Three dispersion instruments (a standard laboratory disintegrator, PFI beater, and ultrasonic cell disrupter) were tested to determine their effects on the dispersion of bacterial cellulose (BC) wet films. After treatment with a standard 10000 r disintegrator treatment, there was still a large number of undispersed fiber bundles in the BC suspension. The BC films were dispersed well after PFI beating revolution at 30000 r, and the cationic charge demand of the BC suspension reached 2.4 × 10 -4 eq·g -1 . The ultrasonic cell crusher was altogether unsuitable for BC dispersion. The ultrasonic cell crusher only separated the BC from the bundles. The properties of the resulting paper indicated that the physical strength of paper containing BC dispersed by the PFI beater was higher than that of the sample produced via standard laboratory disintegrator. Well-dispersed BC was distributed evenly among the plant fibers, which benefitted the combination of BC and plant fiber to improve the physical properties of the paper sheets.

Unbleached kraft bamboo pulp was pretreated by a xylanase and laccase (X/L) treatment, as well as a joint treatment of X/L and alkali, prior to element chlorine free (ECF) bleaching. In comparison with the control test, the joint treatment of X/L and alkali (X/L+0.1%) had more potential to reduce absorbable organic halide (AOX) levels (29.79%) and COD content (21.55%), in addition to improving bleached pulp properties (56.88% decrease in kappa number and 8.94 %ISO increased in brightness). Moreover, the treatment of X/L+0.1% removed more lignin and HexA than X/L treatment. The analysis of XPS indicated that the X/L treatment could noticeably remove the surface lignin of pulp, but the joint treatments of X/L and alkali could promote the production of superficial lignin. FTIR results showed that pretreatments only reduced part of the lignin and carbohydrate contents, but did not change their structures. The joint pretreatment of enzymes and diluted alkali (X/L+0.1%) had more appealing advantages to produce bleached kraft bamboo pulp.

Bacterial cellulose is a common research additive in the paper industry because it has unique and favorable characteristics. In this study, the effect of adding bacterial cellulose to an alkyl ketene dimer (AKD) sizing agent was investigated to optimize the dosage of bacterial cellulose, the retention system (cationic starch (CS), cationic polyacrylamide (CPAM)), and the sizing enhancement agents (polyamideamine-epichlorohydrin (PAE) and chitosan). The results showed that the addition of bacterial cellulose had a negative effect on AKD sizing. Meanwhile, the addition of 5% bacterial fiber had a slight but negligible effect on paper sizing. The retention system improved AKD sizing and the dual retention system with CS, and CPAM improved sizing up to 60%. When 0.2% PAE and chitosan were added simultaneously, the sizing degree increased by 42.8% and 47.6%, respectively.

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