RESUMO
The previous research showed that slow sand filtration (SSF) can remove the total coli by approximately 99% because of the schmutzecke layer in the filter. The presented study aimed to complete the previous research on SSF, especially on the schmuztdecke layer mechanism, to remove total coli. Total coli is a parameter of water quality standard in Indonesia, and the behavior of schmutzdecke affects the total coli removal. In the present study, the raw water from Amprong River was treated using horizontal roughing filter (HRF) and SSF. The variations in SSF rate used were 0.2 and 0.4 m/h. Total coliforms were analyzed using the most probable number test, and schmutzdecke visualization was conducted through scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX). The best coliform concentration in water treated by the combination of HRF and SSF was 4,386 colonies per 100 mL of sample using the filtration rate of 0.2 m/h, and its removal efficiency was 99.60%. However, the quality of water treated by the combination of HRF and SSF did not meet the drinking water quality standard because the removal of total coli must be 100%. The SEM-EDX visualization results in schmutzdecke showed that the average bacteria in the schmutzdecke layer were small, white, opaque, and circular, with entire edge and flat elevation. The Gram test results showed that the schmutzdecke bacteria consisted of Gram-positive and Gram-negative bacteria with basil as the common cell form.
RESUMO
The usage of wastes of bagasse would be admirable from environmental and solid waste management point of view. Thus, herein, this data set present a facile method for providing an adsorbent from mixture of bagasse-bentonite. The prepared adsorbent was applied to remove Pb2+ from aqueous solution. It was conducted in laboratory scale using completely randomized design with variations in mixed mass ratio (1:0, 1:1, 1:2, 1:3, 2:1, 3:1), pH (2, 3, 4, 5, 6, 7) and contact time (5, 10, 30, 45, 90, 120, 180 min) and the adsorption technique was batch technique. The mixed adsorbent with 3:1 of mass ratio provided the highest Pb2+ adsorption efficiency of 97.31%. The optimum pH of Pb2+ adsorption was 5 and contact time was efficient at 45 min giving adsorption efficiency of 94.76% and 93.38%. The characterization data of the adsorbent were analyzed using XRF and FTIR methods. The XRF test results showed the changes of elemental content in adsorbent after the adsorption indicated that adsorbent can absorb Pb2+. The FTIR test results showed that adsorbent has a functional group that is useful in adsorption process. Adsorption of Pb2+ by adsorbent from mixture of bagasse-bentonite follows pseudo second order model with correlation coefficient value of 99.99% (R2 = 0.9999) and Freundlich isotherm model with correlation coefficient value of 90.05% (R2 = 0.9005). The acquired data indicated that the adsorption of Pb2+ by the adsorbent prepared from mixture of bagasse-bentonite is a promising technique for treating Pb-bearing wastewaters.
