waste in a pilot-scale downdraft gasifier: Experimental and numerical analysis

Environmental life cycle assessment of olive pomace utilization in Turkey