title: Biosorption of cadmium by fungal biomass of Aspergillus niger.
abstract: OBJECTIVE
  To investigate the removal of cadmium from aqueous solution by waste fungal biomass of Aspergillus niger, originated from citric acid fermentation industry.
  
  
  METHODS
  Batch adsorption test was used to study the biosorption equilibrium and isotherm. The Cd2+ concentration was measured with atomic adsorption spectrophotometer (AAS) HITACHI 180-80.
  
  
  RESULTS
  The biosorption achieved equilibrium within 30 min. The adsorption isotherm could be described by Freundlich adsorption model, and the constants K(F) and 1/n were determined to be 2.07 and 0.18, respectively, and the correlation efficiency was 0.97. The optimal pH for Cd adsorption was 6.0. The cadmium-laden biomass could be effectively regenerated using 0.1 N HCl.
  
  
  CONCLUSIONS
  The waste biomass of Aspergillus niger, a by-product of fermentation industry, is a potential biosorbent for the removal of cadmium from aqueous solution.
authors.affiliation: Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Yang
authors.forename: Jian-Long
authors.initials: JL
authors.lastname: Wang
authors.forename: Zhi
authors.initials: Z
authors.lastname: Xing
mesh_terms: D000327:Adsorption; D001234:Aspergillus niger; D018533:Biomass; D002104:Cadmium / Q000302:isolation & purification*; D019343:Citric Acid; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D007220:Industrial Waste; D014874:Water Pollutants, Chemical; D002104:Cadmium; D019343:Citric Acid