Totally chlorine-free process

ECF elemental chlorine free process TCF totally chlorine free process TEF totally effluent free process... 

Since it became clear that the direct use of chlorine in the bleaching of pulp and paper leads to highly poisonous chlorinated organic species in the waste water, chlorine dioxide is used instead in the so-called ECF (Elemental Chlorine Free) process. The competing process is the TCF (Total Chlorine Free) process, which uses peroxides [11],... 

Chemical pulp bleaching has undergone significant process changes since around 1990. Until that time, nearly every chemical pulp mill that had used bleaching had incorporated elemental chlorine (Clj) into some of its processes. Because of environmental and health concerns about dioxins, U.S. pulp mills now use elemental chlorine free (ECF) and total chlorine free (TCF) bleaching technologies. The most common types of ECF and TCF are shown in Table 21.5. The difference... 

Common Chemicals Used in Elemental Chlorine Free (ECF) and Total Chlorine Free (TCF) Bleaching Processes... 

TCF [Totally Chlorine-Free] A generic term for pulp-bleaching processes which do not use chlorine in any form. Oxidants and enzymes are used. See also ECF. 

Totally chlorine free bleaching (TCF) technologies, 10 304-305 Totally chlorine-free (TCF) bleaching processes, 21 44... 

Today, the pulp and paper industry operates with two main pulping processes and three bleaching processes. The latter are the chlorine bleaching process, the elementary chlorine-free (ECF) process, and the totally chlorine-free (TCF) process they are compared in Table 6.4. 

Totally chlorine-free (TCF) process. The TCF process uses hydrogen peroxide in the bleaching process. As a drawback, about 10% more wood has to be used for the... 

Why are solid, unmodified alumina, silicas, and zeolites able to be used as catalysts (77) Are lanthanide catalysts really environmentally friendly 18) What are solid acids and solid bases and how can they be used for catalysis 19) Why is catalysis a foundational pillar of green chemistry 20) What are the advantages of a totally chlorine free bleaching process (27)... 

DMC made with this process is totally chlorine-free, whereas the conventional route involves the use of phosgene and methanol. 

Continued promotion of eco-white kraftliner, based on a new process for significantly more efficient wood and fiber utilization plus totally chlorine-free bleaching. Thanks to the improved environmental profile, it has been possible to speed up the market introduction, resulting in additional revenues of several tens of millions of Swedish kronor. 

Then, after the process of disinfection, and after the reactions with reduced organic and inorganic matter (including NH3) take place, the total available chlorine (or total chlorine residual) is given by the sum of the free available chlorine and the combined available chlorine. ... 

Some 90% of the total world PUR market is in foam. Foam results from the formation of gas bubbles in the polymerization process originally these were all CFCs, but the producers are moving rapidly towards chlorine-free blowing agents. There are three distinct types of PUR foam ... 

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