Effect Of Pretreatment Process Research Articles

Effect of pretreatment process on the performance of Ni-Co-Al2O3(sol) nanocomposite coatings via electro-brush plating on steel substrate

Effect of pretreatment process on the performance of Ni-Co-Al2O3(sol) nanocomposite coatings via electro-brush plating on steel substrate

Effect of pretreatment process on microstructure and mechanical properties in Inconel 718 alloy

The residual stress reduction, the precipitation behavior of γ" phase and the evolution of mechanical properties of Inconel 718 alloy in solid solution annealed with different pretreatment were investigated. The results show that the pretreatment process can effectively reduce the quenching residual stresses. With the increase of pretreatment temperature from 680 °C to 720 °C, the residual stress reduction rate increased from 52% to 65%, and the corresponding stress relaxation mechanism changed from dislocation slip dominated to both dislocation slip and grain boundary migration. Meanwhile, the pretreatment process promotes the nucleation and precipitation of the γ" phase, which is uniformly nucleated and always consistent with the matrix. The yield strength of the pretreated samples was slightly increased compared to the purely aged state, with an extreme value of 5.1%. The increase in strength is mainly attributed to the coherent hardening effect associated with the morphology and distribution of the γ" phase.

Synergistic effects of heteropoly acids and sulfolane on fractionation and utilization of willow

Efficient pretreatment to decrease the recalcitrance of lignocellulosic biomass is considered to be an essential precondition for lignocellulosic valorization. In this study, the heteropoly acids (i.e., phosphotungstic acid, silicotungstic acid and phosphomolybdic acid) assisted sulfolane organosolv pretreatment was developed to reduce the recalcitrance of willow ( Salix matsudana cv. Zhuliu ) for effective saccharify cation and the subsequent lignin valorization. The pretreatment notably increased the accessibility of cellulose with a high glucose yield of 94.77%. The 75.60% of lignin was recovered from the willow with silicotungstic acid assisted sulfolane organosolv pretreatment at 150 °C for 1.5 h. In addition, the recovered lignin had high purity (∼98%), moderate molecular weight (3378–3585 g/mol), low polydispersity (∼2.0) and good antioxidant properties (the RSI value was 1.18). Lignin nanospheres (LNSs) with different morphologies were prepared by separating lignin, which increased the potential application of lignin. Overall, the heteropoly acids assisted sulfolane pretreatment proved to be a promising approach for enzymatic hydrolysis of cellulose and lignin valorization. • Effects of pretreatment process are improved compared with the condition without catalyst. • Glucan digestibility reach to 94.7%. • Lignin reaches a purity of 98.0% and an extraction ratio of 75.6%. • Lignin has better antioxidant activity than commercial antioxidant butylated hydroxytoluene (BHT). • Lignin nanospheres (LNSs) with different morphologies were prepared, which increased the potential application of lignin.

Effect of Pretreatment Process on Microstructure and Mechanical Properties in Inconel 718 Alloy

Effect of Pretreatment Process on Microstructure and Mechanical Properties in Inconel 718 Alloy

Fabrication of zeolite coatings onto stainless-steel capillary tubes for supercritical hydrocarbon cracking

In tubular reactors, the pressure drop can be decreased, and the heat transfer can be enhanced by coating the catalyst on its inner-wall when compared with the performance of fixed-bed types. This study focused on preparing catalyst coatings in capillary tubes for hydrocarbon cracking. The effect of pretreatment processes on the physicochemical properties of the catalyst was studied, and the influence was negligible. In addition, the preparation process was optimized by adjusting the coating method, binder types and contents. The coating prepared using 10 wt% organic binder with an interval coating method showed optimal adhesion. The mass loss was 3.92% after thermal shock and ultrasonic oscillation treatment. During n-dodecane cracking, the gas production rate (GPR) without coating was 8.27%, while that were 31.62% and 65.42% with ZSM-5 and MFI coatings, respectively. Above all, the coatings inhibited coke formation so that the reaction could be continuously performed at 600 °C.

Effect of Pretreatment Process on the Adhesion and Corrosion Resistance of Nickel-Boron Coatings Deposited on 8620H Alloy Steel

Effect of Pretreatment Process on the Adhesion and Corrosion Resistance of Nickel-Boron Coatings Deposited on 8620H Alloy Steel

Fabrication of ionic polymer-metal composite actuators with durable and quality-enhanced sputtered electrodes

In this study, a sputter-based procedure was developed for fabricating IPMC’s wrinkled metal stack electrodes. Micro-texturing pre-treatments such as sandblasting and manual sandpapering followed by plasma treatment were individually used to wrinkle the surfaces of the Nafion membranes and to enhance the adhesion between membranes and sputtered electrodes. It was analytically indicated that increasing surface roughness increases the endurance of electrodes against the tensile stress. The effects of pre-treatment processes on the mechanical properties of the Nafion membranes and strength of the electrodes were investigated by means of the tensile test and theoretically discussed. The results show that micro-texturing of the surface of the membrane, resulting in a decrease in the elastic modulus and an increase in the yield stress. The surface roughening by sandblasting technique followed by plasma treatment before the sputtering process resulted in high-quality wrinkled electrodes, which can easily tolerate tensile strain caused by volume expansion of Nafion or IPMC bending, and significantly reduce cracks and prevent electrodes peeling off phenomenon. The proposed IPMC manufacturing approach is short, low cost, controllable, and reproducible. Investigation of the electromechanical performance of the IPMC actuator exhibits an average bending deformation of 115° and an average blocking force of 75 mN under a driving voltage of 5 V.

Effect of Pretreatment Process on the Adhesion and Corrosion Resistance of Chromium-Carbon Coatings Deposited on Copper Substrates

Effect of Pretreatment Process on the Adhesion and Corrosion Resistance of Chromium-Carbon Coatings Deposited on Copper Substrates

Effect of Pretreatment Process on Scale Formation in the Re-Boiler Section of Monoethylene Glycol Regeneration Plant

Monoethylene glycol (MEG) regeneration plants often use pretreatment vessels to precipitate divalent cations, such as Fe2+, Ca2+, and Mg2+, in order to avoid or reduce fouling in downstream reboilers and heat exchangers. This pretreatment process operates under alkaline conditions and moderate temperatures (~ 80 °C) to accelerate the formation of low-solubility divalent salts. The objective of the present research was to determine whether the pretreatment process could be minimized, without negatively impacts on the MEG regeneration process from to the formation of scale on the heater bundle in the presence of low concentrations of divalent cations in the rich MEG stream. Scale formation was analyzed under MEG regeneration process conditions using a dynamic scale loop (DSL) test and verification experiments were performed in a MEG regeneration and reclamation pilot plant, both with and without pretreatment conditions. The scaling tendencies of several rich MEG–brine mixtures were evaluated at different pH pretreatment levels and dissolved CO2 concentrations. An evaluation temperature of 180 °C was chosen to match the skin temperature of the reboiler heater bundle during the MEG regeneration process. The experiments of pH 7.24 showed high amounts of precipitation scale within the reboiler due to high remaining concentrations of mineral ions. In addition, small concentrations of calcium and magnesium ions led to the precipitation of calcite, dolomite, and magnesium hydroxide on the reboiler bundle and within associated filtered outputs even when a pretreatment vessel was present. These results were confirmed by the differential pressure build-up and Scanning Electron Microscopy analyses for each experimental condition. Another interesting finding is that pH increased within the reboiler due to CO2 gas boiling off at high operating temperatures, thus contributing to increased alkalinity levels, which in turn promoted scale formation. These results indicate that pretreatment should not be reduced, even with divalent ion concentrations as low as ~ 5 ppm TDS, due to the harsh conditions within the reboiler heater bundle.

Effect of pretreatment processes on physicochemical properties of hydroxyapatite synthesized from Puntius conchonius fish scales

The current study emphasizes on the novel idea of synthesizing hydroxyapatite (HAp) from Puntius conchonius fish scales’ bio-waste and study the effect of acid, alkali and acid–alkali pretreatments on its physicochemical properties. Material characterization is carried out to study the physicochemical properties of the synthesized HAp using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy energy dispersive X-ray spectroscopy (SEM-EDX) and transmission electron microscopy (TEM) analysis. FTIR and XRD plots show peaks corresponding to natural bone apatite which confirms the formation of HAp. TG analysis shows a maximum weight loss of 2.28% indicating high thermal stability of HAp beyond 800 $$^{\circ }$$ C. SEM micrographs illustrate highly porous morphology with interconnected pores. EDX analysis of the HAp exhibits close proximity of the calcium/phosphorous (Ca/P) ratio to natural bone apatite. TEM micrographs show the formation of polycrystalline HAp particles with size ranging from $$38\pm 1.54$$ to $$219\pm 5.88~\hbox {nm}$$ . A comparative study on the physicochemical properties of HAp synthesized using three different pretreatment processes is performed. Results reveal that HAp synthesized from acid-treated fish scales show highest yield percentage, better thermal stability and highly porous morphology with a particle size of $$38 \pm 1.54~\hbox {nm}$$ . Thus, HAp synthesized from acid-treated fish scales can be a promising candidate for the development of porous bone scaffolds.

Effect of Pretreatment Process on the Metal-Porcelain Bonding Mechanism and Properties of CoCr Alloy Dental Crown and Bridge Manufactured by SLM

This paper aims to investigate the influential mechanism of grinding and sand blasting pretreatment of CoCr alloy manufactured by SLM (selective laser melting) process on the metal-porcelain bonding of the restorations, and then provides references for SLM manufacturing CoCr alloy dental crown and bridge restorations with good mechanical properties. Three groups of CoCr alloy substrates were manufactured by SLM process with optimal parameters. The samples were subjected to different grinding and sand blasting pretreatment, and the porcelain sintering was carried out with the same parameters. The samples of different groups were analyzed by three-point bending test, roughness test, SEM and EDS. Results show that the metal-porcelain bonding strength of samples in group a with grinding and sand blasting is 36.79±0.49 MPa, which is obviously higher than those of group b with no grinding but sand blasting and group c with only grinding. The average metal-porcelain bonding strength of the three group samples is higher than the ISO9693: 1999 standard minimum 25 MPa. The metal-porcelain bonding effect of group a and c is better than that of group b, and the element diffusion on metal-porcelain interface is observed in all three groups. The results also show that there are significant differences among the three groups on residues and element distribution of metal-porcelain peeling surface. The final conclusion is that the surface roughness obtained by the pretreatment of sand blasting and grinding can ensure the strong chemical combination of metal and porcelain and considerable mechanical properties combination, which can improve the performance of metal-porcelain restorations manufactured by SLM.

Effect of pre-treatment processes on physicochemical aspects of vacuum-fried banana chips

The objective of this study was to investigate the influence of various pre-treatments on the physicochemical and sensory characteristics of vacuum-fried (VF) banana chips (120°C, 41.3 kPa) and consequently compare them to atmospheric-fried (AF) banana chips (170°C). Pre-treatments comprised of osmotic dehydration with sucrose solution (ODSu), osmotic dehydration with salt solution (ODSa), microwave heating (MV), and hot air-drying (HD). The moisture content, oil content, L*, b*, and index of firmness of all pre-treated banana chips were significantly decreased, whereas values for a*, volume shrinkage, and hardness were increased when compared to those without pre-treatment. The ODSu sample provided the lowest oil content. The highest volume shrinkage was obtained from HD and MV treatments. Sensory evaluation revealed that VF chips exhibited the highest scores in color, crispiness, and oiliness when compared to AF chips. ODSu and ODSa samples positively affected the color, crispiness, and taste properties. Practical applications Although there have been several techniques aimed at reducing the oil content of chips, the particular method investigated in the current work, pre-treatment before VF, has not so far been investigated. The application of pre-treatment processes prior vacuum or atmospheric frying in this study could reduce oil absorption and increase the score in sensory properties of fried banana chips. This process could be applied in other fried products in commercial scale.

Effect of Pretreatment Process on Properties of Aerospace Al-Li Alloy Sulfuric Acid Anodic Film

Effect of Pretreatment Process on Properties of Aerospace Al-Li Alloy Sulfuric Acid Anodic Film

Effect of Combining Electron Beam Irradiation and Alkaline Pretreatments of OPEFB for Enzymatic Hydrolysis and Fermentation of Ethanol

The effect of pretreatment process from the combination of electron beam irradiation and alkaline to Oil Palm Empty Fruit Bunch (OPEFB) was studied. The combination of pretreatment method was considered as an alternative way to increase glucose yield. In this study, OPEFB was pretreated using Electron Beam Irradiation (EBI) at 100 kGy and 300 kGy and followed by chemical pretreatment. In chemical pretreatment, irradiated OPEFB was reacted with sodium hydroxide 6% and 10% in stirred vessel at 4 bars and 150 oC for 30 min. The effectiveness of pretreatment was evaluated by calculating the composition of chemical component using National Renewable Energy Laboratory (NREL) Method. The samples which were hydrolyzed using enzymes with the addition of 30 FPU of CellicCTec2 per gram of pretreated biomass resulted high glucose in the amount of 9.86%. The fermentation process using Saccharomyces cereviceae obtained the highest ethanol concentration for 5.36% at 72h. The combination of the two pretreatment methods gave an effect on the weight loss, chemical composition, structure, and enzymatic hydrolysis product

Effect of pretreatment process on the characteristics of activated carbons produced from chemical activation of scrap tire

The effect of pretreatment process has been studied on the properties of prepared activated carbons (AC) from scrap tires. The activation of ACs was chemically performed by KOH as activating agent. Different pretreatment agents have been used including toluene and three strong acids (nitric, hydrochloric, and sulfuric). The obtained results indicate that the pretreatment process can significantly improve the adsorption capacity (iodine number) of the prepared ACs. The toluene‐H2SO4 pretreatment process yielded the best results improving the iodine number of the ACs up to ∼20%. The carbon yield of around 25% with density of 0.31 g/cm3 was achieved for the ACs pretreated with toluene‐H2SO4 and chemically activated with KOH. The surface characteristics of ACs were studied by scanning electron microscopy revealing structural transformation of the ACs into well‐developed porous media caused by toluene‐H2SO4 pretreatment. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 796–801, 2017

Survey on the effects of pre-treatment process with acid on the capacity of gelatin extraction from pork skin

Gelatin is increasingly becoming an important raw material in many different fields. The pretreatment stage of the production of gelatin from pork skin plays an important role, it has big effect on the quality of obtained products. A survey on 5 types of acid HCl, H2SO4, H3PO4, CH3COOH, Citric was conducted. It showed that the influence of these types of acid on the pretreatment process was different. Acetic acid made the best result with the protein after extraction reaching 54.88 mg/ml, the product bloom reached 223. The most appropriate proportion of acetic acid was 3%. A survey on the effect of soaking time on the capacity of extraction was conducted. The result showed that the 16-hour extraction brought the best result reaching 56.16 mg/ml, the product bloom reached 245. The most suitable proportion of soaking pork skin:acid was 1:2. The most appropriate temperature of acid immersion was 15°C, at which the protein after extraction reached 68.39 mg/ml, the product bloom reached 299, the viscosity reached 23 mPas.
 Gelatin ngày càng trở thành nguồn nguyên liệu quan trọng trong nhiều lĩnh vực khác nhau. Giai đoạn tiền xử lý của việc sản xuất gelatin từ bì lợn đóng vai trò quan trọng và có ảnh hưởng lớn tới chất lượng sản phẩm thu được. Khảo sát 5 loại axit: HCl, H2SO4, H3PO4, CH3COOH, Citric, thấy rằng ảnh hưởng của các loại axit này trong quá trình tiền xử lý là khác nhau. Axit axetic cho kết quả tốt nhất với hàm lượng protein sau trích ly đạt 54,88 mg/ml, độ bloom sản phẩm đạt 223. Nồng độ thích hợp nhất của axit axetic là 3%. Khảo sát ảnh hưởng của thời gian ngâm đến khả năng trích ly thấy rằng 16 giờ cho kết quả tốt nhất đạt 56,16 mg/ml, độ bloom sản phẩm đạt 245. Tỷ lệ ngâm bì lợn: axit thích hợp nhất là 1:2. Nhiệt độ ngâm axit thích hợp nhất là 15oC, tại đó hàm lượng protein sau trích ly đạt 68,39 mg/ml, độ bloom sản phẩm đạt 299, độ nhớt đạt 23 mPs.

The Influence of Non-selective Oxidation on Differently Pre-treated Cotton Yarns Properties

Differntly pre-treated cotton yarns were subjected to non-selective oxidation with perchloric acid and the effects of pre-treatment processes on oxidation were studied through functional groups quantity, and degradation through mechanical properties and degree of polymerization. Different pre-treatments include, different scouring (with alkali, alkaline and acid pectinase), mercerization-different scouring as well as different scouring-mercerization. The quantity of functional groups was studied by measuring carboxyl groups with methylene blue and calcium-acetate methods and aldehyde groups with iodine and tetrazolium (TTC) methods. Pre-treatment processes affect the degree of elimination of non-cellulosic components of cotton and have strong influence on oxidation process. The non-selective oxidation of enzymatic scoured cotton with perchloric acid has introduced carboxyl and aldehyde groups without serious degradation of cotton yarns, confirmed by only 15 % decreasing of tensile strength and 8 % decreasing of degree of polymerization. DOI: http://dx.doi.org/10.5755/j01.ms.22.3.12110

PRETREATMENT AND OPTIMIZATION STUDIES ON THE EXTRACTION OF ANTIOXIDANT COMPONENTS FROM PHALERIA MACROCARPA FRUIT

Phaleria macrocarpa, one of many indigenous Indonesian plants, possesses potent antioxidant activity and hence may serve as natural food preservative, cosmetic ingredients, as well as food supplement. This study is the second stage of a three-year project to isolate antioxidant components in Phaleria macrocarpa for natural preservative application. The objective of this study is to investigate the effect of pretreatment process on the oleoresin and bioactive content, and to optimize three parameters in the extraction process, i.e. ethanol concentration, F/S ratio, and temperature. The selected pretreatment method was solid-liquid extraction using a non-polar solvent (n-hexane) and a semi polar solvent (ethyl acetate). The pretreatment process produced less sticky oleoresin, especially with n-hexane, due to significant removal of tannin, and had only a little effect (less than 4%) on the antioxidant activity and flavonoid content. However, the pretreatment indeed reduced the yield of oleoresin by around 10%. Three important parameters of the extraction process were optimized using Central Composite Experimental Design by varying operation temperature from 27.5 °C to 64.5 °C, F/S ratio from 1 : 11.5 g/mL to 1 : 53.5 g/mL, and ethanol concentration from 14 %-v/v to 93 %-v/v. The response surface analysis showed a maximum point at ethanol concentration of 30 %-v/v, F/S ratio of 1 : 45 g/mL, and temperature at 57 oC which gave the oleoresin yield of 1.00 g oleoresin/g dry feed and antioxidant activities of 2.99 μmol DPPH/mg oleoresin.

Optimization of Liquid Ammonia Treatment for Enzymatic Hydrolysis of Miscanthus sinensis Anderss

Miscanthus biomass yield high, high photosynthetic efficiency, fast growth, easy breeding, widely distributed, is suitable as raw materials for the production of fuel ethanol. In this paper, the method of the pretreatment of liquid ammonia for Miscanthus, using the pretreatment of liquid ammonia to overcome biomass recalcitrance, adding cellulase enzyme, and the monosaccharide content is determined by using high performance liquid chromatography (HPLC). Effect of pretreatment process on the enzyme solution effect of awn, conducts the research to the water processing rate, temperature, residence time, amount of ammonia, the amount of H2O2 parameters. Data shows that, in the moisture content of 80%, temperature 130?C, loading amount of ammonia 2:1, residence time 10 min, the glucan and xylan enzyme conversion rate are 73.23% and 73.28% respectively. After a mass balance, dry base mans per 100 g can get glucose 28.96 g and xylan 17.25 g.

Industrial-scale bioethanol production from brown algae: Effects of pretreatment processes on plant economics

Brown algae, considered as the third generation biomass, offer several advantages over lignocellulosic biomass. However, the current high cost of seaweed cultivation hampers the industrialization of macroalgae-based biofuel production. The aim of this study is to determine the maximum dry seaweed price (MDSP) as an upper limit for purchasing price of brown algae at bioethanol plant gates. In addition, a minimum ethanol-selling price (MESP) was calculated by considering the state-of-the-art bioethanol production technology and current brown algae-cultivation costs. A new simple pretreatment process was economically validated and compared with the traditional acid thermal hydrolysis known as combined pretreatment. The processes were simulated at the scales of 80,000 and 400,000ton/year of dry brown algae using the Aspen Plus v.8.4 software, and techno-economic models were developed based on mass and energy balance. MDSP for the simple and combined processes was calculated as 64.6 and 26$/ton (80,000ton/year) and 91.3 and 71.5$/ton (400,000ton/year), respectively. In addition, MESP for the simple and combined processes was determined as 2.39 and 2.85$/gal (80,000ton/year) and 2.08 and 2.33$/gal (400,000ton/year), respectively. These results indicate that the simple pretreatment is economically superior to the combined pretreatment. A comprehensive sensitivity analysis showed that seaweed price had the highest impact on MESP, thereby confirming that the cost-effective large-scale seaweed cultivation is the key to the success of macroalgae-based biofuel production.