Extraction, preparation and characterization of cellulose fibres and nanocrystals from rice husk

http://jultika.oulu.fi/files/nbnfi-fe2017112150815.pdf

One-part alkali-activated materials : a review

Natural fibers today are a popular choice for applications in composite manufacturing. Based on the sustainability benefits, biofibers such as plant fibers are replacing synthetic fibers in composites. These fibers are used to manufacture several biocomposites. The chemical composition and properties of each of the fibers changes, which demands the detailed comparison of these fibers. The reinforcement potential of natural fibers and their properties have been described in numerous papers. Today, high performance biocomposites are produced from several years of research. Plant fibers, particularly bast and leaf, find applications in automotive industries. While most of the other fibers are explored in lab scales they have not yet found large-scale commercial applications. It is necessary to also consider other fibers such as ones made from seed (coir) and animals (chicken feather) as they are secondary or made from waste products. Few plant fibers such as bast fibers are often reviewed briefly but other p...

A Review of Natural Fibers Used in Biocomposites: Plant, Animal and Regenerated Cellulose Fibers

Biosorption of heavy metals using rice milling by-products. Characterisation and application for removal of metals from aqueous effluents.

Uniformly sized ultrafine silica powder can be obtained by nonisothermal decomposition of rice husk in an oxidizing atmosphere. The properties of reactant and product including morphology, particle size, surface area, pore volume and pore distribution, have been investigated by TEM, SEM, XRD, FTIR, ICP-MS, and EA. At a heating rate of 5 K/min, the specific surface area of the silica powder was 235 m 2 /g, the average pore diameter was 5.4 nm, and the average particle size was 60 nm. The products obtained from various heating rates were all amorphous. By using a thermogravimetric analysis technique, a mechanism including two reaction stages was observed for the thermal decomposition of rice husk in air. The activation energy was found to be 166±10 kJ/mol. This method can conveniently provide preparation of silica of high surface area and nanometer grade.

Preparation and characterization of nano-structured silica from rice husk

Rice husk ash as an alternate source for active silica production

The characterization of rice husk ash, a deriving by-product of the burning of the rice husk during the rice processing is the object of this study. This by-product, for being rich in silica, can be an important raw material for the production of siliceous ceramics, such as thermal insulators and refractory. A combination of surface analysis, thermal analysis and microscopy analysis techniques was used for the characterization. The characterized by-product presented as main component the silica, under amorphous form, with a maximum content of alkalis around 1%, features that become it potentially interesting for the production of ceramic materials.

/pdf/caracterizacao-de-cinza-de-casca-de-arroz-para-uso-como-ou9wrd0k7f.pdf

Caracterização de cinza de casca de arroz para uso como matéria-prima na fabricação de refratários de sílica

A comparison between silica by acid leaching of rice husk (RH) and silica obtained from thermal treatment of rice husk ash (RHA) is presented. The best leaching results were obtained using 10% hydrochloric acid followed by washing with water. The alternative method, calcination of RHA at 700 oC for 6 h followed by grinding for 80 min, was more effective. Silica obtained from RH was about 97% amorphous, had a 17.37 µm mean particle size, and a specific surface area of 296 m2/g. On the other hand, for silica obtained from RHA the values were about 95% amorphous material 0.68 µm, and 81 m2/g.

https://www.scielo.br/pdf/qn/v29n6/04.pdf

Viviana Possamai Della

Papers

Rice husk ash as an alternate source for active silica production

Caracterização de cinza de casca de arroz para uso como matéria-prima na fabricação de refratários de sílica

Estudo comparativo entre sílica obtida por lixívia ácida da casca de arroz e sílica obtida por tratamento térmico da cinza de casca de arroz

Reciclagem dos residuos agro-industriais: cinza de casca de arroz como fonte alternativade silica

Reaproveitamento de residuos solidos industriais: Processamento e aplicacoes no setor ceramico