Decolorized with activated charcoal for citric acid are two major categories: powdered activated carbon and granular activated carbon. For citric acid fermentation broth can also be processed using granular activated carbon. Granular activated carbon compared to powdered activated carbon, has the continuity, cycle characteristics, increase work efficiency, while reducing environmental pollution. Currently, citric acid bleaching performance of granular activated carbon adsorption has been used is carbon adsorption index 维尼隆 carrier, that depends on how much acid adsorption properties of activated carbon adsorption to define good and bad food decolorizing charcoal, this indicator can be partially explained charcoal adsorption properties, but applied to the citric DECOLOURIZATION not accurate. Citric acid is used as the granular activated carbon adsorption process is to be adsorbed dye solution, or even some of the other macromolecules adsorbed substances, and the molecular diameter acetate only 0.51nm, and Pigment macromolecules diameter far Therefore, activated carbon adsorption pore size range acetate represented not represent its adsorption properties of macromolecular pigment. Currently, commonly used bleaching adsorption adsorption performance indicators at home and abroad caramel (or molasses value) and methylene blue adsorption properties of activated carbon can be expressed in a large hole and the hole, but due to the current domestic citric acid used in granular activated carbon adsorption and Other decoloration granular activated carbon to the hole most of the activated carbon-based, small number of large holes, little caramel value pharmaceutical activated carbon, so the use of methylene blue adsorption Asia to illustrate the granular activated carbon adsorption of citric acid bleaching ability is more accurate a. Studies have shown that treatment of activated carbon attached to the surface of microbes resistant to toxic contaminants, making increasing metabolism. RICE and ROBSON raised by biological activated carbon source water or sewage water treatment system activated carbon, granular activated carbon in the system increases the aerobic microbial activity. EHRADT and REHA (1985) study describes the use of granular activated carbon from coal while suspended and fixing two microbial degradation of phenol system. However, the concentration of suspended microorganisms can not tolerate more than 1.5g / L of phenol, and sessile microorganisms able to survive up to 16g / L of phenol and 90% phenol adsorbed get degraded. When BETTMANN et al. (1984) speculated that the presence of the biofilm, the rate of increase is due to the degradation of phenol in such reduced microbial environment of toxic substances. Research also shows that, by activated carbon as a carrier to ease the heavy metals on the inhibition of microbial biofilms can continue to increase. FRIDEA et al (1997) study showed that when using wood charcoal degradation of phenol, powdered activated carbon was inhibited breathing creatures. WALKERA in the study, such as activated carbon treatment of dyeing wastewater, found that the use of wood powdered activated carbon treatment TB4R superior ratio is 20%, because the activated carbon adsorption increases the bioavailability and biological adsorption rate. GENT, Belgium university research with coconut shell activated carbon treatment of pharmaceutical wastewater, wastewater nitrification bacteria found harmful trace contaminants will be removed to ease microbial inhibition by toxic substances, so difficult to be biodegradable nitrogen compounds are decomposed (MISEREZ, 1999). Air purification activated carbon, coal activated carbon filter Song Xin (certified), provided by Seoul charcoal filter Gongyi City Song Xin Industrial Limited. Gongyi City Song Xin Industrial Co. filter (www.sxlc.com) is Zhengzhou, cleaning, cleaning equipment leader, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs . Song Xin filter in leadership with the staff warmly welcome all inquiries negotiations to create Song Xin filter a better future.