KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/kmitl/1

Browse

Settings

Author: search.filters.author.Thiravetyan, Paitip

Search Results

Now showing 1 - 2 of 2
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Comparison of bioremediation and phytoremediation in treatment of diethylene glycol from stationery industry
    (2017-01-01)
    Teamkao, Pattrarat
    ;
    Techkarnjanaruk, Somkiet
    ;
    Kullavanijaya, Pratin
    ;
    Thiravetyan, Paitip
    Diethylene glycol (DEG) was found to contaminate wastewater from the stationery industry. The wastewater, after chemical precipitation, still had high DEG and Chemical oxygen demand (COD) resulting in undischarge according to the standard wastewater policy. Bioremediation and phytoremediation were chosen to solve this problem. Comparison of bioremediation and phytoremediation revealed that adding nutrient rich microorganisms removed more DEG, but less COD than using plants grown under hydroponic conditions. However, the bioremediation system had lower potential than plant + soil conditions. The application of a plant-soil system as a constructed wetland was able to remove all DEG (1,500 mg/L) in the wastewater within 8 d. The potential of a constructed wetland system can be enhanced by the addition of microorganisms and nutrients, reducing the time of remediation from 8 to 5 d. In addition, COD reduction to 110 mg/L was reduced from 14 to 11 d, which was lower than the acceptable level (COD ≤ 120 mg/L). However, the use of microorganisms alone cannot reduce COD in contaminated wastewater to the acceptable level. Using constructed wetland with the addition of microorganisms and nutrients is an effective way to remediate DEG and COD from stationery industry wastewater.
      1
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Possible mechanism of gallium bioleaching from gallium nitride (GAN) by Arthrobacter creatinolyticus: Role of amino acids/peptides/proteins bindings with gallium
    (2016-09-01)
    Maneesuwannarat, Sirikan
    ;
    Teamkao, Pattrarat
    ;
    Vangnai, Alisa S.
    ;
    Yamashita, Mitsuo
    ;
    Thiravetyan, Paitip
    The objectives of this work were to screen and characterize heterotrophic bacteria for gallium nitride (GaN) leaching; and to study the involved mechanism of bacterial leaching of Ga from GaN. Ga in the form of GaN has been extensively used as a semiconductor substrate material. The advantage of bioleaching for gallium recovery is the fact that it is a safer, environmentally-friendly method and includes energy-saving processes, which can leach metals at relatively low concentrations. Three bacterial isolates were isolated from cadmium-, and arsenic-contaminated soil in the presence of GaN. NKS4 showed the highest efficiency in Ga leaching at approximately 18% after 15 days, and the system pH was 9. The analysis of 16S rDNA sequences indicated that strain NKS4 was characterized and identified as Arthrobacter creatinolyticus (A. creatinolyticus). Further investigation revealed that the ability of Ga leaching from GaN by this bacterium involved amino acids. Fourier transform infrared spectroscopy (FTIR) was used to investigate the interaction of Ga and amino acids/peptides/proteins which were secreted from this bacteria.
      2