Arniza Ghazali

Removal of Pesticides from Water and Wastewater by Different Adsorbents: A Review

In this review article, the use of various low-cost adsorbents for the removal of pesticides from water and wastewater has been reviewed. Pesticides may appear as pollutants in water sources, having undesirable impacts to human health because of their toxicity, carcinogenicity, and mutagenicity or causing aesthetic problems such as taste and odors. These pesticides pollute the water stream and it can be removed very effectively using different low-cost adsorbents. It is evident from a literature survey of about 191 recently published papers that low-cost adsorbents have demonstrated outstanding removal capabilities for pesticides.

The use of date palm as a potential adsorbent for wastewater treatment: a review

BackgroundIn tropical countries, the palm tree is one of the most abundant and important trees. Date palm is a principal fruit grown in many regions of the world. It is abundant, locally available and effective material that could be used as an adsorbent for the removal of different pollutants from aqueous solution.ReviewThis article presents a review on the role of date palm as adsorbents in the removal of unwanted materials such as acid and basic dyes, heavy metals, and phenolic compounds. Many studies on adsorption properties of various low cost adsorbent, such as agricultural waste and activated carbons based on agricultural waste have been reported in recent years.ConclusionStudies have shown that date palm-based adsorbents are the most promising adsorbents for removing unwanted materials. No previous review is available where researchers can get an overview of the adsorption capacities of date palm-based adsorbent used for the adsorption of different pollutants. This review provides the recent literature demonstrating the usefulness of date palm biomass-based adsorbents in the adsorption of various pollutants.

Oil Palm Biomass–Based Adsorbents for the Removal of Water Pollutants—A Review

This article presents a review on the role of oil palm biomass (trunks, fronds, leaves, empty fruit bunches, shells, etc.) as adsorbents in the removal of water pollutants such as acid and basic dyes, heavy metals, phenolic compounds, various gaseous pollutants, and so on. Numerous studies on adsorption properties of various low-cost adsorbents, such as agricultural wastes and its based activated carbons, have been reported in recent years. Studies have shown that oil palm–based adsorbent, among the low-cost adsorbents mentioned, is the most promising adsorbent for removing water pollutants. Further, these bioadsorbents can be chemically modified for better efficiency and can undergo multiple reuses to enhance their applicability at an industrial scale. It is evident from a literature survey of more than 100 recent papers that low-cost adsorbents have demonstrated outstanding removal capabilities for various pollutants. The conclusion is been drawn from the reviewed literature, and suggestions for future research are proposed.

Oil Palm Biomass as a Precursor of Activated Carbons: A Review

Commercial activated carbon has been a preferred adsorbent for the removal of various pollutants, and its widespread use is restricted due to its relatively high costs, which led to the researches on the possible alternative nonconventional and low-cost adsorbents. The use of agricultural products and by-products for instance has been widely investigated as a replacement for the current costly methods of removing various pollutants. In this critical review, an extensive list of the production of activated carbon from oil palm biomass is presented. The effects of various process parameters on the pyrolysis stage, characteristics, and influences of physical and chemical activating conditions on the production of activated carbons from oil palm biomass are discussed. A comparison in characteristics and applications of activated carbons from oil palm biomass with commercial activated carbons is made. It is evident from a literature survey of about 200 recently published articles that activated carbons from oil palm biomass exhibit outstanding capabilities for removal of various pollutants.

Characterization and adsorption kinetic study of surfactant treated oil palm (Elaeis guineensis) empty fruit bunches

AbstractOil palm (Elaeis guineensis) empty fruit bunches (OPEFB) was treated with cetyltrimethylammonium bromide (CTAB) to make its surface suitable for methyl orange (MO) dye adsorption. CTAB-treated OPEFB samples were characterized for their surface functional groups using FTIR, pHzpc, proton-binding capacity, and Boehm titration techniques. The surface morphology and elemental composition of the sample were also studied, employing field emission scanning electron microscopy and energy dispersive X-ray spectroscopy (EDS). It was found that in totality, acidic surface functional group increased after CTAB treatment. The adsorption process was well explained with pseudo-second-order kinetic model. The obtained equilibrium sorption data were then analyzed using the Langmuir, Freundlich, Dubinin–Radushkevich, and Tempkin isotherms. The results showed that sorption was surfactant dose dependent and adsorption increased with an increase in the percentage of surfactant applied on the OPEFB. The maximum adsorpt...

Energetics of anionic surfactant-additive systems at the cloud point

The energetics of clouding in anionic surfactant (SDBS) and tetrabutylammonium bromide system in the presence of additives, such as ureas, amino acids and sugars is reported. The change of standard Gibbs energy of solubilization (ΔGso) for all of the additives was found to be negative. The values of change of standard enthalpy (ΔHso) and that of standard entropy (TΔSso) values were found to depend on the type and chemistry of the additive. The results were explained on the basis including chemistry of additives, their effect on water structure, and solubilization of additives either in the micellar or in aqueous phases.

Optimization of the Strength Properties of Waste Oil Palm (Elaeis Guineensis) Fronds Fiber

ABSTRACT In this study, Box-Behnken design (BBD) and response surface methodology (RSM) was applied to study the effects of alkaline peroxide treatment variables (cooking time, sodium hydroxide concentrations, and hydrogen peroxide concentrations) on the pulp and paper strength properties (screened pulp yield, kappa number, tensile index, tear index, burst index), which are considered dependent variables or response variable of the extracted cellulose from oil palm (Elaeisguineensis) fronds (OPF) vascular bundle fibers. The results indicated that at the optimum operating conditions of 2.35% NaOH, 5.00% H2O2 and a 53.41 min cooking time, resulting maximum strength properties (tensile index, burst index, tear index,) gave 9.92 Nm/g, 6.55 KPam2/g, 6.22 mNm2/g, respectively. The study revealed that alkaline peroxide pulped fibers of oil palm frond vascular bundles could be considered a suitable alternative for paper qualities with moderate strength requirements.

Alkaline Peroxide in Synergy with Mechanical Refining as Factor in the Development of EFB Paper Properties

Pulp from the oil palm empty fruit bunches (EFB) was extracted via Alkaline Peroxide Pulping (APP). The pulping process was conducted through three main steps; dewaxing of EFB, impregnation of alkaline peroxide (AP) into EFB and refining of biomass to finally produce the pulp. The varying peroxide levels and number of impregnation stages were found to affect the refining energy consumption and the properties of the resultant pulp and paper. Diagnosis by electron microscopic imaging revealed a strong correlation between paper properties development and paper surface morphologies. By multiplying the stages of the low alkaline peroxide level (2:2.5% AP) impregnation, refining energy could be reduced by 30% while improving brightness and paper mechanical properties. Higher alkaline peroxide level (4:5% AP) could reduce the refining energy by 50% while still improving brightness. Beyond these AP levels (8:10% AP), refining energy could be reduced by 67% by increasing the number of impregnation stages, with positive effects on brightness and paper mechanical properties. The findings suggest that increasing the AP impregnation stages had exposed more active sites to react with AP. The enhanced AP accessibility to EFB structures facilitated mechanical fibrillation of EFB vascular bundles through the refining process. The proper synergy between AP and the adopted mechanical refining was the factor that triggered the liberation of nanocells from EFB biomass and this had ultimately improved paper properties.

Alkaline peroxide pulping of oil palm empty fruit bunch by variation of chemical strength

Papers produced from oil palm empty fruit bunches (EFB) via Alkaline Peroxide Pulping (APP) was preceded by three main steps; dewaxing of EFB, alkaline peroxide (AP) impregnation into EFB and refining of biomass to generate pulp. The experiment was carried by varying chemical level and number of impregnation stages. For 2:2.5% AP level, two-stage impregnation improved hand sheets tear index by 45%, 164% boost in tensile index, 26% enhancement in zero span index and more than 5% in burst index. By applying 8:10% AP level, significant improvements were gained at the third and fourth stages of AP impregnation. Although there was no significant change in hand sheet strength with multiple impregnation for 4:5% AP level, improvement in brightness of hand sheets was apparent, analogous to the effect of increasing AP level. The found paper properties development show that alkaline peroxide pulping of EFB could be adapted to various targeted properties by adjustment of AP level and impregnation stages.

Scaffolding Social Support Amongst the Fresher Students Through Mapping Activities

Mapping activities (coded as PIT2 and PIT3) as means of transferring learning autonomy to students were implemented and evaluated to understand the way learning of the fresher students in the second semester of their first year in the Bachelor of Technology in BPC (Bioresource, Paper and Coatings) programme was affected. The observed initial tendency of clicking only with classmates of the same ethinicity was severe and the group of learners is thus, hereby addressed as ‘stiff community’. To rectify the situation, the performed PIT3 mapping activities allocating an equal opportunity for students to participate by filling up numbered blank ovals, witnessed intensive interaction across the ethnic groups. Instructor’s deliberation suggests the effectiveness of PIT3 as an indirect instruction to rapport and improvement in the social support. The findings, which are in 100% agreement with students’ self report (SSR), moreover demonstrate the function of mapping activities in reinforcing students’ cognitive engagement through selection of keywords representing the principal idea that learners use in their own exploration of the learning materials. Besides acting as points triggering curiosity, keywords allow transfer of greater learning autonomy to students. The un-stiffening phenomenon from PIT3, which better prepared students for PIT2—verbal description of co-constructed map, in turn, supports learning via good relationship, teamwork and sustainability of performance throughout the academic year. Moving from the desirable scaffold social impact, the applied modes of mapping activity are potentially the seed initiative to inculcate the attributes for global citizenship in any other learning setting.