• Title/Summary/Keyword: Alkali and Acid Treatments

Search Result 43, Processing Time 0.027 seconds

Physicochemical Changes of Swine Manure by the Treatment of Acid and Alkali for Inactivation of Pathogenic Microorganisms (병원성미생물의 불활성화를 위한 산·알칼리처리가 양돈분뇨의 이화학적 성상에 미치는 영향)

  • Kim, Cho-Long;Kim, Soo-Ryang;Kim, Ha-Je;Jeon, Sang-Joon;Han, Ho;Kim, Dong-Kyun;Lee, Myung-Gyu
    • Journal of Animal Environmental Science
    • /
    • v.18 no.3
    • /
    • pp.229-234
    • /
    • 2012
  • Disinfecting contaminated swine manure with FMD (Foot-and-Mouth Disease) and pathogenic viruses is very important for maintaining sanitized environment. However, very few research reported on this subject, especially post-disinfection to utilize the wastes as a renewable resource. This research is carried out to obtain basic information for chemical treatment in FMD SOP (Standard Operating Procedure, Korea) of contaminated swine manure. Using lime, sodium hydroxide, citric acid and hydrochloric acid, described in FMD SOP, the effects of chemical treatments on livestock manure were compared in this paper. Four combinations of alkali-acid treatments and four kinds of acid-alkali combinations were tested to find out the effective method. Total coliform bacteria in contaminated swine manure, $1.6{\times}10^4$ CFU/100 ml, decreased to the range of 1/1000~1/100 in all treatments. Some specific disinfectants increases BOD (Biochemical Oxygen Demand) and EC(Electric Conductivity), especially, alkaline treatments increases ammonia level than acid treatments. These findings suggest that the treatment methods should be considered as an important environmental factor in post-disinfection of contaminated animal manure with pathogenic microorganisms.

Double treated mixed acidic solution texture for crystalline silicon solar cells

  • Kim, S.C.;Kim, S.Y.;Yi, J.S.
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2010.02a
    • /
    • pp.323-323
    • /
    • 2010
  • Saw damage of crystalline silicon wafer is unavoidable factor. Usually, alkali treatment for removing the damage has been carried out as the saw damage removal (SDR) process for priming the alkali texture. It usually takes lots of time and energy to remove the sawed damages for solar grade crystalline silicon wafers We implemented two different mixed acidic solution treatments to obtain the improved surface structure of silicon wafer without much sacrifice of the silicon wafer thickness. At the first step, the silicon wafer was dipped into the mixed acidic solution of $HF:HNO_3$=1:2 ration for polished surface and at the second step, it was dipped into the diluted mixed acidic solution of $HF:HNO_3:H_2O$=7:3:10 ratio for porous structure. This double treatment to the silicon wafer brought lower reflectance (25% to 6%) and longer carrier lifetime ($0.15\;{\mu}s$ to $0.39\;{\mu}s$) comparing to the bare poly-crystalline silicon wafer. With optimizing the concentration ratio and the dilution ratio, we can not only effectively substitute the time consuming process of SDR to some extent but also skip plasma enhanced chemical vapor deposition (PECVD) process. Moreover, to conduct alkali texture for pyramidal structure on silicon wafer surface, we can use only nitric acid rich solution of the mixed acidic solution treatment instead of implementing SDR.

  • PDF

Automatic pH Control of Nutrient Solution by Physiological Fertilizers in Lettuce Hydroponics (상추 수경재배시 생리적 산, 알칼리를 이용한 배양액 pH의 자동 조절)

  • 김혜진;김영식
    • Journal of Bio-Environment Control
    • /
    • v.5 no.2
    • /
    • pp.145-151
    • /
    • 1996
  • The effectiveness of physiological or chemical acid - alkali solution was investigated as the method to control pH value of nutrient solution in hydroponics dynamically. Lettuces were cultivated using NH$_4$H$_2$PO$_4$ as physiological acid and NaNO$_3$ as physiological alkali or H$_2$SO$_4$ as chemical acid in dynamic control system. The pH of nutrient solution was controlled satisfactorily in the range of pH 5.5-6.5, regardless of treatments. Chemical acid changed pH of solution faster than chemical acid when supplied to the nutrient solution. Any of them did not show any harmful symptom. It is recommended that chemical acid is preferred during the growing stage and physiological acid like as NH$_4$H$_2$PO$_4$ is preferred from several days before harvest stage.

  • PDF

Extraction Yield and Quality Attributes of Agar from Domestic Seaweeds According to Various Pretreatments (국산원조(國産原藻)의 전처리(前處理)과정에 따른 한천(寒天)의 수율(收率) 및 품질특성(品質特性))

  • Lee, Su-Rae;Cho, Han-Ok;Park, Sang-Ki
    • Korean Journal of Food Science and Technology
    • /
    • v.7 no.3
    • /
    • pp.109-114
    • /
    • 1975
  • Domestic seaweeds Gracilaria verrucosa collected from coastal areas of Namhae, Wando and Yeosoo, Korea were subjected to the examination of yield and quality of agar prepared according to various pretreatment conditions. In alkali treatment at high temperature, higher alkali concentration for one-hour period at $90^{\circ}C$ gave rise to higher yield of agar. In acid treatment, higher yield was obtained by higher acid concentration and longer treating period. Alkali treatment at room temperature gave rise to a slightly decreased yield at higher alkali concentration and longer treating time. Total nitrogen and crude ash of agar samples were greatly decreased by pretreatments. Jelly strength, gelation ability, gelation point and viscosity of agar samples tended to increase as the alkali-treating condition of seaweed became stronger. It was shown that sulfur content of agar had a high negative correlation with jelly strength of its gel. Various alkali treatments of seaweed at room temperature showed no marked difference in agar quality and did not exhibit any good effect comparable to alkali treatment at high temperature.

  • PDF

Quantification of Karanjin, Tannin and Trypsin Inhibitors in Raw and Detoxified Expeller and Solvent Extracted Karanj (Pongamia glabra) Cake

  • Panda, A.K.;Sastry, V.R.B.;Kumar, A.;Saha, S.K.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.19 no.12
    • /
    • pp.1776-1783
    • /
    • 2006
  • Despite being a rich source of protein (28-34%), karanj (Pongamia glabra) cake is found to be bitter in taste and toxic in nature owing to the presence of flavonoid (karanjin), tannin and trypsin inhibitor, thereby restricting its safe inclusion in poultry rations. Feeding of karanj cake at higher levels (>10%) adversely affected the growth performance of poultry due to the presence of these toxic factors. Therefore, efforts were made to detoxify karanj cake by various physico-chemical methods such as dry heat, water washing, pressure cooking, alkali and acid treatments and microbiological treatment with Sacchraromyces cerevisiae (strain S-49). The level of residual karanjin in raw and variously processed cake was quantified by high performance liquid chromatography and tannin and trypsin inhibitor was quantified by titrametric and colorimetric methods, respectively. The karanjin, tannin and trypsin inhibitor levels in such solvent and expeller pressed karanj cake were 0.132, 3.766 and 6.550 and 0.324, 3.172 and 8.513%, respectively. Pressure-cooking of solvent extracted karanj cake (SKC) substantially reduced the karanjin content at a cake:water ratio of 1:0.5 with 30-minute cooking. Among chemical methods, 1.5% (w/w) NaOH was very effective in reducing the karanjin content. $Ca(OH)_2$ treatment was also equally effective in karanjin reduction, but at a higher concentration of 3.0% (w/w). A similar trend was noticed with respect to treatment of expeller pressed karanj cake (EKC). Pressure cooking of EKC was effective in reducing the karanjin level of the cake. Among chemical methods alkali treatment [2% (w/w) NaOH] substantially reduced the karanjin levels of the cake. Other methods such as water washing, dry heat, HCl, glacial acetic acid, urea-ammoniation, combined acid and alkali, and microbiological treatments marginally reduced the karanjin concentration of SKC and EKC. Treatment of both SKC and EKC with 1.5% and 2.0% NaOH (w/w) was the most effective method in reducing the tannin content. Among the various methods of detoxification, dry heat, pressure cooking and microbiological treatment with Saccharomyces cerevisiae were substantially effective in reducing the trypsin inhibitor activity in both SKC and EKC. Based on reduction in karanjin, in addition to tannin and trypsin inhibitor activity, detoxification of SKC with either 1.5% NaOH or 3% $Ca(OH)_2$, w/w) and with 2% NaOH were more effective. Despite the effectiveness of pressure cooking in reducing the karanjin content, it could not be recommended for detoxification because of the practical difficulties in adopting the technology as well as for economic considerations.

A Study on Characteristics of Coated Films on Wood Surface by Nitrocellulose Lacquer, Aminoalkyd, Polyester, and Polyurethan (니트로셀룰로오스락카, 아미노알키드, 폴리에스테르 및 폴리우레탄 도료(塗料)의 도막성능(塗膜性能)에 관(關)한 고찰(考察))

  • Lee, Phil-Woo;Kim, Hyun-Joong
    • Journal of the Korean Wood Science and Technology
    • /
    • v.17 no.1
    • /
    • pp.12-21
    • /
    • 1989
  • This experiment was executed to investigate the characteristics of gloss and color difference in coated films by N.C. Lacquer, Aminoalkyd, Polyester. and Polyurethan coating after chemical (distilled water, ethyl alcohol. acetic acid, and sodium hydroxide) and heating ($120^{\circ}C$) treatments, cold-check test, and U.V. radiation. The results obtained were summarized as follows 1. The gloss decreasing rate by water resistance test was the least among chemicals treated on coated films. 2. The color difference of coated films chemical treatments highly and similarly increased, except the alkali treatment showing a little increase. 3. In the color difference by U.V. radiation, the polyester coated film showed generally large difference compared with the other coated films.

  • PDF

Electrochemical Performance of Activated Carbon Electrode Materials with Various Post Treatments for EDLC (활성탄의 후 처리에 의한 EDLC 전극재의 전기화학 성능 개선)

  • Lee, Eunji;Kwon, Soon Hyung;Choi, Pooreum;Jung, Ji Chul;Kim, Myung-Soo
    • Korean Journal of Materials Research
    • /
    • v.24 no.6
    • /
    • pp.285-292
    • /
    • 2014
  • Commercial activated-carbon used as the electrode material of an electric double-layer capacitor (EDLC) was posttreated with various acids and alkalis to increase its capacitance. The carbon samples prepared were then heat-treated in order to control the amount of acidic functional groups formed by the acid treatments. Coin-type EDLC cells with two symmetric carbon electrodes were assembled using the prepared carbon materials and an organic electrolyte. The electrochemical performance of the EDLC was measured by galvanostatic charge-discharge, cyclic voltammetry, and electrochemical impedance spectroscopy. Among the various activated carbons, the carbon electrodes (CSsb800) prepared by the treatments of coconutshell-based carbon activated with NaOH and $H_3BO_5$, and then heat treated at $800^{\circ}C$ under a flow of nitrogen gas, showed relatively good electrochemical performance. Although the specific-surface-area of the carbon-electrode material ($1,096m^2/g$) was less than that of pristine activated-carbon ($1,122m^2/g$), the meso-pore volume increased after the combined chemical and heat treatments. The specific capacitance of the EDLC increased from 59.6 to 74.8 F/g (26%) after those post treatments. The equivalent series resistance of EDLC using CSsb800 as electrode was much lower than that of EDLC using pristine activated carbon. Therefore, CSsb800 exhibited superior electrochemical performance at high scan rates due to its low internal resistance.

Use of Chemical Treatments to Reduce Tannins and Trypsin Inhibitor Contents in Salseed (Shorea robusta) Meal

  • Mahmood, S.;Khan, Ajmal M.;Sarwar, M.;Nisa, M.;Lee, W.S.;Kim, S.B.;Hur, T.Y.;Lee, H.J.;Kim, H.S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.20 no.9
    • /
    • pp.1462-1467
    • /
    • 2007
  • This study investigated the effect of chemical treatments on tannins (condensed and hydrolysable) and on the trypsin inhibitor (TI) activity in salseed meal. Triplicate samples of ground salseed meal (1 kg) were mixed with 820 ml of either distilled water (pH 5.3), 0.67 M acetic acid (pH 2.4), 0.67 M sodium bicarbonate (pH 8.2) or 2% polyvinyl-pyrrolidone (PVP) solution. The material was placed in airtight plastic containers and incubated at $37^{\circ}C$ for 0, 3, 6, 12, 24, 48 and 72 h. Samples of untreated salseed meal which had not been subjected to soaking or incubation were run through the analysis to serve as control. Addition of water, acetic acid, sodium bicarbonate and PVP solutions to salseed meal and subsequent anaerobic incubation at $37^{\circ}C$ significantly reduced chemically detectable tannins. At each incubation time, alkali solution was more effective than its counterparts. The effect of acidic solution on hydrolysable tannin was least among the treatments. All the treatments reduced TI activity of salseed meal. The reduction in TI activity by these treatments was similar and ranged between 80-84%. Treatment time effected a decrease in the contents of antinutritional substances. However, the effect of the treatment with the reagents, even for zero incubation time, was quite pronounced. It may be concluded from the present results that the treatment of salseed meal with sodium bicarbonate (0.67 M) is more effective in reducing hydrolysable and condensed tannin contents than PVP, water and acid solutions. Treatment with sodium bicarbonate solution is more economical and easier to handle than acid and PVP treatments. Incubation of the treated material for 12 h is reasonably effective, economical and safe from any mould growth.

Effects of Environmentally Friendly Agents on Growth Performance, Nutrient Digestibility, Nutrient Excretion and Carcass Characteristics in Growing-Finishing Pigs

  • Min, T.S.;Kim, J.D.;Hyun, Y.;Sohn, K.S.;Heo, K.N.;Han, In K.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.14 no.4
    • /
    • pp.540-547
    • /
    • 2001
  • An experiment was conducted to investigate the effects of environmentally friendly agents (yucca extract, mineral feed additive, acidifier, nonspecific immunostimulating anionic alkali solution) on the growth performance, nutrient digestibility, nutrient excretion and carcass characteristics in growing-finishing pigs. A total of 125 pigs were allotted into 5 treatments with 5 replications, 5 pigs per pen in a completely randomized block design. Dietary treatments consisted of 1) control: basal diet, 2) YE: basal diet+120 mg/kg of yucca extract, 3) MFA: basal diet+50 mg/kg of mineral feed additive, 4) NIS: basal diet+3% of NIS (nonspecific immunostimulating anionic alkali solution), and 5) Acidifier: basal diet+0.5% of acidifier (organic acid complex). During the growing phase of the feeding trial, There were no significant differences in average daily feed intake (ADFI) and feed conversion ratio (F/G) among treatments, but the Acidifier group showed higher average daily gain (ADG) than the MFA group (p<0.05). During the finishing phase, there were no significant differences in growth performance among treatments, however YE supplementation increased ADG and F/G by 3.1 and 6.15%, respectively, when compared to control group. Proximate nutrients (dry matter, DM; crude protein, CP; crude ash, CA; crude fat, CF; gross energy, GE; calcium, Ca and phosphorus, P) digestibility did not show any significant differences among the treatments. And there were no significant differences in DM, N and P excretion as well. The supplementation of environmentally friendly agents tended to increase carcass weight compared to control group. Pigs fed MFA showed significantly heavier (p<0.05) carcass weight than those fed control or Acidifier diets. Addition of these agents except for NIS to diet for growing-finishing pigs caused a similar feed cost/kg weight gain than control group. Therefore, present study suggested that the optimum environmentally friendly agent would be yucca extracts, considering the effects on growth performance, nutrient digestibility, nutrient excretion, carcass characteristics and feed cost in growing-finishing pigs.

Utilization of Pine Bark (Part 7) -Applicability of Spent Liquor Obtained from Alkaline Sulfite-Anthraquinone (AS-AQ) Cooking of Pine Bark as a Deinking Agent- (소나무 수피의 총합적 이용(제7보) -소나무 수피 AS-AQ 증해폐액의 탈묵제로서의 적용 가능성-)

  • 문성필;박성천
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.33 no.4
    • /
    • pp.42-48
    • /
    • 2001
  • The spent liquor (BSL) obtained from alkaline sulfite-anthraquinone (AS-AQ) cooking of pine bark was applied as a deinking agent. In the ONP deinking system, although BSL removed the small size of ink particles (${\geq}$$12.5{\mu}m$), it did not improve the brightness of pulp. The brightness of pulp slightly improved when treated with BSL at 150~$180^{\circ}C$. However, the brightness of the pulp was lower than that of a commercial deinking agent (oleic acid). It seems that BSL treated with a high temperature still had a high dispersing ability on the ink particles. Intensive oxidations were introduced, and remarkable deinking effects were observed at 13kgf/$cm^2$ oxygen pressure, $160^{\circ}C$ and 2h. When BSL treated at 13kgf/$cm^2$ oxygen pressure, $170^{\circ}C$ and a time period of 30~90 min is added to the pulp, at 0.1% or lower, the deinking effect became higher than that of oleic acid. On the other hand, additional alkali treatments during the oxidation possibility as a deinking agent when oxidized. However, since the oxidized BSL still has a high dispersing ability and lower molecular weight, several modifications need to be done in the near future in order to be applied as a high quality deinking agent.

  • PDF