Simultaneous removal of nitrate and phosphate from wastewater using solid waste from factory

Abstract

Phosphorous and nitrogen concentration, respectively, between 20-100 and 500-1000 μg/L can cause eutrophication. Thus, developing efficient low-cost removal method is important to protect the aquatic environment. The aim of this study is to investigate simultaneous nitrate and phosphate adsorption capacity of solid waste residue (SWR) generated from Awash Melkassa Aluminium Sulphate and Sulphuric Acid Factory. Batch adsorption experiments were conducted to evaluate the effect of various parameters on the simultaneous removal of nitrate and phosphate ions. The experimental results show that the equilibrium time was attained within 90 min, while the optimum pH and adsorbent dose were found to be 7 and 20 g/L, respectively. The pseudo-second-order equation with R 2 values 0.99 and 1, respectively, fits to the adsorption kinetics of nitrate and phosphate. Moreover, isotherm analysis shows that adsorption of nitrate and phosphate was better modeled with Freundlich and Langmuir isotherms with R 2 0.99 and 0.98 for phosphate and 0.99 and 0.96 for nitrate, respectively. Results of regeneration of the spent adsorbent show nearly 50% of the adsorbed phosphate can be desorbed with NaOH, while that of nitrate is 99.75%. Under optimum conditions, SWR can potentially remove phosphate from wastewater. However, the adsorbent is not suitable to remove nitrate ion from wastewater.

Magnetic Mg-Fe/LDH Intercalated Activated Carbon Composites for Nitrate and Phosphate Removal from Wastewater: Insight into Behavior and Mechanisms

“…It is also important to mention that the removal efficiency of both nitrate and phosphate by the SBAC 100 MgFe composite considerably decreases in the presence of a high concentration of Cl − ions. The obtained outcomes herein are quite similar to previous works that targeted nitrate and phosphate removal by AC-based LDHs in coexistence with Cl − , CO 3 2− , and SO 4 2− ions [ 46 , 47 ].…”

Physicochemical Assessment of Borehole Water in a Reclaimed Section of Nekede Mechanic Village, Imo State, Nigeria

“…Exposure to high cadmium levels can result to kidney dysfunction and osteoporosis in humans [42]. Discharge of chemicals containing phosphate species into the soil and subsequent leaching into ground water can cause damage to the environment and deteriorate water quality [23]. The Phosphate levels in the borehole water samples ranged between 0.14 and 0.34 mg/L which is higher than the 0.03 mg/L set by the WHO.…”

“…The activities by the artisans in these sites have greatly polluted the soil and groundwater within and around their environs [8]. Many environmentally unfriendly chemical species like petroleum hydrocarbons [9][10][11][12][13][14][15], polychlorinated biphenyls [16], polybrominated diphenyl ethers [17], polycyclic aromatic hydrocarbons [18][19][20], anions [21][22][23] and heavy metals [24][25][26][27][28][29] from automobile repair and maintenance activities have been found in the air, soil and portable water sources in these areas.…”

Assessment of fish scale biosorbent in the treatment of seafood processing plant wastewater

“…Langumir model with linear plotted 1/ q e versus 1/ C e is shown in the following equation: where q e is the equilibrium adsorbate concentration (mg g −1 ) in solution, q m is the maximum adsorption capacity (mg g −1 ) and K L is the Langmuir constant (L mg –1 ). Moreover, a dimensionless constant, commonly known as separation factor ( R L ) is presented in Eqn (5) 16 : where K L (L mg –1 ) refers to the Langmuir constant and C 0 is the adsorbate initial concentration (mg L −1 ). The computed R L value suggests the adsorption nature to be either unfavorable ( R L > 1), linear ( R L = 1), favorable (0 < R L < 1) or irreversible ( R L = 0) 16 …”

“…Moreover, a dimensionless constant, commonly known as separation factor ( R L ) is presented in Eqn (5) 16 : where K L (L mg –1 ) refers to the Langmuir constant and C 0 is the adsorbate initial concentration (mg L −1 ). The computed R L value suggests the adsorption nature to be either unfavorable ( R L > 1), linear ( R L = 1), favorable (0 < R L < 1) or irreversible ( R L = 0) 16 …”