Efficient Rice-Husk-Derived Silica Nanocatalysts for Organic Dye Removal from Water

Violeta-Carolina Niculescu,Maria Raboaca

doi:10.3390/catal11070815

Abstract

Rice is the second most extensively consumed food ingredient, and its by-products in the paddy field include rice husk and straw. Rice husk ash, resulting from rice husk burning, is considered an environment menace, inducing negative effects on the area in which it is disposed of. In this study, rice husk was applied as a silicate source to obtain mesoporous silica material. Characterization techniques confirmed the well-ordered mesophase and resemblance of mesoporous silica resulting from rice husk ash with one obtained from conventional silica sources. The mesoporous silica material was further used as catalyst support. The resulting catalysts were used for rhodamine 110 oxidation, proving high potential for oxidizing hazardous organic compounds, such as dyes from water, resulting in environmentally harmless products.

Highlights

Nowadays, disappearance of raw resources and excess waste constitute major issues worldwide
The obtaining approach relied on the hydrothermal treatment of the porous silica resulting from the rice husk, which was the matrix and the raw material for further processing
The cost of a commercial MCM-41-type mesoporous silica can reach approximately 26,000 euro/kg. This investigation showed that rice husk is an agricultural waste by-product and can be assessed as raw material for extracting amorphous silica

Summary

Introduction

Disappearance of raw resources and excess waste constitute major issues worldwide. The commercial exploitation of industrial and agricultural wastes is increasing, which is observed mainly in agribusiness. This can be considered a potential income and an option for reducing waste production and environmental effects [2,3]. Rice (Oryza sativa), from the Gramineae family, is considered to be in second position in terms of being the most extensively eaten food ingredient. It typically contains 20–25% rice husk (RH), which is discarded as waste from the rice mill industry. China and India are the major producers, accounting for around 50 wt% of the total rice production

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Results

Conclusion