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Hemicellulose from dissolving pulp alkali extraction liquid was used as material for furfural production catalyzed by ZSM-5. Reaction temperature have significantly effect on furfural production. The optimal conditions for furfural production were 180 ºC, 1.5 g ZSM-5, 30 mL toluene for 2 h. Under the optimal conditions, furfural yield was 40.18%. When alkali extraction hemicellulose was hydrolyzed by enzyme (xylanase dosage 0.50 mL/g, 50ºC, 18 h) prior to ZSM-5 hydrolysis for furfural formation. The maximum furfural yield of 74.68% was achieved under the best reaction conditions. Furfural yield was effectively improved by enzyme hydrolysis of hemicellulose with high molecular weight.

Acinetobacter sp. SFA 10 was isolated from river water and found to remove ammonium at 5 °C. The ammonium removal rate was 2.05 mg NH₄⁺-N/l/h when the initial ammonium concentration was about 5 mg/l. When the initial ammonium concentration was higher than 45 mg/L, the ammonium removal rate of Acinetobacter sp. SFA 10 decreased. With the ammonium removing by Acinetobacter sp. SFA 10, NH₂OH was produced without nitrite or nitrate accumulation. Ammonia monooxygenase (AMO) and hydroxylamine oxidase (HAO) were the key enzyme for nitrification. In Acinetobacter sp. SFA 10 cells, amo andhao genes were amplified and about 600bp. Nitrate reductase gene (napA), nitrite and nitrate reductase enzymes were not detected in Acinetobacter sp. SFA 10. The results in this study showed that Acinetobacter sp. SFA 10 oxidized ammonium to NH₂OH, then convert NH₂OH to nitrate. Acinetobacter sp. SFA 10 didn't have the ability of denitrification.