Tipeng Wang

Effects of biopretreatment on pyrolysis behaviors of corn stalk by methanogen.

The study investigated the effects of methanogen pretreatment on pyrolysis behaviors of corn stalk (CS) by using Py-GC/MS analysis and thermogravimetric analysis. Results indicated that biopretreatment changed considerably the pyrolysis behaviors of CS from four weight loss stages to two weight loss stages. Increasing biopretreatment time from 5 days to 25 days enhanced the kinds and contents of chemicals in volatile products. In pyrolysis products, the contents of sugars, linear ketones and furans decreased from 1.43%, 12.60% and 7.38% to 1.25%, 10.22% and 3.25%, respectively, and the contents of phenols increased from 15.08% to 27.84%. The most content change from 6.83% to 13.63% indicated that methanogen pretreatment improved the pyrolysis selectivity of CS to product the 4-VP, but it was disadvantageous to 5-hydroxymethyl furfural, levoglucose and furfural. The changes of chemical compositions and structure of CS after biopretreatment were the main reason of the differences.

Fast pyrolysis product distribution of biopretreated corn stalk by methanogen.

After pretreated by methanogen for 5, 15 and 25 days, corn stalk (CS) were pyrolyzed at 250, 300, 350, 400, 450 and 500 °C by Py-GC/MS and product distribution in bio-oil was analyzed. Results indicated that methanogen pretreatment changed considerably the product distribution: the contents of sugar and phenols increased; the contents of linear carbonyls and furans decreased; the contents of linear ketones and linear acids changed slightly. Methanogen pretreatment improved significantly the pyrolysis selectivity of CS to phenols especially 4-VP. At 250 °C, the phenols content increased from 42.25% for untreated CS to 79.32% for biopretreated CS for 5 days; the 4-VP content increased from 28.6% to 60.9%. Increasing temperature was contributed to convert more lignin into 4-VP, but decreased its content in bio-oil due to more other chemicals formed. The effects of biopretreatment time on the chemicals contents were insignificant.

Pyrolytic characteristics of sweet potato vine

To utilized biomass for optimum application, sweet potato vine (SPV) was studied on its pyrolytic characteristics by TGA and Py-GC/MS analysis as a representative of biomass with low lignin content and high extractives content. Results indicated that lignin, cellulose, hemicellulose and extractives contents were 7.85 wt.%, 33.01 wt.%, 12.25 wt.% and 37.12 wt.%, respectively. In bio-oil, sugars content firstly increased from 8.76 wt.% (350 °C) to 13.97 wt.% (400 °C) and then decreased to 9.19 wt.% (500 °C); linear carbonyls and linear acids contents decreased from 16.58 wt.% and 17.45 wt.% to 5.26 wt.% and 4.03 wt.%, respectively; furans content increased from 7.10 wt.% to 15.47 wt.%. The content 11.86 wt.% of levoglucose at 400 °C, 15.41 wt.% of acetic acid at 350 °C and 6.94 wt.% of furfural at 500 °C suggested good pyrolysis selectivity of SPV.

Erratum to: Ammonium and phosphate limitation in 1,3-propanediol production by Klebsiella pneumoniae

Following publication of the above article (DOI: 10.1007/s10529-009-0150-y) in the October 2009 issue of Biotechnol Lett (32:289–294), it was found that the author affiliation name had been published incorrectly as: National Engineering Laboratory for Power Generation Equipment, School of Renewable Energy, North China Electric University, Beijing 102206, China The correct author affiliation name is listed below: National Engineering Laboratory for Biomass Power Generation Equipment, School of Renewable Energy, North China Electric Power University, Beijing 102206, China