Effect Of Pretreatment Methods Research Articles

Effect of Pretreatment Methods on Seed Germination of Honey Plant, Phellodendron amurense

Effect of Pretreatment Methods on Seed Germination of Honey Plant, Phellodendron amurense

Effect of pretreatment methods on the synergism of cellulase and xylanase during the hydrolysis of bagasse

The effect of pretreatment with peracetic acid (PAA) or an ionic liquid (1-ethyl-3-methylimidazolium acetate, [Emim][OAc]) on the synergism between endoglucanase and endoxylanase in the hydrolysis of bagasse was investigated. An endoglucanase, Cel6A, with a carbohydrate-binding module (CBM) and two endoxylanases, XynZ-C without a CBM and Xyn11A with an intrinsic xylan/cellulose binding module (XBM), were selected. The hemicellulose content, especially arabinan, and the cellulose crystallinity of bagasse were found to affect the cellulase–xylanase synergism. More specifically, higher synergism (above 3.4) was observed for glucan conversion, at low levels of arabinan (0.9%), during the hydrolysis of PAA pretreated bagasse. In contrast, [Emim][OAc] pretreated bagasse, showed lower cellulose crystallinity and achieved higher synergism (over 1.9) for xylan conversion. Ultimately, the combination of Cel6A and Xyn11A resulted in higher synergism for glucan conversion than the combination of Cel6A with XynZ-C, indicating the importance of the molecular architecture of enzymes for metabolic synergism.

Effect of Pre-treatment Methods and Germination Promoter on the Seed Emergence of Zanthoxylum schinifolium

Effect of Pre-treatment Methods and Germination Promoter on the Seed Emergence of Zanthoxylum schinifolium

Effects of Pretreatment Methods on Electrodes and SOFC Performance

Commercially available tapes (anode, electrolyte) and paste (cathode) were choosen to prepare anode-supported cells for solid oxide fuel cell applications. For both anode-supported cells or electrolyte-supported cells, the anode needs pretreatment to reduce NiO/YSZ to Ni/YSZ to increase its conductivity as well as its catalytic characteristics. In this study, the effects of different pretreatments (open-circuit, closed-circuit) on cathode and anodes as well as SOFC performance are investigated. To investigate the influence of closed-circuit pretreatment on the NiO/YSZ anode alone, a Pt cathode is utilized as reference for comparison with the LSM cathode. The characterization of the electrical resistance, AC impedance, and SOFC performance of the resulting electrodes and/or anode-supported cell were carried out. It’s found that the influence of open-circuit pretreatment on the LSM cathode is limited. However, the influence of closed-circuit pretreatment on both the LSM cathode and NiO/YSZ anode and the resulting SOFC performance is profound. The effect of closed-circuit pretreatment on the NiO/YSZ anode is attributed to its change of electronic/pore structure as well as catalytic characteristics. With closed-circuit pretreatment, the SOFC performance improved greatly from the change of LSM cathode (and Pt reference) compared to the Ni/YSZ anode.

Effect of pretreatment on membrane fouling and VMD performance in the treatment of RO-concentrated wastewater

The polyvinylidene fluoride hollow fiber hydrophobic membrane was applied in vacuum membrane distillation (VMD) process for the treatment of reverse osmosis-concentrated wastewater from a steel plant. The effects of pretreatment methods on the CODcr removal, the performance and membrane fouling of VMD process were studied. The morphology and composition of the fouling layer were studied by scanning electron microscope and energy dispersive spectroscopy, respectively. The reason for the flux declination in VMD process was discussed. The results showed that the CODcr removal reached 40%, and the flux of VMD process was increased after the pretreatment of coagulation and ultrafiltration, when the concentration factor reached eight, the flux of VMD process using properly pretreated solution was 30% higher than that using un-pretreated solution as the feed. The membrane surface morphology and elemental analysis testified that the fouling of membrane surface was obviously alleviated by pretreatment.

Biohydrogen production from ricebran using Clostridium saccharoperbutylacetonicum N1-4

Treated ricebran hydrolysate was fermented anaerobically using Clostridium saccharoperbutylacetonicum N1-4 at an initial pH of 6 ± 0.2 and an operating temperature of 30 °C for production of hydrogen. The effects of different pretreatment methods on the liberation of sugar from 100 g of ricebran per litre of medium (distilled water) were investigated. In addition, the effects of the pretreatment method on ricebran hydrolysates of different initial ricebran concentrations on liberated sugar as well as the effects of the initial inoculum concentration, ricebran (substrate) concentration, and FeSO4·7H2O concentration on the yield as well as the productivity of hydrogen were investigated. The combination of enzymatic hydrolysis and a boiling pretreatment method produced the most fermentable sugar, 29.03 ± 0.0 g/L from 100 g of ricebran per litre of medium (distilled water), while the amount of sugar liberated by ricebran hydrolysates of different initial ricebran concentrations upon pretreatment monotonically increased with the initial ricebran concentration. The increment in substrate, inoculum, and FeSO4·7H2O concentrations had a significantly positive effect (p < 0.05) on both the yield and productivity of hydrogen. The maximum hydrogen gas yield (YP/S) and productivity of 3.37 mol-H2 per mol-sugar consumed and 7.58 mmol/(L h), respectively, were obtained from ricebran hydrolysate with a 100 g/L ricebran concentration (equivalent to 28.59 ± 1.27 g sugar/L). In other experiments, 0.03 g/L FeSO4·7H2O and 1.5 g/L inoculum resulted in the best hydrogen gas yield and productivity from ricebran hydrolysates.

Improvement of the energy conversion efficiency of Chlorella pyrenoidosa biomass by a three-stage process comprising dark fermentation, photofermentation, and methanogenesis

The effects of pre-treatment methods on saccharification and hydrogen fermentation of Chlorella pyrenoidosa biomass were investigated. When raw biomass and biomass pre-treated by steam heating, by microwave heating, and by ultrasonication were used as feedstock, the hydrogen yields were only 8.8-12.7 ml/g total volatile solids (TVS) during dark fermentation. When biomass was pre-treated by steam heating with diluted acid and by microwave heating with diluted acid, the dark hydrogen yields significantly increased to 75.6 ml/g TVS and 83.3 ml/g TVS, respectively. Steam heating with diluted acid is the preferred pre-treatment method of C. pyrenoidosa biomass to improve hydrogen yield during dark fermentation and photofermentation, which is followed by methanogenesis to increase energy conversion efficiency (ECE). A total hydrogen yield of 198.3 ml/g TVS and a methane yield of 186.2 ml/g TVS corresponding to an overall ECE of 34.0% were obtained through the three-stage process (dark fermentation, photofermentation, and methanogenesis).

The effect of pre-treatment methods on the yield and taste of cashew kernels (Anacardium occidentale L.)

Pre-treatment methods that cashew nuts (Anacardium occidentale L.) are subjected to before shelling are crucial in influencing the yield of whole kernels and the aftertaste. In this work, raw cashew nuts were subjected to different times of steaming, boiling, and roasting as pre-treatment methods and their effect on yield and panellists’ preference for taste followed by spectrophotometric determination of residual cashew nut shell liquid (CNSL) on kernels were assessed. After initial comparison of kernels obtained from similarly pre-treated samples, the samples boiled for 15 min, steamed for 30 min, and conditioned before roasting were selected. Further analysis showed no significant differences in the yield of all grades of cashew kernels from cashew nuts steamed for 30 min (71%) and that boiled for 15 min (69%). The sample conditioned before roasting, had a significantly lower whole kernel recovery (51%) but significantly higher percentage yield for halves (37%) than the steamed (19%) and boiled samples (21%).Panellists preferred the sample boiled for 15 min as having the least after-taste, followed by the sample steamed for 30 min, with the sample conditioned before roasting being least preferred. Spectrophotometric results of residual CNSL on kernels were 25, 54, and 71 ppm, respectively for samples boiled for 15 min, steamed for 30 min, and the one conditioned before roasting, buttressing the sensory evaluation results. Key words: Cashew nuts, steaming, boiling, roasting, spectrophotometric determination.

Kinetic modeling of enzymatic hydrolysis of pretreated kitchen wastes for enhancing bioethanol production

It is well known that use of low cost and abundant waste materials in microbial fermentations can reduce product costs. Kitchen wastes disposed of in large amounts from cafeterias, restaurants, dining halls, food processing plants, and household kitchens contain high amounts of carbohydrate components such as glucose, starch, and cellulose. Efficient utilization of these sugars is another opportunity to reduce ethanol costs. In this study, the effect of pretreatment methods (hot water, acid solutions, and a control) on enzymatic hydrolysis of kitchen wastes was evaluated using a kinetic modeling approach. Fermentation experiments conducted with and without traditional fermentation nutrients were assessed at constant conditions of pH 4.5 and temperature of 30°C for 48h using commercial dry baker’s yeast, Saccharomyces cerevisiae. The control, which involved no treatment, and hot water treated samples gave close glucose concentrations after 6h. The highest and lowest rates of glucose production were found as 0.644 and 0.128 (h−1) for the control (or no-pretreated (NPT)) and 1% acid solutions, respectively. The fermentation results indicated that final ethanol concentrations are not significantly improved by adding nutrients (17.2–23.3g/L). Thus, it was concluded that product cost can be lowered to a large extent if (1) kitchen wastes are used as a substrate, (2) no fermentation nutrient is used, and (3) hydrolysis time is applied for about 6h. Further optimization study is needed to increase the yield to higher levels.

Research on the Interface Bonding Conditions of Bimetallic Rolls Manufactured by Liquid-Solid Bonding Method

Bimetallic rolls’ interfaces manufactured by liquid-solid bonding method have been studied in the manuscript. Effect of pretreatment method of roll core, pouring temperature and preheating temperature of core to the bonding of interfaces are analyzed. Line scanning to the element chromium is done with SEM, the effect of technology to the organize structure and element diffusion is researched; Shear stress experiment of interface is done to analyze the effect of technology to bond strength.

Effects of pretreatment methods on cassava wastewater for biohydrogen production optimization

Batch production of biohydrogen from cassava wastewater pretreated with (i) sonication, (ii) OPTIMASH BG ® (enzyme), and (iii) α-amylase (enzyme) were investigated using anaerobic seed sludge subjected to heat pretreatment at 105 °C for 90 min. Hydrogen yield at pH 7.0 for cassava wastewater pretreated with sonication for 45 min using anaerobic seed sludge was 0.913 mol H 2/g COD. Results from pretreatment with OPTIMASH BG ® at 0.20% and pH 7 showed a hydrogen yield of 4.24 mol H 2/g COD. Superior results were obtained when the wastewater was pretreated with α-amylase at 0.20% at pH 7 with a hydrogen yield of 5.02 mol H 2/g COD. In all cases, no methane production was observed when using heat-treated sludge as seed inoculum. Percentage COD removal was found to be highest (60%) using α-amylase as pretreatment followed by OPTIMASH BG ® at 54% and sonication (40% reduction rate). Results further suggested that cassava wastewater is one of the potential sources of renewable biomass to produce hydrogen.

Co-hydrolysis of hydrothermal and dilute acid pretreated populus slurries to support development of a high-throughput pretreatment system

BackgroundThe BioEnergy Science Center (BESC) developed a high-throughput screening method to rapidly identify low-recalcitrance biomass variants. Because the customary separation and analysis of liquid and solids between pretreatment and enzymatic hydrolysis used in conventional analyses is slow, labor-intensive and very difficult to automate, a streamlined approach we term 'co-hydrolysis' was developed. In this method, the solids and liquid in the pretreated biomass slurry are not separated, but instead hydrolysis is performed by adding enzymes to the whole pretreated slurry. The effects of pretreatment method, severity and solids loading on co-hydrolysis performance were investigated.ResultsFor hydrothermal pretreatment at solids concentrations of 0.5 to 2%, high enzyme protein loadings of about 100 mg/g of substrate (glucan plus xylan) in the original poplar wood achieved glucose and xylose yields for co-hydrolysis that were comparable with those for washed solids. In addition, although poplar wood sugar yields from co-hydrolysis at 2% solids concentrations fell short of those from hydrolysis of washed solids after dilute sulfuric acid pretreatment even at high enzyme loadings, pretreatment at 0.5% solids concentrations resulted in similar yields for all but the lowest enzyme loading.ConclusionsOverall, the influence of severity on susceptibility of pretreated substrates to enzymatic hydrolysis was clearly discernable, showing co-hydrolysis to be a viable approach for identifying plant-pretreatment-enzyme combinations with substantial advantages for sugar production.

Using pretreated waste oyster and clam shells and microwave hydrothermal treatment to recover boron from concentrated wastewater

Boron is an essential nutrient for animals and plants, but it can be harmful in excessive levels. In this study, three types of crushed shells (oyster, hard clam and freshwater clam) were pretreated and then reused as mineralizers to remove and recover the boron from concentrated wastewater by using the microwave hydrothermal method. Chemical and physical properties of raw and pretreated crushed shells were determined and compared using SEM, XRD, BET and WD-XRF. Effects of pretreatment method (heated or pyrolysis), particle sizes, initial boron concentrations, reaction times and shells dosages on boron recovery were investigated. The oyster shells pretreated by heat performed better than heated hard clam and freshwater clam shells, and the boron recovery efficiency reached around 95% within 10min of reaction time. The experimental results indicate that the pretreated oyster shell is an effective mineralizer for removal and recovery of boron from concentrated wastewater.

Cellulolytic Enzymes Production via Solid-State Fermentation: Effect of Pretreatment Methods on Physicochemical Characteristics of Substrate.

We investigated the effect of pretreatment on the physicochemical characteristics—crystallinity, bed porosity, and volumetric specific surface of soybean hulls and production of cellulolytic enzymes in solid-state fermentation of Trichoderma reesei and Aspergillus oryzae cultures. Mild acid and alkali and steam pretreatments significantly increased crystallinity and bed porosity without significant change inholocellulosic composition of substrate. Crystalline and porous steam-pretreated soybean hulls inoculated with T. reesei culture had 4 filter paper units (FPU)/g-ds, 0.6 IU/g-ds β-glucosidase, and 45 IU/g-ds endocellulase, whereas untreated hulls had 0.75 FPU/g-ds, 0.06 IU/g-ds β-glucosidase, and 7.29 IU/g-ds endocellulase enzyme activities. In A. oryzae steam-pretreated soybean hulls had 47.10 IU/g-ds endocellulase compared to 30.82 IU/g-ds in untreated soybean hulls. Generalized linear statistical model fitted to enzyme activity data showed that effects of physicochemical characteristics on enzymes production were both culture and enzyme specific. The paper shows a correlation between substrate physicochemical properties and enzyme production.

Effect of Pre-Treatment Palm Oil Mill Effluent POME on Biohydrogen Production by Local Isolate &lt;i&gt;Clostridium Butyricum&lt;/i&gt;

Palm oil mill effluent (POME) contains approximately 6% fiber. The effectiveness of pre-treatment on POME can serve a very good feedstock for hydrogen production in fermentation process. In this research, the effectiveness of pre-treatment methods on POME treated using acid and base were analysed based total carbohydrate and reducing sugar content. By using 1M NaOH with heat treatment, 26.12% carbon source converted to reducing sugar while by using 1M H2SO4 with heat treatment, over 32.09% carbon source converted to reducing sugar. The highest increment of total carbohydrate where from acid-heat treatment with 26.1% increment from initial concentration. At the initial pH (5.5) with fermentation temperature 37°C, the highest hydrogen production rate given by acid-heat treatment was 0.5mL H2/mL POME. Different for initial pH 7.0 with the same temperature, the highest hydrogen produced rate was given by base-heat treatment with 0.59 mL H2/mL POME. The production of hydrogen in 2L bioreactor given much higher hydrogen production compare to production in serum bottle. This fermentation was run in batch mode with initial pH 7 and control at 5.5. The maximum hydrogen produce was 4304 mL H2/ L POME from acid-heat treatment.

Effects of Pretreatment Methods and Bands Selection on Soil Nutrient Hyperspectral Evaluation

Abstract By using the laboratory reflectance spectra of 42 soil samples, the effects of spectral preprocessing and spectral band selection on predictive models of total kalian (TK) of soil were studied,. The results show that the first order derivative has the maximal correlation coefficient between all pretreatments, including Savizky-Golay smothing(S-G smothing), multiplication scatter correction(MSC), the first order derivative and the second order derivative. Compared with other bands selected and the pretreatment methods, the first order derivative which was used at 554-600 nm and 2205-2213 with multple linear regression(MLR) method combined with PC transformation could obtain a better TK prediction model, whose maximum determination coefficient(R2) is 0.774 and minimum root mean square error(RMSE) is 1.109.

Effects of pretreatment methods on solubilization of beet-pulp and bio-hydrogen production yield

Sugar processing wastewater and beet-pulp are two major waste streams of sugar-beet processing plants. Contrary to wastewater, beet-pulp is generally used as animal feed in cattle-raising industry. However, it can serve as a substrate for bio-hydrogen production which corresponds to a higher valorization of beet-pulp. Moreover, pretreatment of lignocellulosic materials like beet-pulp is needed in order to improve overall energy efficiency and enable economic feasibility of bio-hydrogen production. Therefore, the effect pretreatment methods (alkaline, thermal, microwave, thermal-alkaline and microwave-alkaline) on bio-hydrogen production from sugar beet-pulp through dark fermentation were investigated in this study. Reactors pretreated with alkaline, microwave-alkaline and thermal-alkaline methods yielded significant solubilization of beet-pulp compared to others. Therefore, in the second phase of the study, they were used to pretreat the beet-pulp which was then subjected to dark fermentation for bio-hydrogen production. Maximum bio-hydrogen production yield of 115.6 mL H 2/g COD was observed in reactor which contained alkaline pretreated beet-pulp.

Effects of smoking on trace metal levels in saliva

To compare the salivary levels of trace metals between non-smokers and smokers using inductively coupled plasma mass spectroscopy (ICP-MS). The effect of pretreatment methods on the accuracy of ICP-MS analysis and daily variations in trace metal levels in saliva were also investigated. The participants were 10 male non-smokers (mean age: 27.4 ± 3.4 years) and 30 male smokers (mean age: 26.5 ± 4.1 years). Unstimulated whole saliva was collected. Salivary flow rate, the number of metal restorations in the oral cavity, the level of blood contamination in the saliva and the levels of cotinine and trace metals in the saliva of each participant were determined. Direct dilution of saliva samples with nitric acid showed the most accurate ICP-MS results. Trace metal levels in saliva showed wide daily variations. They were not affected by the number of metal restorations. Trace metal concentrations of saliva samples without blood contamination were much lower than the previously reported values. Salivary levels of cotinine and aluminum were significantly increased in smokers. Saliva can be a medium for trace metal analysis. Salivary levels of cotinine and aluminum can be useful markers to evaluate smoking status.

Effect of Pretreatment Methods on L-Lactic Acid Production from Vinasse Fermentation

To achieve high value-added utilization, vinasse was chosen as raw material for l-lactic acid production. Alkali methods, microwave were used to treat vinasse and the optimum parameters during the process were investigated. The results showed that the best pretreatment way was the combination of alkali concentration of 8% and microwave power 700W, corresponding maximum lactic acid concentration was 17.5g/L, higher than those of the independent method utilized, the fermentation time could be one day earlier than other methods. The conversion rate of preprocessed vinasse to L-lactic acid and utilization rate of cellulose and hemi-cellulose could reach 23.8% and 71%, respectively. The optimized pretreatment could effectively realize hydrolysis of vinasse and make it an ideal sources for further utilization.

The effect of pre-treatment methods on morphology and size distribution of multi-walledcarbon nanotubes

Multi-walled carbon nanotubes (MWCNTs) are important materials with aunique combination of mechanical, electrical and thermal properties. MWCNTsusually exist as tangled aggregates embedding impurities such as catalysts oramorphous carbon. Therefore, purification and cutting process are essentialprocesses to get the well-dispersed solutions in solvents or a polymer matrix fordiverse practical applications. In this study, we used MWCNTs with high purity(>95%) and focused on the cutting effects on the size distribution of MWCNTs. Their sizedistribution after the cutting process is expected to be a very important factor indetermining the final properties of the polymer–MWCNT composite. Gel permeationchromatography (GPC) was effectively demonstrated in analyzing the effect oftreatment methods on a size distribution of pre-treated MWCNTs in organic solvent.MWCNT was treated by two different methods. One is an oxidation process withH2SO4/HNO3 solution and the other is an ultrasonic process with high power. MWCNTs were shortenedsimply by applying high power ultrasonication with narrow length distribution. Meanwhile,the acid-treated MWCNTs became much broader in their sizes and more flexible in theirrigidities. These differences led to a different behavior in electric conductivity. Thesestudies promise to optimize pre-treatment processes for tailoring suitable MWCNTstowards future applications.