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PRODUCTION OF OXALIC ACID BY ASPERGILLUS NIGER Sri Handayani; Suratman Suratman
Indonesian Mining Journal Vol 12, No 2 (2009): INDONESIAN MINING JOURNAL Vol. 12 No. 2 June 2009
Publisher : Puslitbang tekMIRA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (89.703 KB) | DOI: 10.30556/imj.Vol12.No2.2009.567

Abstract

Oxalic acid has been suggested to be essential in the metal leaching processes by Aspergillus niger. The ability of Aspergillus niger strain to produce a high amount of oxalic acid on glucose and sucrose media was investigated. The experimental results show that glucose is favorable for oxalic acid biosynthesis which can produce 14.47 g/L oxalic acid compared to 7.09 g/L oxalic acid on sucrose medium. The production pattern, however, were identical on both substrates. The main drawback of this fermentation was the low yield attained (75.47 % from theoretical yield) probably because some of glucose was oxidized to gluconic acid at the beginning of fermentation, and due to some limitation of growing the A. niger in shake flask condition because pH of the culture cannot be fully controlled in shake flask system. Therefore, batch culture in fully controlled fermentor can be carried out as further steps of experiment after shake flask.
EFFECTS OF TEMPERATURE AND NUTRIENT FEED ON THE PRODUCTION OF OXALIC ACID BY ASPERGILLUS NIGER SRI HANDAYANI
Indonesian Mining Journal Vol 14, No 3 (2011): INDONESIAN MINING JOURNAL Vol. 14 No. 3 October 2011
Publisher : Puslitbang tekMIRA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (155.623 KB) | DOI: 10.30556/imj.Vol14.No3.2011.482

Abstract

Oxalic acid is an important organic material used for rare earth metal extraction precipitator, metallic equip- ment purificant and purification of industrial minerals. Aspergillus niger is known to be able to produce a high concentration of oxalic acid using glucose as carbon and energy sources. For further process optimiza- tion, submerged fermentation experiments were carried out to study the effect of temperature and nutrient feed on the production of oxalic acid from medium containing glucose 35g/L. An increase in temperature process from 25 to 30°C allowed the productivity to significantly increase from 75.50 to 81.06% of theoretical yield with a final oxalic acid concentration of 17.04 g/L reached after 9 days of process. When operating at more controlled fermentor with fed-batch system, both productivity and oxalic acid concentration were markedly improved (88.01% of theoretical yield and 19.52 g/L respectively). The later system gave excel- lent yield almost 90% of theoretical yield as a prerequisite of economical value.
BENEFICIATION OF SAMBIROTO SILICA SAND BY CHEMICAL AND BIOLOGICAL LEACHINGS Suratman Suratman; Sri Handayani
Indonesian Mining Journal Vol 17, No 3 (2014): INDONESIAN MINING JOURNAL Vol. 17 No. 3 OCTOBER 2014
Publisher : Puslitbang tekMIRA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1987.038 KB) | DOI: 10.30556/imj.Vol17.No3.2014.318

Abstract

The commercial value of silica sand significantly affected by the presence and content of iron, aluminium and other metal impurities that can have detrimental effects on the manufactured product. A leaching technology on Sambiroto silica sand had been studied using chemical (HCl and H2SO4) and biological (Aspergillus niger’s metabolite) methods to remove undesired metal impurities and obtain a high purity silica. The rates and extent of chemical leaching and bioleaching were different depending on the leaching agents used and their concen- trations. The results showed that the laboratory experiments improved the silica sand sample to a high grade purity. The major and minor impurities of Fe, Al, Ca, Cr, Ti, Zr and Cu were reduced significantly by acid leaching with HCl and H2SO4 4M at 90°C, 30% pulp density for 4-hours process. The chemical composition of the silica sand improved with the SiO2 content increased from 97.24 to 98.77%, on the other hand, the sum of impurities decreased from 1.148 to 0.237 %. These changes bring the beneficiated product very close to a feedstock of metallurgical grade silicon for advanced materials. Among the tested methods, chemical leaching is the most efficient in terms of both increasing percentage of SiO2 and metal impurities removal compared to biological leaching. Nevertheless, bioleaching process is sufficient to produce silica sand with a desired minimum value of Fe and Al contents for high quality glass industries. Both process characteristics could facilitate their industrial applications.
BENEFICIATION OF SAMBIROTO SILICA SAND BY CHEMICAL AND BIOLOGICAL LEACHINGS Suratman Suratman; Sri Handayani
Indonesian Mining Journal Vol 17 No 3 (2014): INDONESIAN MINING JOURNAL Vol. 17 No. 3 OCTOBER 2014
Publisher : Balai Besar Pengujian Mineral dan Batubara tekMIRA

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30556/imj.Vol17.No3.2014.318

Abstract

The commercial value of silica sand significantly affected by the presence and content of iron, aluminium and other metal impurities that can have detrimental effects on the manufactured product. A leaching technology on Sambiroto silica sand had been studied using chemical (HCl and H2SO4) and biological (Aspergillus niger’s metabolite) methods to remove undesired metal impurities and obtain a high purity silica. The rates and extent of chemical leaching and bioleaching were different depending on the leaching agents used and their concen- trations. The results showed that the laboratory experiments improved the silica sand sample to a high grade purity. The major and minor impurities of Fe, Al, Ca, Cr, Ti, Zr and Cu were reduced significantly by acid leaching with HCl and H2SO4 4M at 90°C, 30% pulp density for 4-hours process. The chemical composition of the silica sand improved with the SiO2 content increased from 97.24 to 98.77%, on the other hand, the sum of impurities decreased from 1.148 to 0.237 %. These changes bring the beneficiated product very close to a feedstock of metallurgical grade silicon for advanced materials. Among the tested methods, chemical leaching is the most efficient in terms of both increasing percentage of SiO2 and metal impurities removal compared to biological leaching. Nevertheless, bioleaching process is sufficient to produce silica sand with a desired minimum value of Fe and Al contents for high quality glass industries. Both process characteristics could facilitate their industrial applications.
EFFECTS OF TEMPERATURE AND NUTRIENT FEED ON THE PRODUCTION OF OXALIC ACID BY ASPERGILLUS NIGER SRI HANDAYANI
Indonesian Mining Journal Vol 14 No 3 (2011): INDONESIAN MINING JOURNAL Vol. 14 No. 3 October 2011
Publisher : Balai Besar Pengujian Mineral dan Batubara tekMIRA

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30556/imj.Vol14.No3.2011.482

Abstract

Oxalic acid is an important organic material used for rare earth metal extraction precipitator, metallic equip- ment purificant and purification of industrial minerals. Aspergillus niger is known to be able to produce a high concentration of oxalic acid using glucose as carbon and energy sources. For further process optimiza- tion, submerged fermentation experiments were carried out to study the effect of temperature and nutrient feed on the production of oxalic acid from medium containing glucose 35g/L. An increase in temperature process from 25 to 30°C allowed the productivity to significantly increase from 75.50 to 81.06% of theoretical yield with a final oxalic acid concentration of 17.04 g/L reached after 9 days of process. When operating at more controlled fermentor with fed-batch system, both productivity and oxalic acid concentration were markedly improved (88.01% of theoretical yield and 19.52 g/L respectively). The later system gave excel- lent yield almost 90% of theoretical yield as a prerequisite of economical value.
PRODUCTION OF OXALIC ACID BY ASPERGILLUS NIGER Sri Handayani; Suratman Suratman
Indonesian Mining Journal Vol 12 No 2 (2009): INDONESIAN MINING JOURNAL Vol. 12 No. 2 June 2009
Publisher : Balai Besar Pengujian Mineral dan Batubara tekMIRA

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30556/imj.Vol12.No2.2009.567

Abstract

Oxalic acid has been suggested to be essential in the metal leaching processes by Aspergillus niger. The ability of Aspergillus niger strain to produce a high amount of oxalic acid on glucose and sucrose media was investigated. The experimental results show that glucose is favorable for oxalic acid biosynthesis which can produce 14.47 g/L oxalic acid compared to 7.09 g/L oxalic acid on sucrose medium. The production pattern, however, were identical on both substrates. The main drawback of this fermentation was the low yield attained (75.47 % from theoretical yield) probably because some of glucose was oxidized to gluconic acid at the beginning of fermentation, and due to some limitation of growing the A. niger in shake flask condition because pH of the culture cannot be fully controlled in shake flask system. Therefore, batch culture in fully controlled fermentor can be carried out as further steps of experiment after shake flask.
Co-Authors Suratman Suratman