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The present study is concerned with the methods and means to safely produce relatively small amounts (i.e., up to 50 kg/h) of ammonia. The equilibrium and kinetic study of urea hydrolysis was conducted in a semibatch reactor at atmospheric pressure to investigate the effects of reaction temperature, initial feed concentration, and time on ammonia production. This study reveals that conversion increases exponentially with increasing temperature but decreases slightly with increasing initial feed concentration of urea. Furthermore, the effect of time on conversion was also studied; it was found that conversion increases with increasing time. Using collision theory, the temperature dependency of the forward rate constant was determined, from which the activation energy of the reaction and the frequency factor were calculated. The activation energy and frequency factor of the urea hydrolysis reaction at atmospheric pressure were found to be 60.93 kJ/mol and 4.259 × 105 min−1, respectively.

A technical and feasibility assessment has been conducted for catalytic cracking of waste plastics to produce fuel oils in Malaysia. The availability and current technologies for using plastic waste has been reviewed. Flow sheet for the process has been conceptualized and the material and energy balances for the process along with a plant‐wide simulation using the software ASPEN Plus have been undertaken. Amorphous silica‐alumina has been proposed as catalyst to give 94.36% conversion. Furthermore, the economic analyses for small, medium, and large scale have been done and in all cases, the rates of return (ROR) analysis have been undertaken. From the economic analysis, it has been observed that the total estimated cost for a large scale plant would be USD $58,591,260 for an annual feed rate of 120,000 ton. Based on current market of gasoline and diesel the payback period for the large scale plant would be 1.42 yr with the total annual profit of USD $72,933,156, which corresponds to a ROR of 35.97%. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 298–307, 2014

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