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Article: New bleaching agents for mechanical pulps: a discovery made possible by the pursuit of green chemistry.
- Article from:
- Canadian Chemical News
- Article date:
- April 1, 2004
- Author:
CopyrightCOPYRIGHT 2004 Chemical Institute of Canada. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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In 2000, the Canadian pulp and paper industry contributed over $21 billion to Canada's $54 billion merchandise trade balance and directly employed about 67,000 people. Technical innovation in processes used for the production of pulp and paper will have a significant impact on the Canadian economy.
Canada--the world's biggest producer of mechanical pulp
To make paper, wood (in the form of wood chips or sawmill residue) is first converted to chemical or mechanical pulp by a pulping process. Chemical pulp is produced in a yield of 45 to 55 percent through the dissolution of wood lignin by pulping chemicals, for example, NaOH and [Na.sub.2]S, at elevated ...