Adsorption Behavior of DOM by PACs with Different Particle Sizes

Abstract

Particle size of powdered activated carbon (PAC) is an important factor influencing the adsorption behavior of organic matter, but the effect of PAC particle size on the removal of different fractions of dissolved organic matter (DOM) is still not well understood. In this work, natural water from a site with anthropogenic influence was used as test water, and the adsorption behavior of different DOM fractions onto three PACs with different particle size was investigated. The results demonstrated that the DOM removal was enhanced 83.3% when the PAC particle size decreased from 76.0 to 19.1 mm. The majority of increased adsorption capacity could be ascribed to microbial by-product and humiclike fractions, or to mid-molecular weight fraction DOM. With the decrease of PAC particle size, the adsorption kinetic constant of low-molecular fraction was greatly enhanced, but the adsorption capacity was enhanced less significantly. By comparing the Brunauer-Emmett-Teller surface area and pore size distribution of PACs with different particle sizes, it was confirmed that the improvement of adsorption by reducing PAC particle size could be attributed to the increase of accessible PAC surface area and decrease of diffusion distance for DOM molecules.

Influence of the properties of 7 micro-grain activated carbons on organic micropollutants removal from wastewater effluent

“…MB numbers) ranging from 200 to 320 mg/g (Figure 1), similar to those obtained at pH = 5.0 after 160 h from commercial GACs prepared with similar raw material (Wang et al, 2005) or with different raw materials (Rafatullah et al, 2010), and from non-commercial GACs after 48 h (Raposo et al, 2009). The MB number was negatively correlated with the particle size (d50, rPearson = 0.93, p-value = 0.003), confirming that MB and by extension OMPs adsorption kinetics are controlled by particle size (Delgado et al, 2012;Raposo et al, 2009;Shi et al, 2014). The MB number was also negatively correlated with the ash content (rPearson = -0.77, p-value = 0.041).…”

Superiority of wet-milled over dry-milled superfine powdered activated carbon for adsorptive 2-methylisoborneol removal

“…Powdered activated carbon (PAC) is used widely in water treatment processes because of its ability to remove dissolved pollutants that cannot be removed by the conventional process of coagulation, sedimentation, and sand filtration (Cook et al 2001, Li et al 2003, Matsui et al 2003, Shi et al 2014.…”

Synergistic Adsorbent Sequence for Dissolved Organic Nitrogen Fractional Removal from Biotreated Pharmaceutical Wastewater

“…As a meso-microporous material, CX6.8 would be more capable of removing low-MW DON than CX6.2 according to the pore size effect and pore filling. 15,42 Interestingly, the performance of the sequential adsorption column of the three CXs was better than that of the two, indicating that CX5.4 might play a role in improving the adsorption capacity of CX6.8.…”