PEMANFAATAN KATALIS BEKAS (BERBASIS Fe) SEBAGAI BAHAN PENGISI PAVING BLOCK

Abstract

Used-catalyst with Fe basis, which used inside the ammonia reactor (converter) in ammonia Plant, has became a complicated problem in its recycling or re-using, besides of its big amount, ex-catalyst waste also has no-economic value to be re-used. One of the alternatives solution in re-cycling/re-using the above waste that is by solidification or stabilization, by changing the physical characteristic and chemical of this waste with tying- compound (cement) to become a monolith and strong compound, so it's expected that the movement of catalyst compound can be blocked and limited. To observe more solidification effects to Fe compound in the used-catalyst, which has released or leached from monolith structure, the research sampling of used-catalyst tying to become a strong structure has been elected, that is Paving Block. The research method used is Case Study in the Ammonia Plant of PT. KPA Bontang, where on November 2003, unloading activity performed for used-catalyst in Ammonia converter 2"d stage. The above used catalyst, along with sand as the "aggregates" mixed with cement, then pressed to be a paving block and has been tested by TCLP (Toxicity Concentration Leaching Procedure) to find-out the leaching Fe possibility of the paving block and strength test to ensure that the strength are not lower than paving block sold in the market. For TCLP test, research variable choose is soaking duration and the composition of used-catalyst waste added t o the paving b lock processing. Whilst for strength test, choose lifetime and the composition of used-catalyst waste added to the paving, as the variable. From the research sampling obtained, with soaking duration vary, shown that Fe leached between 3, 7, 14, 21, and 28 days — all are still below than limitation standard (1 ppm, as clean water requirement). So is the effect of the used-catalyst composition, as a mixture of basic material, the fact shown that it is not much affecting Fe leached. This shown that tying of cement to aggregate material (read• catalyst & cement) can be stated perfect and accepted by environment. Whilst the strength test pressing, from the research result found that lifetime of paving block will causing the trend increasing of strength test significantly enough. Moreover the effect of ex-catalyst added, generally will increase the strength, but within a maximum limitation, where from the trial result - obtained strength test with optimum condition is on the following compare composition: Cement : Sand : Used-catalyst = 0.25 : 1.00 : 1.50 As a whole, strength test of this used-catalyst paving block is bigger than common paving block, from the trial-result at day 215t of used-catalyst paving, for common paving — average result is 89.2 Kg/cm2, whilst for used-catalyst paving on the sample composition I (the lowest used-catalyst content) is 132.07 kg/cm2. Key word: Solidification, Aggregates, Leached Fe Content Analysis, and Compressive Strength Test.