MODIFICATION OF SFP LIGNOSULFONATE WITH HYDROGEN PEROXIDE AND UREA TO PREPARE SLOW RELEASE NITROGEN FERTILIZER
SFP (sulfite formaldehyde pulping) lignosulfonate was modified by the reaction with hydrogen peroxide and urea. The effects of reaction time, reaction temperature, pH of reaction medium, hydrogen peroxide dosage, and catalyst dosage on the amount of fixed (organic-bound) nitrogen in the lignosulfonate were investigated. Relatively high nitrogen content was obtained when oxidation and modification occurred simultaneously and the nitrogen content was increased by 50% in comparison with that of the product simply modified with urea without oxidation. Under the conditions of temperature 75℃, hydrogen peroxide 15%, initial pH of the reaction medium 4, reaction time 3 h, and the dosage of Fe2+ 0.02%, 8.6% of nitrogen (based on lignin) could be fixed in the lignin molecules, ammonium nitrogen in modified products was 1.13%. The organic bound nitrogen reached up to 7.5% which would be released slowly through lignin degradation.
SFP lignosulfonate urea slow release nitrogen fertilizer ozidation
Yang Yiqin Li Baoyu Cao Yunfeng Jin Yongcan Li Zhongzheng
College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China Key Laboratory o College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
国际会议
广州
英文
716-721
2006-11-08（万方平台首次上网日期，不代表论文的发表时间）