PEMANFAATAN LIMBAH AMPAS TAHU TERAKTIVASI H3PO4 SEBAGAI ADSORBEN ZAT WARNA METHYLENE BLUE

ABSTRACT
Methylene blue is an example of a frequently used synthetic dye. found in liquid waste, generally originating from the textile industry. Environmental impacts caused by synthetic dyes such as high BOD and COD, mutagenic, carcinogenic, and toxicity, degradation of dyes, especially reactive dyes, is difficult, because of their complex structure, water solubility, and synthetic nature. Therefore, it is necessary to look for effective alternatives to decompose this waste. One way to decompose liquid dye waste is by the adsorption method using tofu dregs adsorbent. Tofu dregs are waste from making tofu which can be used as an adsorbent. Tofu dregs are quite effective in adsorbing waste, but the contact time required is quite high. One way that can be done to overcome this is by making tofu dregs into activated carbon. This research aims to see whether H3PO4 activated tofu dregs waste can be used as an adsorbent for methylene blue dye, and to find out what concentration of activator provides the highest or best adsorption percentage. This research includes 6 stages, namely adsorbent preparation, carbonization, activation, characterization, adsorption and analysis using UV-VIS spectrophotometry. The activation process uses H3PO4 activator concentrations of 4 M, 6M, 8M and 10 M. The results obtained from this research are the adsorption efficiency obtained from each activator concentration, namely 4 M, was an average of 93.38%, 6 M was 94.92%, 8 M was 95.75% and 10 M was 94.76. The adsorption capacity obtained was 0.427 mg/g at 4 M, 0.434 mg/g at 6 M, 0.438 mg/g at 8 M, and 0.433 mg/g at 10 M. The results of this study showed that the best absorption was obtained by tofu dregs activated carbon with H3PO4 concentration 8 M.

Keywords : tofu dregs, adsorption, methylene blue, activated carbon, H3PO4