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Separation techniques can be applied to sample clean up and preconcentration processes which are key steps in analytical methods to improve the characteristic performance for the separation and detection of various analytes. Selection of the right sorbent with higher selectivity is the main objective of analysis proposed by Molecularly Imprinted Polymers (MIPs). MIPs is a separation technique are prepared by reaction sequences containing a template, one or two functional monomers, one/two crosslinking monomers, polymerization initiator in a solvent containing solution. Various studies on MIPs have been carried out because MIPs have many advantages over other methods, especially as a selective adsorbent for sample preconcentration. The aim of this study is to comprehensively and systematically examine and present bibliometric data analysis using VOSViewer using Scopus article data. it is possible to infer that VOSviewer may be used as a tool for bibliometric data analysis, whereas Publish or Perish can be utilized as a reference management tool for collecting research article data on "molecularly imprinted polymers." The data utilized in this study to analyze data with VOSviewer is research on "molecularly imprinted polymers" from the Scopus database. The total number of publications acquired relevant to the issue was 200 documents spanning the years 2018-2023. Between 2018 and 2023, the amount of research on molecularly imprinted polymers published in Scopus-indexed journals declined. The network visualization depicts the evolution map of molecularly imprinted polymers, which is separated into four clusters. Cluster 1 contains 128 topics, Cluster 2 contains 95 topics, Cluster 3 contains 90 topics, and Cluster 4 contains 73 items. So, the total number of terms in this study is 386 from four clusters.

Industrial developments have provided both positive and negative impacts for the environment. The environmental pollution caused by industrial activities discharge toxic waste such as chloride and nitrate. Therefore, recent research employed pineapple leaves (Ananas comossus) as a cellulose-based material to remove chloride and nitrate ion in aqueous solution. The pineapple leaf powder was modified using citric acid to enhance its performance. The optimum conditions were achieved at pH 2, contact time 90 minutes, concentration 100 mg/L for chloride removal meanwhile the removal of nitrate reached the peak at pH 3, contact time 150 minutes, and concentration 50 mg/L for pineapple leaves before modification. After citric acid modification, the optimum point was reached at pH 5, contact time 120 minutes, concentration 100 ppm for chloride. For nitrate adsorption, the optimums condition was at pH 4, contact time 150 minutes, and concentration 50 mg/L. The adsorption capacity of both adsorbents did not significantly change after three times adsorption/desorption cycles. Adsorption of pineapple leaf before and after modification followed the Langmuir isotherm model for chloride and nitrate removal. The obtained adsorbents were characterized using Fourier Transform Infra-Red (FTIR), Scanning Electron Microscopy (SEM) and Breuneur-Emmet-Teller (BET) indicating significant difference before and after adsorption onto pineapple leaves took place.

Industrial processes are the main source of Pb(II) contamination of natural water bodies. Pb(II) is a non-biodegradable heavy metal and carcinogen. The recent study explored the ability of citric acid-modified-kepok banana peel (CA-BP) to remove Pb(II) from an aqueous solution using the batch method. The adsorption capacity of kepok banana peel (BP) was also investigated for comparison. The optimum conditions for Pb(II) removal using kepok banana peel were achieved at pH 5, initial concentration of 600 mg l-1, contact time of 75 min, and agitation speed of 100 rpm, with an adsorption capacity of 36.478 mg g-1. Meanwhile, the adsorption capacity of citric acid modified-kepok banana peel was 64.088 mg g-1, which was reached at pH 5, initial concentration of 850 mg l-1, contact time of 75 min, and agitation speed of 150 rpm. The adsorption of Pb(II) onto both sorbents followed the Langmuir isotherm model and pseudo-second-order model, indicating monolayer adsorption with chemical interaction as a rate-limiting step. A Fourier Transform Infra-Red (FTIR) analysis was conducted to identify the functional groups present in the biosorbent and demonstrate a change in the wave number. The surface morphology of the biosorbent was examined using Scanning Electron Microscopy (SEM) before and after the absorption of Pb2+ metal ions. The objective of Energy Dispersive X-ray (EDX) is to quantify the elemental composition of the biosorbent derived from the surface of the kepok banana peel. An X-ray fluorescence (XRF) analysis was conducted to determine the chemical composition of the surface of the kepok banana peel biosorbent. Thermogravimetric Analysis (TGA) was conducted to observe the decrease in mass of the biosorbent as the temperature increased. [ABSTRACT FROM AUTHOR]

This research investigated the adsorption of Cr(VI) using HNO3 0,01 M-activated rice straw in a batch system. Some parameters such as pH, initial Cr(VI) concentration, and contact times were examined. The optimum conditions were achieved at the pH 3, initial Cr(VI) concentration 800 mg/L in 15 min with adsorption capacity 60.204 mg/g. It was found that the adsorption of Cr(VI) onto activated rice straw was followed the Freundlich isotherm model (R² = 0.9957) and pseudo-second-order model (R2 = 0.9995) indicating that adsorption chemically occurred and multilayer. Whereas the thermodynamic study revealed that Cr(VI) adsorption onto activated rice straw was exothermic (ΔH° = -8.658 kJ/mol) non-spontaneous reaction (ΔG° = positive) with liquid/solid interface disorder (ΔS° = -65,297 J/mol). The physicochemical characterization of the bioadsorbent showed a wavenumber shifting of some functional groups. The percentage of Cr(VI) in bioadsorbent increased and the surface morphology of the bioadsorbent was smoother after adsorption occurred. Thus, this locally abundant rice straw could be used as a bioadsorbent for Cr(VI) removal. [ABSTRACT FROM AUTHOR]

This paper investigated the ability of sago bark (Metroxylon sagu) as a new potential biosorbent in removing Cr(VI) in batch system. The optimum adsorption capacity of sago bark (Metroxylon sagu) was 61.73 mg/g achieved at pH 3, agitation rate of 100 rpm, contact time 60 min, particle size =32 µm, and initial concentration of Cr(VI) 1,000 mg/L at room temperature (25°C). The adsorbent regeneration was carried out using 0.01 M HNO3 with regeneration efficiency of 78.35%. The adsorption data fitted better to Freundlich and Langmuir equilibrium isotherm models. The data confirmed that Cr(VI) sorption onto sago bark (Metroxylon sagu) has good agreement with pseudo-second-order model. The thermodynamic study indicated that Cr(VI) sorption onto sago bark (Metroxylon sagu) occurred as exothermic in nature (△H = -72.55 kJ/mol), which was required energy for adsorption process, and the disorderliness decreased as temperature increased (△S = -263.06 J/mol). Thus, it can be concluded that sago bark (Metroxylon sagu) can be utilized as a potential adsorbent in Cr(VI) removal. [ABSTRACT FROM AUTHOR]