Utilization of Rice Husks into Biochar and Nanosilica: For Clean Energy, Soil Fertility and Green Nanotechnology

Abstract

Rice husks are often dumped and burned in the field that emits greenhouse gases. Through green nanotechnology, developing these materials into diverse applications will not only create an avenue for new ideas and innovations but also beneficial to the environment. Thus, this study aimed to utilize rice husks in an eco-friendly way. Rice husks were converted into rice husk biochar (RHB) through continuous-type rice husk pyrolizer (CtRHP) which produces two important products: heat energy and biochar. High grade RHB was used as an amendment for degraded acid upland soil (Annam series) grown with corn. Plant height and biomass, and total N uptake, increased linearly with increasing rates of RHB levels. A linear trend of the effects of RHB on soil pH (water), and total N with the increasing RHB rates while soil pH and OC had a quadratic trend. The produced RHB were further derivatized into nanosilica (nSi). Characterization of nSi through SEM micrographs showed a cloudy-like structure with various particle sizes ranging from 5 to 20 nm, while XRD analysis revealed that the synthesized nSi is amorphous. Converting RHB into nSi will have various industrial applications such as catalysts, electronic and thin film substrates, and humidity sensors.

Cultivating Tomorrow: A Comprehensive Review of Agricultural Innovations in the Philippines (2018-2023)

“…Additionally, alternate wetting and drying (AWD) technology for rice cultivation improves soil properties and plant growth compared to continuous ooding [20]. Agricultural waste products, such as rice husk biochar, enhance soil nutrients and plant biomass in degraded upland soil [23]. Vertical hydroponic farming of onions using rice husk substrates results in signi cantly higher bulb growth compared to eld cultivation [27].…”

“…Vertical hydroponic farming of onions using rice husk substrates results in signi cantly higher bulb growth compared to eld cultivation [27]. Innovations like nanosilica and mushroom compost derived from rice husks offer additional income streams for farmers [23,20], showcasing the versatile use of agricultural waste products for sustainable practices and income generation. Moreover, studies emphasize technology's role in sustainable agriculture through precision monitoring and control of growing environments [26,24] and optimizing productivity and costs [25].…”

Transforming Philippine Agriculture Through Data-driven Innovation: A Quantitative Landscape Assessment to Prioritize Technological Solutions

“…The studies also demonstrate the potential of agricultural waste products. Rice husk biochar increases soil nutrients and plant biomass in degraded upland soil (Sarong et al, 2020). Vertical hydroponic farming of onions using rice husk substrates resulted in signi cantly higher bulb growth compared to eld cultivation (Pascual et al, 2018).…”

Valorization of Agricultural Wastes to Offset Greenhouse Gases (GHGs) Emissions: An Insight in Southeast Asia

“…Rice is a major crop grown in most countries in SEA, with Indonesia having the highest output [1,12,13] . Vietnam is the second highest rice producer, followed by Thailand, the Philippines, and Myanmar.…”