Study on removal of colour from paper industry wastewater using Biochar derived from zero liquid discharge sludge

Abstract

i newlineAbstract newlinePoor wastewater management has contaminated our water resources, motivating newlineresearchers to constantly innovate and improve existing wastewater treatment newlinetechnologies. Various techniques have been studied for their applicability to newlinewastewater treatment. The adsorption using zero liquid discharge sludge-based newlinebiochar exhibit a promising future in the field of wastewater treatment. The current newlinestudy investigates the possibility of color removal from pulp and paper mill newlinewastewater. The biochar was prepared from zero liquid discharge sludge using the newlinepyrolysis technique. It was found that the ZLD sludge-based biochar has shown much newlinebetter performance for color removal from paper mill wastewater in comparison to newlineother biochar. The current work proposes the use of ZLD sludge-based biochar for newlineremoving color from paper mill wastewater. newlineIn preparing biochar, temperature and time significantly impacted the biochar yield, newlinesurface area, and pore volume showing strong linear, quadratic, and interaction newlineeffects. By using response surface methodology (RSM), the ideal pyrolysis newlinetemperature and time were found to be 539.65°C and 176.67 minutes, respectively, newlinewith a desirability value of 0.651. The optimized values of biochar yield, surface area, newlineand pore volume were found to be 63.95%, 40.23 m2/g, and 0.048 cm3/g respectively. newlineThe use of this biochar as an adsorbent in wastewater treatment was proven by newlinephysicochemical (proximate and CHNS) and instrumental (XRD, TGA, DSC, FTIR, newlineand SEM) analyses, as well as by their comparison with other biochar published in newlinethe literature. newlineFurther, the response surface methodology approach (RSM) based Box-Behnken newlineDesign (BBD) is applied to the developed mathematical model and optimizes the newlineprocess parameters for color removal. The optimal conditions for color removal are newlinecontact time of 60 minutes, char dose of 0.6 g/100 ml effluent, and temperature 30oC newlinewhich reduced color by 70%. In addition, ANN modeling using the quotFeed-forward newlineback propagationquot network type, the quotTRAINLMquot training