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Chemical pulping involves dissolving lignin in order to extract the cellulose from the wood fiber. The different processes of chemical pulping include the Kraft process, which uses caustic soda and sodium sulfide and is the most common; alternatively, the use of sulfurous acid is known as the sulfite process, the neutral sulfite semichemical is treated as a third process separate from sulfite ...
The pulp produced up to this point in the process can be bleached to produce a white paper product. The chemicals used to bleach pulp have been a source of environmental concern, and recently the pulp industry has been using alternatives to chlorine, such as chlorine dioxide, oxygen, ozone and hydrogen peroxide.
The kraft process involves treatment of wood chips with a hot mixture of water, sodium hydroxide (NaOH), and sodium sulfide (Na 2 S), known as white liquor, that breaks the bonds that link lignin, hemicellulose, and cellulose. The technology entails several steps, both mechanical and chemical. It is the dominant method for producing paper.
Recycled paper products can also contain BPA, [65] although this can depend strongly on how it is recycled. Deinking can remove 95% of BPA, [9] with the pulp produced used to make newsprint, toilet paper and facial tissues. If deinking is not performed then the BPA remains in the fibers, paper recycled this way is usually made into corrugated ...
As an example, bisphenol A (a chemical commonly found in thermal paper) has been verified as a contaminant in a variety of paper products resulting from paper recycling. [39] Groups of chemicals as phthalates, phenols, mineral oils, polychlorinated biphenyls (PCBs) and toxic metals have all been identified in paper material. [40]
A new study from Belgian researchers found that paper straws had higher concentrations of long-lasting, water resistant "forever chemicals" than plastic or steel straws.
Sixty-nine percent of the brands contained PFAS, with paper straws more likely to contain the chemicals. The researchers found 90% of paper straws had PFAS, compared to 80% of bamboo straws, 75% ...
The Soviet Union made “extensive use” of the chemical substance during World War II, filling grenades, bombs and missiles with it, according to a 1953 CIA report.