Process development for cigarette butts recycling into cellulose pulp.
Cigarette butts, which are usually thrown on the ground or into ordinary bins, have been recognized as toxic residues since may contain cigarette contaminants and chemicals produced during combustion. Therefore, contaminants in cigarette butts can be leached by rain into surface water and thereby contaminate the environment. In Brazil, according to the National Policy on Solid Waste, all residues must be disposed of in an environmentally friendly manner. Although cigarette butts are not mentioned in the law, due to their characteristics, they may be classified as hazardous waste. At the University of Brasilia, a cellulose pulp production process from cigarette butts has been developed employing alkaline pulping. This process is presented as an alternative to environmentally friendly final disposal of this residue. During the process, a dark liquor is generated, which was found to contain lignin, carbonyls, metals, nicotine and specific tobacco nitrosamines. The dark liquor was treated by acidification to promote lignin precipitation, coagulation with chitosan and Al2(SO4)3to remove metals and organic compounds and ozonized to oxidize resistant chemicals. The dark liquor presented a high chemical oxygen demand (COD; 29,986mg/L), which was partially removed by precipitation (20%), chitosan coagulation (66%) and ozonation (45.8%). As the remaining COD was still high, we proposed reusing the clarified effluent in alkaline pulping, which seemed to be the easiest and most efficient procedure with the lowest cost.
Laboratório de Materiais e Combustíveis, Instituto de Química, Universidade de Brasília, Cx. Postal 04478, CEP 70904-970 Brasília/DF, Brazil.
Maria Betânia
MB
d'Heni Teixeira
Laboratório de Materiais Expressivos, Instituto de Artes, Universidade de Brasília, CEP 70904-970 Brasília/DF, Brazil.
Marco Antônio B
MAB
Duarte
Laboratório de Materiais Expressivos, Instituto de Artes, Universidade de Brasília, CEP 70904-970 Brasília/DF, Brazil.
Loureine
L
Raposo Garcez
Laboratório de Materiais e Combustíveis, Instituto de Química, Universidade de Brasília, Cx. Postal 04478, CEP 70904-970 Brasília/DF, Brazil.
Joel
J
Camargo Rubim
Laboratório de Materiais Expressivos, Instituto de Artes, Universidade de Brasília, CEP 70904-970 Brasília/DF, Brazil.
Thérèse
T
Hofmann Gatti
Laboratório de Materiais e Combustíveis, Instituto de Química, Universidade de Brasília, Cx. Postal 04478, CEP 70904-970 Brasília/DF, Brazil. Electronic address: psuarez@unb.br.
Paulo Anselmo Ziani
PAZ
Suarez
D001938:Brazil; D002482:Cellulose / Q000032:analysis*; D006256:Hazardous Waste / Q000032:analysis*; D059027:Recycling / Q000379:methods*; D012037:Refuse Disposal / Q000379:methods*; D062789:Tobacco Products / Q000032:analysis*; D018505:Waste Management
D006256:Hazardous Waste; D002482:Cellulose
Cellulose acetate; Cellulose pulp; Cigarette butts; Recycling; Solid waste