title: Potassium hydroxide pulping of rice straw in biorefinery initiatives.
abstract: Rice straw is supposed to be one of the most important lignocellulosic raw materials for pulp mill in Asian countries. The major problem in rice straw pulping is silica. The present research is focused on the separation of silica from the black liquor of rice straw pulping by potassium hydroxide (KOH) and pulp evaluation. Optimum KOH pulping conditions of rice straw were alkali charge 12% as NaOH, cooking temperature 150°C for 2h and material to liquor ratio, 1:6. At this condition pulp yield was 42.4% with kappa number 10.3. KOH pulp bleached to 85% brightness by D0EpD1 bleaching sequences with ClO2 consumption of 25kg/ton of pulp. Silica and lignin were separated from the black liquor of KOH pulping. The amount of recovered silica, lignin and hemicelluloses were 10.4%, 8.4% and 13.0%. The papermaking properties of KOH pulp from rice straw were slightly better than those of corresponding NaOH pulp.
authors: Pulp and Paper Research Division, BCSIR Laboratories, Dhaka, Dr. Qudrat-i-Khuda Road, Dhaka 1205, Bangladesh. Electronic address: sarwar2065@yahoo.co.uk.
authors: M Sarwar
authors: MS
authors: Jahan
authors: Pulp and Paper Research Division, BCSIR Laboratories, Dhaka, Dr. Qudrat-i-Khuda Road, Dhaka 1205, Bangladesh; Department of Chemistry, Eden Girls College, Dhaka, Bangladesh.
authors: Fahmida
authors: F
authors: Haris
authors: Pulp and Paper Research Division, BCSIR Laboratories, Dhaka, Dr. Qudrat-i-Khuda Road, Dhaka 1205, Bangladesh.
authors: M Mostafizur
authors: MM
authors: Rahman
authors: Department of Chemistry, Eden Girls College, Dhaka, Bangladesh.
authors: Purabi Rani
authors: PR
authors: Samaddar
authors: Pulp and Paper Research Division, BCSIR Laboratories, Dhaka, Dr. Qudrat-i-Khuda Road, Dhaka 1205, Bangladesh.
authors: Shrikanta
authors: S
authors: Sutradhar
mesh_terms: D000468:Alkalies; D002482:Cellulose / Q000737:chemistry*; D006878:Hydroxides / Q000737:chemistry*; D012275:Oryza / Q000737:chemistry*; D017680:Potassium Compounds / Q000737:chemistry*; D012822:Silicon Dioxide; D013696:Temperature
chemical_list: D000468:Alkalies; D006878:Hydroxides; D017680:Potassium Compounds; D012822:Silicon Dioxide; D002482:Cellulose; C029943:potassium hydroxide
keywords: Bleaching; Kappa number; Lignin; Papermaking properties; Potassium hydroxide; Pulp yield; Silica