Pulping Advantages of Zip-lignin Hybrid Poplar, 2016 Pulping, Engineering, Environmental, Recycling, Sustainability (PEERS) Conference Proceedings

Hybrid poplar that has been genetically modified to have chemically labile ester linkages in its lignin backbone (which we refer to as zip-lignin hybrid poplar) was studied to determine if the modifications would enhance kraft pulping efficiencies. Pulping of zip-lignin and wild-type hybrid poplar was carried out in lab-scale reactors under varying conditions, including alkali dosage (active alkali; AA), sodium sulfide dosage (sulfidity; S), and cooking severity (H-factor). The resulting pulps were analyzed for standard pulp properties including yield, residual lignin content (via Kappa number), cellulose DP (via CED viscosity), and carbohydrates (via HPLC). Finally, the ensuing pulp properties were used to create statistical models. Compared to wild-type, the zip-lignin hybrid poplar cooked at identical conditions showed higher delignification, confirming the zip-lignin effect. Additionally, pulp yield and carbohydrates content were slightly elevated, as was the cellulose DP for zip-lignin hybrid poplar. Statistical prediction models created from the data set facilitated comparisons to be made of pulping conditions that result in identical delignification (end of cook Kappa numbers), with the zip-lignin poplar needing milder cooking conditions. The models suggest that using the lower H-factor or AA to achieve a target Kappa would result in higher pulp yield (up to 1.41% gain), as more cellulose and hemicellulose will be preserved. Based on these results, we can conclude that zip-lignin hybrid poplar can be pulped more easily than wild-type hybrid poplar, validating the approach of using zip-lignin technology for the pulp industry.  

TAPPI conference proceedings and presentations, technical papers, and publication articles provide technical and management data and solutions on topics covering the Pulp, Paper, Tissue, Corrugated Packaging, Flexible Packaging, Nanotechnology and Converting Industries.

Simply select the quantity, add to your cart and your conference paper, presentation or article will be available for immediate download.