Distribution and biodegradation of polycyclic aromatic hydrocarbons in contaminated sites of Hisar (India).

Fifty-two soil samples were collected from various location of the Hisar city. These samples were analysed for six polycyclic aromatic hydrocarbons (naphthalene, acenaphthene, phenanthrene, anthracene, fluoranthene, and pyrene). Total mean concentration of six PAHs varied from 51.79 to 148.82 mg kg(-1) dry weight of the soil, PAH concentration was higher in soil samples from local auto market while lower concentration was recorded in agricultural soil. Effect ofpH (5.0 to 9.0), temperature (20 degrees to 40 degrees C), and concentration of PAHs (5 to 20 mg kg(-1)) on biodegradation were optimized. Biodegradation of phenanthrene (3-ring) and pyrene (4-ring) was evaluated using two acclimatized microbial strains Pseudomonas putida and Pseudomonas paucimobilis. Biodegradation was maximum in sterilized artificial spiked soil with phenanthrene (5 mg kg(-1)) and pyrene (5 mg kg(-1)) at pH 7.0 and at 30 degrees C (optimized conditions) than the native unsterilized contaminated soil (without optimized conditions) in 42 days of incubation period with Pseudomonas putida and Pseudomonas paucimobilis. Phenanthrene was completely disappeared after 28 days with P. putida and after 35 days with P. paucimobilis. Whereas, pyrene was disappeared up to 97.40% with P. putida and 95.5% with P. paucimobilis after 42 days incubation period at optimum conditions. Under unoptimized conditions, disappearance of phenanthrene was 65.89% with P. putida and 57.81% with P. paucimobilis after 42 days, whereas the % disappearance of pyrene was 59.80% with P. putida and 52.07% with P. paucimobilis.

Biosorption of Cr (VI) with Trichoderma viride immobilized fungal biomass and cell free Ca-alginate beads.

Ability of Cr (VI) biosorption with immobilized Trichoderma viride biomass and cell free Ca-alginate beads was studied in the present study. Biosorption efficiency in the powdered fungal biomass entrapped in polymeric matric of calcium alginate compared with cell free calcium alginate beads. Effect of pH, initial metal ion concentration, time and biomass dose on the Cr (VI) removal by immobilized and cell free Ca-alginate beads were also determined. Biosorption of Cr (VI) was pH dependent and the maximum adsorption was observed at pH 2.0. The adsorption equilibrium was reached in 90 min. The maximum adsorption capacity of 16.075 mgg(-1) was observed at dose 0.2 mg in 100 ml of Cr (VI) solution. The high value of kinetics rate constant Kad (3.73 x 10(-2)) with immobilized fungal biomass and (3.75 x 10(-2)) with cell free Ca- alginate beads showed that the sorption of Cr (VI) ions on immobilized biomass and cell free Ca-alginate beads followed pseudo first order kinetics. The experimental results were fitted satisfactory to the Langmuir and Freundlich isotherm models. The hydroxyl (-OH) and amino (-NH) functional groups were responsible in biosorption of Cr (VI) with fungal biomass spp. Trichoderma viride analysed using Fourier Transform Infrared (FTIR) Spectrometer.

Biodegradation of pulp and paper mill effluent using anaerobic followed by aerobic digestion.

An experimental study was carried to find out the degradability of black liquor of pulp and paper mill wastewater for biomethanogenesis in continuous stirred tank reactor (CSTR) and followed by activated sludge process (ASP). Continuous stirred tank reactor was used in present study for anaerobic digestion of black liquor, while completely mixed activated sludge system was used for aerobic digestion. A maximum methane production was found up to 430 ml/day, chemical oxygen demand was reduced up to 64% and total volatile fatty acid increased up to 1500 mg/l from 975 mg/l at 7.3 pH, 37 degrees C temperature and 8 days hydraulic retention time during anaerobic digestion. In activated sludge process (aerobic digestion) chemical oxygen demand and biological oxygen demand reduction were 81% and 86% respectively at 72 hr hydraulic retention time.