No abstract

No 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.

Abstract:The paper presents the results achieved during the process of nickel removal from aqueous solutions by adsorption on alumina (Aluminum oxide) in continuous conditions. The continuing experiments were conducted in a glass column with diameter of 16 mm and fi xed bed of adsorbent with quantity ranging from 30 to 115 g, adsorbent grains size from 1.0 to 2.0 mm, and retention time of 0.5 to 12 minutes. The quantity of nickel in the aqueous solutions was changed within the range of 0.045 up to 0.12 mg/l Ni. The analysis of the obtained experimental data defi ned the mutual affection of the retention time, the initial nickel concentration in the water, and the adsorbent quantity, i.e. the content of the adsorbent in the treated solution to the adsorbent capacity.According to the achieved results, logarithmic mathematical model showed best correlation between experimental and calculated values, also maximum nickel ions adsorption uptake onto the alumina were determined as 400 mg/g.

No abstract