Improved Dye Removal Ability of Modified Rice Husk with Effluent from Alkaline Scouring Based on the Circular Economy Concept

Abstract

To improve the ability of the rice husk to purify colored wastewater, effluent from the alkaline scouring of cotton yarn was used immediately after the scouring (without cooling and additionally added chemicals) in order to remove the non-cellulosic silicon-lignin shield from the rice husk’s surface. This rice husk, with 93.8 mg/g adsorption capacity, behaves similarly as the rice husk treated with an optimized alkaline scouring recipe consisting of 20 g/L NaOH, 2 mL/L Cotoblanc HTD-N and 1 mL/L Kemonecer NI at 70 °C for 30 min with an adsorption capacity of 88.9 mg/g of direct Congo red dye. Treating one form of waste (rice husk) with another (effluent from the alkaline scouring of cellulosic plant fibers), in an effort to produce a material able to purify colored effluent, is an elegant environment-friendly concept based on the circular economy strategy. This will result in a closed-loop energy-efficient process of the pre-treatment of cotton (alkaline scouring), modification of rice husk using effluent from the alkaline scouring, dyeing cotton fabrics and cleaning its colored effluents with modified rice husk without adding chemicals and energy for heating.

Perspectives on the microorganism of extreme environments and their applications

“…Bioscouring is the removal of non-cellulosic impurities (pectin and waxes) from fabric surfaces ( Dash and Sahoo, 2021 ). The conventional scouring process was tedious, degraded the quality as it required vast resources, and caused environmental pollution ( Mladenovic et al., 2020 ). Enzyme scouring enhances the wetting ability and the fabric's absorbance nature and is also environment friendly.…”

Rice Husk—Cellulose-Based Agricultural Waste Enhances the Degradation of Synthetic Dyes Using Multiple Enzyme-Producing Extremophiles

“…Previous studies have shown that rice husks, a cellulose-based agricultural waste, act as an efficient adsorbent material for dye-contaminated wastewater [ 10 , 19 ]. Based on the reported chemical composition of rice husks of 32.2% cellulose, 21.3% hemicellulose, 21.4% lignin, 1.8% extractives, 8.1% water, and 15.1% SiO 2 , rice husks are natural cellulosic fibers that have strong potential for dye adsorption and decolorization [ 20 , 21 ]. However, few studies have focused on the function of rice husks as a sustainable carbon source for microbial activity.…”

Recovering the Soybean Hulls after Peroxidase Extraction and Their Application as Adsorbent for Metal Ions and Dyes

“…Compared to conventional adsorbents (i.e., activated carbons, ionexchange resins, and inorganic materials such as alumina, silica gel, and zeolites), green waste-derived adsorbents are economically viable (their cost-potential makes them competitive) and have proven satisfactory adsorption capacities toward heavy metals and dyes. The most studied green waste-derived adsorbents are sugar beet shreds [13], fibers [14][15][16][17], rice husk [18], wood-based adsorbents [2,[19][20][21], potato peels [22,23], and other cellulose-based adsorbents [7]. Although green waste-derived materials are intensively studied as adsorbents for heavy metal ions and dyes, the exploration of new eco-friendly, biodegradable, low-cost, and abundant adsorbents that have low/no negative impact on the environment remains primary focus of investigation among researchers.…”