Pada masa kini, perlombongan dan industri penyaduran elektrik adalah sumber
paling ketara pencemaran air. Bahan cemar logam berat yang dilepaskan ke persekitaran
telah menyebabkan pelbagai kesan terhadap alam sekitar. Dalam kajian ini, penjerapan
Zn2+ ke penjerap (hampas tepu yang dirawat KOH, dirawat HCl dan tanpa rawatan) telah
dikaji. Semasa penyingkiran Zn2+ teknik berkala digunakan dan kesan larutan pH, jumlah
penjerap, kepekatan awal Zn2+ dan masa penjerapan diselidik. Keadaan yang optimum
untuk penyingkiran peratusan tertinggi Zn2+ pada 76% dicapai pada pH 5, 1.0 g jumlah
penjerap, masa penjerapan 90 minit dan 100 mg/L kepekatan awal Zn2+. Kapasiti
maksimum penjerapan adalah 8.80 mg/g selepas 90 minit masa penjerapan dengan
kepekatan awal Zn2+ 250 mg/L, 1.0 g dos penjerap dan optimum pH 5.0. Model Langmuir
telah didapati sebagai model terbaik untuk data keseimbangan. Penjerapan kinetik telah
mengikuti persamaan tindakbalas pseudo-kedua yang menunjukkan proses penyerapan
kimia antara hampas tebu dan Zn2+. Pencirian kajian telah dijalankan menggunakan
“Fourier Transform Infrared Spectroscopy (FTIR)”. Kumpulan berfungsi utama yang
ditemui di hampas tebu adalah rengangan C-O. Hampas tebu yang dirawat KOH sebelum
penjerapan mempunyai tinggi kumpulan berfungsi regangan C=O, regangan C=C,
lenturan C-H dan regangan O-H berbanding hampas tebu yang tidak dirawat sebelum
penjerapan. Disimpulkan bahawa hampas tebu dirawat KOH mempunyai kapasiti
penjerapan tertinggi untuk Zn2+ berbanding hampas tebu dirawat HCl dan tidak dirawat.
Hampas tebu dirawat KOH adalah penjerap yang murah dan mesra alam untuk
penyingkiran Zn2+ di dalam larutan akueus.
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Nowadays, mining and electroplating industry are the most significant source of
water pollution. Heavy metals pollutant which releases into environment, have resulted
in various environmental impacts. In this study, adsorption of Zn2+ onto the adsorbent
(KOH-treated, HCl-treated, and untreated sugarcane bagasse) was examined. During the
removal of Zn2+ process, the batch technique was used and the effect of pH of the solution,
the adsorbent dosage, initial concentration of Zn2+ and contact time were investigated.
The optimum conditions for the highest percent removal of Zn2+ of 76% were achieved
at pH 5, 1.0 g adsorbent dosage, contact time of 90 min and 100 mg/L initial concentration
of Zn2+ solution. The maximum adsorption capacity was 8.80 mg/g after 90 minutes
contact time with an initial concentration of 250 mg/L, 1.0 g adsorbent dosage and
optimum pH of 5.0. Data obtained from batch adsorption experiment fitted well with the
Langmuir isotherm model. The adsorption kinetic followed the pseudo-second-order
equation which demonstrated a chemisorption process between sugarcane bagasse and
Zn2+. The characterisation studies were performed using Fourier Transform Infrared
Spectroscopy (FTIR). The major functional groups found in the sugarcane bagasse is CO
stretch. KOH-treated sugarcane bagasse before adsorption has higher functional group
C=O stretch, C=C stretch, C-H bending and O-H stretch compare to untreated sugarcane
bagasse before adsorption. It was concluded that the KOH-treated sugarcane bagasse had
higher adsorption capacity for Zn2+ compared with the HCl-treated and untreated
sugarcane bagasse. The KOH-treated sugarcane bagasse was an inexpensive and
environmentally friendly adsorbent for Zn2+ ions removal from aqueous solutions.
Effect of pretreatment on sugarcane bagasse for removal of zinc (ii) ions from aqueous solution / Wan Mohd Haffizrul W Mohd Apandi