| With increasingly stringent environmental regulations, the vehicle fuel quality requirements more stringent all over the world, ultra-low sulfur clean fuel technology has been becoming a research hotspot. Rice hull as raw material, was chosed to prepare carbon-based adsorbents by Zncl2 activatation, which are used for adsorptive deep desulfurization of diesel fuel. Effects of Zncl2 concentration, the mass ratio of Zncl2 to the raw material, activation temperature, activation time and SiO2 removal on textural structures and DBT adsorption performance of the prepared rice hull-based carbons, were investigated. Four surface modification approaches (concentrated nitric acid oxidation, concentrated sulfuric acid oxidation, peracetic acid oxidation, low temperature thermal oxidation at 350℃) were used to treat the prepared rice husk-based carbon, which produced four rice hull-based carbons with different chemical properties, and DBT adsorption capacity of the surface modified carbons was tested. In addition, textural structures and surface chemical properties were studied by using N2 adsorption, Boehm titration and FT-IR; Finally, adsorption model of DBT on the rice hull-based carbons was studied.Experimental results showed that:when the carbonization temperature of rice hull was 400℃, carbonization time was 30min, activation temperature was 600℃, activation time was 1 h,50% wt of zinc chloride was an activator, and the weight ratio Zncl2 to carbonized rice hull was 2, the surface area and micro-pore volume and DBT adsorption capacity all reached maximum; the adsorption capacity was 31.25 mgS/g, and specific surface area and pore volume were 1342 m2/g and 0.332 cm3/g, respectively. During the adsorption process of DBT on the rice hull-based carbons, the surface chemical properties of the carbon have the most notably effect on DBT adsorption; and surface strong acidic groups play a decisive role. DBT adsorption on the rice husk-based carbon meets the Langmuir adsorption model.
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