• Title/Summary/Keyword: Alkaline Pretreatment

Search Result 116, Processing Time 0.03 seconds

Comparison of pretreatment of fallen leaves for application evaluation by Bio-ethanol raw material (바이오에탄올 원료로서 활용평가를 위한 낙엽의 전처리 비교)

  • Choi, Hyoyeon;Kim, Jaehyung;Pak, Daewon
    • Journal of Energy Engineering
    • /
    • v.23 no.3
    • /
    • pp.241-246
    • /
    • 2014
  • This study is to compare characteristics of saccharification reactions applying to enzymatic hydrolysis of pretreated fallen leaves for bio-ethanol production. It experimented pretreatment of acid, alkaline in the chemical. This experiment includes preteatment of acid and alkaline in chemical, soaking, shaking and autoclaving method, which were applied to biomass. In result, the glucose production from alkaline-NaOH method was 263 mg glucose/ g biomass comparing with them of acid-HCl method. Thus, alkaline-NaOH method is superior than the acid-HCl method for chemical preteatment of fallen leaves. Also, when various chemical treatments were compared, they were all. Based on the results of this study, we found that leaves, one of biomass, are possible in pretreatment and enzymatic hydrolysis process, and they are likely to affect bio-ethanol production in the future.

Optimization of soaking in aqueous ammonia pretreatment of canola residues for sugar production (당 생산을 위한 카놀라 부산물의 암모니아 침지 전처리 공정의 최적화)

  • Yoo, Hah-Young;Kim, Sung Bong;Lee, Sang Jun;Lee, Ja Hyun;Suh, Young Joon;Kim, Seung Wook
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2011.11a
    • /
    • pp.114.1-114.1
    • /
    • 2011
  • Bioenergy production from lignocellulosic biomass and agriculture wastes have been attracted because of its sustainable and non-edible source. Especially, canola is considered as one of the best feedstock for renewable fuel production. Oil extracted canola and its agriculture residues are reuseable for bioethanol production. However, a pretreatment step is required before enzymatic hydrolysis to disrupt recalcitrant lignocellulosic matrix. To increase the sugar conversion, more efficient pretreatment process was necessary for removal of saccharification barriers such as lignin. Alkaline pretreatment makes the lignocellulose swollen through solvation and induces more porous structure for enzyme access. In our previous work, aqueous ammonia (1~20%) was utilized for alkaline reagent to increase the crystallinity of canola residues pretreatment. In this study, significant factors for efficient soaking in aqueous ammonia pretreatment on canola residues was optimized by using the response surface method (RSM). Based on the fundamental experiments, the real values of factors at the center (0) were determined as follows; $70^{\circ}C$ of temperature, 17.5% of ammonia concentration and 18 h of reaction time in the experiment design using central composition design (CCD). A statistical model predicted that the highest removal yield of lignin was 54% at the following optimized reaction conditions: $72.68^{\circ}C$ of temperature, 18.30% of ammonia concentration and 18.30 h of reaction time. Finally, maximum theoretical yields of soaking in aqueous ammonia pretreatment were 42.23% of glucose and 22.68% of xylose.

  • PDF

Cleaning Effects by NH4OH Solution on Surface of Cu Film for Semiconductor Devices (NH4OH용액이 반도체 소자용 구리 박막 표면에 미치는 영향)

  • Lee, Youn-Seoung;Noh, Sang-Soo;Rha, Sa-Kyun
    • Korean Journal of Materials Research
    • /
    • v.22 no.9
    • /
    • pp.459-464
    • /
    • 2012
  • We investigated cleaning effects using $NH_4OH$ solution on the surface of Cu film. A 20 nm Cu film was deposited on Ti / p-Si (100) by sputter deposition and was exposed to air for growth of the native Cu oxide. In order to remove the Cu native oxide, an $NH_4OH$ cleaning process with and without TS-40A pre-treatment was carried out. After the $NH_4OH$ cleaning without TS-40A pretreatment, the sheet resistance Rs of the Cu film and the surface morphology changed slightly(${\Delta}Rs:{\sim}10m{\Omega}/sq.$). On the other hand, after $NH_4OH$ cleaning with TS-40A pretreatment, the Rs of the Cu film changed abruptly (${\Delta}Rs:till{\sim}700m{\Omega}/sq.$); in addition, cracks showed on the surface of the Cu film. According to XPS results, Si ingredient was detected on the surface of all Cu films pretreated with TS-40A. This Si ingredient(a kind of silicate) may result from the TS-40A solution, because sodium metasilicate is included in TS-40A as an alkaline degreasing agent. Finally, we found that the $NH_4OH$ cleaning process without pretreatment using an alkaline cleanser containing a silicate ingredient is more useful at removing Cu oxides on Cu film. In addition, we found that in the $NH_4OH$ cleaning process, an alkaline cleanser like Metex TS-40A, containing sodium metasilicate, can cause cracks on the surface of Cu film.

Optimization of Bio-based Succinic Acid Production from Hardwood Using the Two Stage pretreatments

  • Jung, Ji Young;Jo, Jong Soo;Kim, Young Wun;Yoon, Byeng Tae;Kim, Choon Gil;Yang, Jae Kyung
    • Journal of the Korean Wood Science and Technology
    • /
    • v.41 no.2
    • /
    • pp.111-122
    • /
    • 2013
  • The steam explosion-chemical pretreatment is a more effective wood pretreatment technique than the conventional physical pretreatment by accelerating reactions during the pretreatment process. In this paper, two-stage pretreatment processes of hardwood were investigated for its enzymatic hydrolysis and the succinic acid yield from the pretreated solid. The first stage pretreatment was performed under conditions of low severity to optimize the amount of solid recovery. In the second stage pretreatment washed solid material from the first stage pretreatment step was impregnated again with chemical (alkaline or chlorine-based chemicals) to remove a portion of the lignin, and to make the cellulose more accessible to enzymatic attack. The effects of pretreatment were assessed by enzymatic hydrolysis and fermentation, after the two stage pretreatments. Maximum succinic acid yield (16.1 g $L^{-1}$ and 77.5%) was obtained when the two stage pretreatments were performed at steam explosion -3% KOH.

The Characteristics of Alkaline Pretreatment Methods of Cellulosic Biomass (섬유소계 바이오매스의 분별을 위한 다양한 알칼리 전처리 특성)

  • Kim, Jun Seok
    • Korean Chemical Engineering Research
    • /
    • v.51 no.3
    • /
    • pp.303-307
    • /
    • 2013
  • This study compares the efficacy of soaking and percolation pretreatments with alkaline solutions for lignocellulosic biomass. Various biomass such as rice straw and barley were pretreated by soaking processes in various alkaline solutions including sodium hydroxide, potassium hydroxide, aqueous ammonia and sodium carbonate. The enzymatic digestibility of rice straw and barley that had been pretreated by soaking in aqueous ammonia was over 80%. Eucalyptus residue, Larix leptolepis and Pinus rigida exhibited relatively low enzymatic digestibility. Nevertheless, the enzymatic digestibility of pretreated eucalyptus residue was increased by five times compared to that of the initial biomass. And, the enzymatic digestibility of the percolation pretreated eucalyptus residue was increased 12 times.

Radiomodifying Potential of Panax ginseng in Liver of Swiss Albino Mice against Gamma Radiation

  • Sharma, Mukesh Kumar;Kumar, Madhu;Kumar, Ashok
    • Journal of Ginseng Research
    • /
    • v.28 no.2
    • /
    • pp.78-86
    • /
    • 2004
  • Panax ginseng occupies an important role in the folk medicine of China, Korea and Japan. The present study was undertaken to determine the radioprotective efficacy of ginseng root extract in the liver of Swiss albino mice. The animals were divided into 4 groups. Group I-Only vehicle was administered. Group II-The animals received 10 mg/kg body weight ginseng root extract i.p. for 4 consecutive days. Group III-Animals were irradiated with 8Gy gamma radiation at the dose rate of 1.69 Gy/min at the distance of 80 ems. Group IV-Animals were given by ginseng root extract (10 mg/kg body weight) continuously for 4 days and on 4th day they were irradiated with 8 Gy gamma radiation after 30 min. The animals from above groups were autopsied on 1,3,7,14 and 30 days. Biochemical estimations of phosphatases (acid & alkaline), LDH (lactate dehydrogenase), LPO (lipid peroxidation) and GSH (reduced glutathione) in liver and SGOT (serum glutamate oxaloacetate transaminase), SGPT (serum glutamate pyruvate transaminase) and alkaline phosphatase in serum were done. In ginseng treated group acid phosphatase (ACP), alkaline phosphatase (ALP), LPO and LDH in liver and SGOT, SGPT and alkaline phosphatase in serum did not show any significant alteration. However, a significant increase in GSH content in liver was recorded. In irradiated group there was a significant increase in ACP, ALP and LPO content in liver and SGOT & SGPT in serum was noted. Whereas, a significant decrease was recorded in GSH and LDH activity in liver and alkaline phosphatase activity in serum. Pretreatment of ginseng with radiation significantly alters the biochemical parameters in liver and serum. A significant decline in ACP, ALP activity and LPO content in liver and SGOT and SGPT activity in serum was observed. However, a significant increase in GSH content and LDH activity in liver and ALP activity in serum was estimated. The present study suggests that pretreatment of ginseng before irradiation significantly protects the liver and maintains the enzyme activity.

Development of Alkaline Degreasing Agent for Electroplating Pretreatment Process (도금 전처리공정에서 맞춤형 알칼리계 탈지제 개발)

  • Lee, Seung-Bum;Joeng, Koo-Hyung;Lee, Jae-Dong
    • Applied Chemistry for Engineering
    • /
    • v.21 no.3
    • /
    • pp.301-305
    • /
    • 2010
  • In this study, the alkaline degreasing agent was developed for electroplating pretreatment process, and the efficiency and the durability was predicted. The alkaline deeping degreasing agent was prepared by blending sodium hydroxide (NaOH), sodium carbonate ($Na_2CO_3$), sodium silicate ($Na_2SiO_3$), and sodium lauric sulfate (SLS). The performance tests of the degreasing agent were evaluated in the $40{\sim}50^{\circ}C$ of the degreasing temperature and 30~40 min of the degreasing time. The efficiency and durability of the prepared degreasing agent were tested by the waterdrop formation test and Hull-cell plating test. The optimum ratio of alkaline degreasing agent was NaOH (30 g/L) + SLS (6.0 g/L) + $Na_2SiO_3$ (2.0 g/L) + $Na_2CO_3$ (40 g/L). Also, the optimum degreasing conditions were $50^{\circ}C$ of the degreasing temperature and 35 min of the degreasing time.

Copper Electroplating on Mg Alloy in Pyrophosphate Solution

  • Van Phuong, Nguyen;Moon, Sungmo
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 2016.11a
    • /
    • pp.124.1-124.1
    • /
    • 2016
  • In this work, uniform thickness and good adhesion of electrodeposited copper layer were achieved on AZ91 Mg alloy in alkaline noncyanide copper solution containing pyrophosphate ion by employing appropriate zincate pretreatment. Without zincate pretreatment, the electrodeposited copper layer on AZ91 Mg alloy was porous and showed poor adhesion which was explained by small number of nucleation sites of copper due to rapid dissolution of the magnesium substrate in the pyrophosphate solution. The zincate pretreatment was found as one of the most important steps that can form a conducting layer to cover AZ91 surface which decreased the dissolution rate of AZ91 Mg alloy about 40 times in the copper pyrophosphate solution. Electrodeposited copper layer on AZ91 Mg alloy after an appropriate zincate pretreatment showed good adhesion and uniform thickness with bright surface appearance, independent of the deposition time but the surface roughness of the electrodeposited copper layer increased with increasing Cu deposition time.

  • PDF

High-rate Anaerobic Co-digestion of Food Waste and Sewage Sludge (음식물쓰레기와 하수슬러지의 고율 혐기성 통합소화)

  • Heo, Nam-Hyo;Chung, Sang-Soon
    • New & Renewable Energy
    • /
    • v.1 no.2 s.2
    • /
    • pp.60-72
    • /
    • 2005
  • The effect of alkaline pre-treatment on the solubilization of waste activated sludge(WAS) was investigated, and the biodegradability of WAS, pretreated WAS, [PWAS], food waste and two types of mixture were estimated by biochemical methane potential [BMP] test at $35^{\circ}C$. The biodegradability of PWAS and mixture waste were significantly improved due to the effect of alkaline hydrolysis of WAS. An alkaline pre-treatment was identified to be one of the useful pre-treatment for improving biodegradability of WAS and mixture waste. In high-rate anaerobic co-digestion system coordinate with an alkaline pre-treatment in process, the digesters were operated at the HRT of 5, 7, 10 and 13 days with a mixture of FW $50\%\;and\;PWAS\;50\%,\;$In term of $CH_4$ content, VS removal and specific methane production [SMP] which are the parameters in the performance of digester, the optimum operating condition was found to be a HRT of 7 days and a OLR of 4.20g/L-day with the highest SMP of 0.340 L $CH_4/g$ VS.

  • PDF

Studies on the Antidotal Effect of Panax ginseng The Therapeutic Effect of Ginseng on the Acute Alcoholism (인삼의 해독작용에 관한 연구 급성 알코을 중독에 대한 인삼의 치료 효과)

  • 신만륜
    • Journal of Ginseng Research
    • /
    • v.1 no.1
    • /
    • pp.59-78
    • /
    • 1976
  • In order to investigate the influences of Panax ginseng (white ginseng and red ginseng) on the anesthetic effect and toxic effect of alcohol, experimental studies .had been carried out with albino rabbits, mongolian dogs and mice. The anesthetic effect of alcohol was observed by measuring the induction time, .anesthetic time, recovery time and duration from the beginning of induction to , the recovery of anesthesia (total time), respectively. and toxic effect ($LD_{50}$) of alcohol was measured. In addition to these experiments, al cohol concentration in .blood, blood sugar level, serum transaminase (GOT and GPT) activities and serum alkaline phosphatase activity were measured. Also in order to study the clinical effect of alcohol in healthy students, code .substitution, response time and muscle coordination were tested. The results were obtained as follows. 1. In the rabbits and mongolian Jags, the induction time of anesthesia by the administration of alcohol was delayed by the pretreatment of ginseng but recovery time and total time of anestksia were markedly shortend. 2. The bleed alcohol concentration was decreased by the pretreatment of ginseng , but not affected in mongolian dogs. 3. The blood sugar level, serum transaminase (GOT and GPT) activities and alkaline phoshatase activity in rabbits and dogs induced by the administration of alcohol were affected by the Pretreatment of ginseng. Because those were included within normal ranges, the differnces have no remarkable significance. 4. Liver alcohol dehydrogenase activity of rabbit was increased by the treatment of ginseng, especially it was markedly increased by the treatment of red ginseng 5. The average lethal dose of alcohol to mice was increased by the pretreatment. of ginseng, especially it was markedly increased by the pretreatment of red .ginseng. 6. In the clinical experiments, the blood alcohol concentration induced by alcohol administration was not affected by the pretreatment of ginseng whereas the bleed sugar level was increased. Blood alcohol concentration and bleed sugar level were measured after three hours alcohol administration. 7. The response time of healthy students administered with alcohol was markedly shortened by the pretreatment of ginseng but the experiments on the code substitution and muscle coordination were not affected.

  • PDF