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Hydroisomerization of n-hexadecane is performed over ZSM-12 framework having tailored Brønsted acidity to investigate the effect in terms of product selectivity and yield. For this purpose, pure phase of ZSM-12 (bulk molar ratio Si/Al * 60) has been synthesized using TEABr as a structure directing agent. The framework Brønsted acidity is tailored with group II elements (M) viz. Ca, Ba and Mg, by means of ion-exchange method. The samples so prepared have been characterized for phase purity, textural parameters, morphology by employing powder X-ray diffraction, nitrogen adsorption-desorption isotherm measurement at 77 K, and scanning electron microscopy technique, respectively. Similarly, % metal exchange is estimated using inductively coupled plasma technique. The quantification of Brønsted acidity for H ? -M ?? -ZSM-12 samples has been estimated by means of ammonia temperature programmed desorption (NH 3 -TPD) and Fourier transform infrared spectroscopy of ammonia (NH 3 -FTIR). The well characterized H ? -M ?? -ZSM-12 samples were loaded with Platinum (Pt, 0.5 wt%) and subjected to hydroisomerization of n-hexadecane using an up-flow fixed bed reactor to verify the effect of process parameters like temperature and WHSV. Pt/H ? -Ba 2? -ZSM-12 with tailored Brønsted acidity in the range of about 25 % demonstrated the optimum performance among all the catalysts with an increased isomer selectivity and yield (89.2 and 80.3 %, respectively) by about 4 wt% at a conversion level of about 90 % compared to Pt/H ? -ZSM-12 framework at 568 K. Such enhancement in isomer selectivity and yield is found to be significant from commercial application point of view. Based on the obtained trend, the potential benefits of implementation of Pt/H ? -Ba 2? -ZSM-12 (bulk molar ratio Si/Al * 60) framework for cold flow property improvement of 'bio-ATF' have been envisaged.

Hydroisomerization of n-hexadecane has been investigated over ZSM-22 framework by varying bulk molar Si/Al ratio in the range from 30 to 90 at constant platinum loading of about 0.45 wt %. Thus, ZSM-22 samples have been synthesized and characterized with respect to their crystallinity, textural parameters, and total acidity by means of X-ray diffraction, nitrogen adsorption desorption isotherm measurement at 77 K, and temperature-programmed desorption of ammonia technique, respectively. The effect of hydroisomerization reaction parameters, namely, temperature and weight hourly space velocity (WHSV), on n-hexadecane isomer selectivity and yield has been investigated. The optimal results over prepared catalysts demonstrated the best possible performance over ZSM-22 framework with bulk molar Si/Al ratio of 45, wherein the C 16 product with isomer selectivity and yield (82.7 and 74.8%, respectively) and pour point of 252 K have been achieved at a conversion level of about 90% at 578 K. Based on the obtained results, the possible advantages of using ZSM-22 (bulk molar Si/Al ∼ 45) framework cold flow property improvement of long chain n-paraffins can be envisaged.

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