Uma alternativa para a glicerina oriunda da produção do biodiesel : preparo de polióis e aplicação em adesivos poliuretânicos

AUTOR(ES)

Karla Dall Alba

FONTE

IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia

DATA DE PUBLICAÇÃO

2009

RESUMO

This work reports the purification of the residual glycerin, a coproduct of the biodiesel production and their esterification with fatty acids from vegetable oils. The obtained products, mainly monoacylglycerides (polyols), were used for the preparation of urethanic adhesives. Firstly, residual glycerin was purified by vacuum distillation and the acid catalyzed esterification with oleic acid was investigated. Also the enzymatic reaction using Lipases was studied. The reactional conditions and the conversion to monoacylglycerides were similar to those obtained for glycerol P.A, confirming the high purity of the distilled glycerin. In another purification method, the volatile components of the residual glycerin were eliminated by distillation at reduced pressure and the purified glycerin was used to prepare polyols by enzymatic esterification with oleic acid. A yield around 80 % and higher selectivity to monoacylglycerides were reached. Purification of residual glycerin by filtration through active coal, Celite, aluminum oxide and by dialysis was not enough to prepare polyols in good yields either by enzymatic or acid esterification. Polyols obtained from distilled and purified glycerin showed a hydroxyl number between 192-320mg KOH/g. They were used to prepare urethanic adhesives by reaction with polymeric methylenediphenyldiisocyanate (pMDI) at NCO/OH of 0.8 and 1.2. The adhesive properties were investigated by shear measurements in wood specimens and compared with a commercial one. Similar maximal shear stresses were obtained, 3,12 MPa and 3,72 MPa, respectively. Better properties were achieved at NCO/OH ratio of 0.8. Incorporation of 20 %wt of castor oil in the adhesive formulation improved significantly the mechanical properties (shear stress of 5.34 MPa) due to the higher molecular weight of the backbone chain.

ASSUNTO(S)

glicerina poliois adesivos espectroscopia : infravermelho

Documentos Relacionados

• Adesivos poliuretanicos derivados de PET reciclado : sintese, caracterização e aplicação
• Glicerina bruta oriunda da agroindústria do biodiesel na alimentação de cordeiros em terminação
• Avaliação do processo de digestão anaeróbia na geração de energia a partir de dejetos suinos e bovinos de leite com suplementação de glicerina residual bruta oriunda da produção de biodiesel
• Avaliação do processo de digestão anaeróbia na geração de energia a partir de dejetos suinos e bovinos de leite com suplementação de glicerina residual bruta oriunda da produção de biodiesel
• Gliceroquímica: novos produtos e processos a partir da glicerina de produção de biodiesel